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Isaac is strengthening

By: Dr. Jeff Masters, 2:58 PM GMT on August 24, 2012

Tropical Storm Isaac is strengthening. An Air Force Reserve hurricane hunter aircraft measured surface winds of 60 mph on the east side of the center, about 170 miles south of Santo Domingo in the Dominican Republic, at 8:40 am EDT this morning. Winds at the aircraft's flight level of 5,000 feet were hurricane force, 76 mph. The surface pressure remained fairly high, at 1000 mb. Tropical cyclones have a warm core, and the Hurricane Hunters typically find that a storm's lowest pressure is also where the warmest temperature are. However, this morning's flight found that Isaac was still disorganized, with the storm showing almost no evidence of a warm core. Isaac's warmest temperatures were displaced 75 miles to the west of where the lowest pressure was. There were no signs of an eyewall beginning to build. Infrared and visible satellite loops show that Isaac is somewhat asymmetric, with a large band of intense thunderstorms to the east, separated from the core region. This is interfering with both the storm's low-level inflow and upper-level outflow, but the band appears to be dying out. An analysis of upper level winds from the University of Wisconsin CIMSS shows an upper-level outflow channel well-established to the north, and an intermittent outflow channel to the south.


Figure 1. Evening shot of Tropical Storm Isaac taken on August 23, 2012, by the NOAA Hurricane Hunters.

Isaac's rains
Radar imagery from Puerto Rico shows that Isaac is dumping some very heavy rains to the south and east of the center. Ponce, Puerto Rico had a wind gust of 37 mph this morning as a heavy band of rain moved through, and radar-estimated rainfall amounts are in excess of 7 inches for the region just north of Ponce. Power outages to 2,000 homes have been reported in Puerto Rico this morning. NOAA buoy 42085 offshore from Ponce reported a wind gust of 54 mph near 9 am EDT this morning. Rainfall estimates from microwave satellite instruments suggest that Isaac's heaviest rains are to the south of the center, and that the Dominican Republic and Eastern Haiti will escape the worst of Isaac's rains. Haiti's southwest peninsula and Eastern Cuba should suffer the heaviest rains.


Figure 2. Radar-estimated precipitation from the Puerto Rico radar shows the region near Ponce has received up to 7" of rain as of 10 am EDT August 24, 2012.

Latest model runs for Isaac
The latest set of 00Z and 06Z (8 pm and 2 am EDT) model runs have come into better agreement, thanks to the dropsonde mission by the NOAA jet yesterday afternoon and evening. Isaac should move over Haiti's southwest peninsula and then eastern Cuba, then track along the spine of Cuba before popping off into the Florida Straits on Sunday. A trough of low pressure will then pull Isaac to the northwest, and then north, towards the Central Gulf Coast. Landfall locations range from Mississippi (06Z HWRF model run) to the Florida Panhandle south of Tallahassee (06Z GFDL model run.) It is possible that the trough of low pressure pulling Isaac to the north may not be strong enough to pull Isaac all the way to the northeast and out to sea, and the ECMWF model indicates that Isaac could stall out after landfall over the Tennessee Valley for several days.


Figure 3. Predicted 5-day rainfall total ending at 2 am EDT Wednesday August 29, from Tropical Storm Isaac. Graphics were generated from the 6Z (2 am EDT) August 24, 2012 run of the HWRF model. Image credit: Morris Bender, NOAA/Geophysical Fluid Dynamics Laboratory.

Intensity forecast for Isaac
Isaac has not intensified as much as predicted, and I think that the storm's very large size is partially responsible for that. It's tough to spin up as much atmosphere as Isaac is attempting to do very quickly. Conditions remain favorable for intensification today, with wind shear low, 5 - 10 knots, ocean temperatures warm, 29°C, and dry air mostly mixed out of the storm's core. The large band of intense thunderstorms to the east, separated from the core region, appears to be dying out now, which will help the storm grow more organized. The storm's structure has improved considerably between 9 am - 10 am EDT, with a fairly tight center forming, exposed to view, on the north edge of Isaac's heaviest thunderstorms. A curved band of heavy thunderstorms is now trying to wrap around this center to the northeast, and this band will bring very heavy rains to Haiti and the Dominican Republic this afternoon. I expect that the Hurricane Hunters will observe a partial eyewall in their vortex reports between 2 - 4 pm EDT this afternoon. The storm's large size and disorganized structure suggests that Isaac will be able to intensify only slowly today, and will have top winds of 70 - 75 mph before encountering Southwest Haiti and Eastern Cuba tonight and Saturday. Isaac will likely be a 50 - 60 mph tropical storm on Saturday and Sunday as it moves over Cuba. Once Isaac pops off the coast of Cuba into the Florida Straits, it will be over very warm waters of 31 - 32°C (88 - 90°F), wind shear will be light to moderate. The upper-level wind pattern favorable may be quite favorable for intensification, with low wind shear due to an upper-level anticyclone over the storm--though the models disagree on whether or not this anticyclone will set up directly over Isaac or not. It will probably take at least 24 hours with the storm's center over water for it to become a hurricane. It is possible that Isaac could be approaching Category 3 strength by the time it makes landfall on Tuesday on the Gulf Coast, as suggested by the latest 06Z run of the HWRF model.

Impact on Tampa, Florida
The Republican National Convention begins on Monday in Tampa, Florida. The latest 11 am EDT wind probability forecast from NHC gives Tampa a 17% chance of receiving tropical storm-force winds and a 1% chance of receiving hurricane-force winds on Monday. Tampa is in the NHC cone of uncertainty, though near the edge of it. At a minimum, Tampa will receive very heavy rains and wind gusts in excess of 40 mph. Isaac is going to be hard-pressed to bring hurricane-force winds to the city, though, since any path that takes it close to Tampa would keep the storm too close to land for significant intensification to occur. I put the odds of a mass evacuation being ordered for Tampa during the convention at 1%. I have detailed information on Tampa's storm surge vulnerability in a post from last week.

Invest 97L off the coast of Africa
A tropical wave that moved off the coast of Africa on Thursday has been designated Invest 97L by NHC this morning. The storm has a modest amount of spin and heavy thunderstorms, and is under moderate wind shear of 10 - 20 knots. In their 8 am EDT Tropical Weather Outlook, NHC gave 97L a 30% chance of developing by Sunday morning. The 8 am EDT SHIPS model forecast predicts that 97L will track west-northwest over the next few days, and encounter a region of high wind shear associated with an upper-level low on Monday and Tuesday. This low may be capable of tearing the storm apart, as happened to Tropical Storm Joyce. None of the models currently foresee that 97L will affect the Lesser Antilles Islands, but 97L may pass near Bermuda 7 - 8 days from now.



20th anniversary of Hurricane Andrew
Today, August 24, is the 20th anniversary of Hurricane Andrew, which hit South Florida as a Category 5 hurricane with 175 mph winds--one of only three Category 5 hurricanes ever to hit the U.S. With Isaac churning through the Caribbean this week, I didn't have time to prepare a special post on Andrew, but our Hurricane Andrew archive page has links to satellite and radar images, newspaper headlines, and 49 YouTube videos. Here's an additional link for an Andrew damage video shot by wunderblogger/storm chaser Mike Theiss, when he was 14 years old.

Jeff Masters

Hurricane

The views of the author are his/her own and do not necessarily represent the position of The Weather Company or its parent, IBM.

Reader Comments

Quoting gustavcane:
THE 06Z/12Z GFS AND 12Z CANADIAN SOLUTIONS HAD TO
BE THROWN OUT BY DEFAULT.

That may be why Jim Cantore 
is on the central gulf coast and not in or near florida.

jim cantore is on TWC right now
Quoting Grothar:
So should I stop posting this or what?



Yes Gro! You know that was thrown out because it was wrong :-b
Quoting HCW:
that's pretty good agreement for this far out



wunderkidcayman better pay attention to the XTRP model...
1504. FLSurf
Quoting CloudGatherer:
...and there we go. The hunter has curved all the way around to a northwestern heading, and is commencing a second pass through the center of the circulation. Much weaker winds in this southeastern quadrant - none on the surface that would justify even a tropical storm. Pressure down to 999MB, and temps steady at 17C. The next message should tell us just how fast Isaac is strengthening now.



DO YOU HAVE A LINK TO THESE "MESSAGES"
?
Huh, interesting. Consensus now saying it will only briefly make landfall in Cuba now.. greatly reducing the time it will have to spend over Cuba, NHC is probably going to shift slightly north.
Quoting GTcooliebai:
What it looks like based on those models is the High builds in and the trough is enough to erode the Northwestern Flank of the High and create a weakness pulling it Northeast. The Euro is by itself and has the storm after it makes landfall going Northwest.
The Euro did the same thing with Debbie had it going west and the GFS was right all the time with Debbie
1507. FOREX
Quoting tornadolarkin:
The fact that Isaac still hasn't organized is blowing my mind.


It is a lot better organized than 72 hours ago. Looks like some more slow strengthening then some weakening over Cuba, then stronger again after re-emerging into the Gulf.
Quoting StormTracker2K:
This is the worst case scenario for FL as the NHC again follows the Euro while a storm comes to FL and people get complacent as the local mets say we are in the clear. Very Very bad reasoning here.

NHC will have no choice but to adjust the track to hug the SW FL coast either at 5pm or 11pm.




Chill man, the NHC isn't following the euro, back with Debby the euro had a consensus backing it and the GFS was the outlier. Debby was a very interesting situation where their was almost an equal chance of Debby going either way, it was only reasonable to choose the model consensus. Here the NHC is choosing the consensus, they aren't following the euro and have already shifted their track to the right twice today. It may shift slightly more to the right but nothing drastic which is again reasonable. Think about it professionally, it makes sense they do things the way they do. They try their best to be fair and balanced unlike the media, politics, or many in this blog. Because they have no agenda at stake, they are their to inform people the best they can. Yes they get it wrong sometimes and i don't always agree with them either, but they do a great job.
Time: 19:52:00Z
Coordinates: 16.7833N 71.6W
Acft. Static Air Press: 842.9 mb (~ 24.89 inHg)
Acft. Geopotential Hgt: 1,452 meters (~ 4,764 feet)
Extrap. Sfc. Press: 995.5 mb (~ 29.40 inHg)
D-value: -
Flt. Lvl. Wind (30s): From 239° at 13 knots (From the WSW at ~ 14.9 mph)
Air Temp: 18.0°C* (~ 64.4°F*)
Dew Pt: 18.0°C* (~ 64.4°F*)
Peak (10s) Flt. Lvl. Wind: 15 knots (~ 17.2 mph)
SFMR Peak (10s) Sfc. Wind: 24 knots (~ 27.6 mph)
SFMR Rain Rate: 6 mm/hr (~ 0.24 in/hr)
(*) Denotes suspect data
1510. Grothar
Quoting StormTracker2K:


Gro the experts said to throw it out. Idiots!


Nobody listens to old people anymore. :)

Quoting galvestonhurricane:


wunderkidcayman better pay attention to the XTRP model...


lol
Quoting stormpetrol:


To be honest I never read where he said that about Isaac! BTW , laugh at him, criticize him, make fun of him, but he has been fairly accurate with the movement of Isaac so far, nuff said!


it was me quoting you on the steering I think it was I said steering at Isaac's level shows more W-WNW track and that was it I didn't even say cayman and this guy just goes crazy I truly think there is something wrong with him he is hearing and seeing storm coming to cayman I have no idea where he is pulling this out from his head ... or the rear... J/K but really Don't know where his is puuling this from


Quoting Hurricane1956:
It is not going to the Caymans. It is not going to the Caymans. It is not going to the Caymans. It is not going to the Caymans. It is not going to the Caymans. It is not going to the Caymans. It is not going to the Caymans. It is not going to the Caymans. It is not going to the Caymans. It is not going to the Caymans. It is not going to the Caymans. It is not going to the Caymans. It is not going to the Caymans. It is not going to the Caymans. It is not going to the Caymans. It is not going to the Caymans. It is not going to the Caymans. It is not going to the Caymans. It is not going to the Caymans. It is not going to the Caymans. It is not going to the Caymans. It is not going to the Caymans. It is not going to the Caymans. It is not going to the Caymans.


STOP THIS INSAINE CRAP GUYS
Quoting wunderkidcayman:


that is very true Taz it is getting quite annoying I never even said cayman and this guy has gone crazy because he his hearing things and seeing thing


All I ask WKC is that when Isaac is north of Cuba that you don't tell us you are seeing it moving south:)

btw, it does look like the Caymans dodged one this time.
1514. Matt74
Quoting presslord:
people on this blog bashing the NHC are an amusement to me....
True statement. The NHC has been money so far. People need to remember, they are the professionals.
Quoting CybrTeddy:
Huh, interesting. Consensus now saying it will only briefly make landfall in Cuba now.. greatly reducing the time it will have to spend over Cuba, NHC is probably going to shift slightly north.

Northwest with a bend back more towards the west-northwest as it approaches Florida. Good job ECMWF.
My point is this Issac is potentially 60 to 72hrs from making landfall in extreme SE FL and the local mets are saying nothing to worry about as the track is a couple hundred miles west of Tampa. So that happens everyone listens to the NHC and we have another Charley situation and people aren't prepared because everyone follows the center line of the NHC track instead of focusing on the come of error. Local mets in Orlando are saying we are in the clear in C FL and may not get much if any rain. Crazy!
1517. bwi
Popping back in for a bit. Haven't scrolled down to see if this has been posted -- if so, sorry for the redundancy.

Product: Air Force Vortex Message (URNT12 KNHC)
Transmitted: 24th day of the month at 19:05Z
Aircraft: Air Force Aircraft (Last 3 digits of the tail number are 300)
Storm Number & Year: 09L in 2012
Storm Name: Isaac (flight in the North Atlantic basin)
Mission Number: 12
Observation Number: 02
A. Time of Center Fix: 24th day of the month at 18:43:50Z
B. Center Fix Coordinates: 16°48'N 71°31'W (16.8N 71.5167W) (View map)
B. Center Fix Location: 132 miles (212 km) to the SSE (156°) from Port-au-Prince, Haiti.
C. Minimum Height at Standard Level: 1,381m (4,531ft) at 850mb
D. Estimated (by SFMR or visually) Maximum Surface Wind: 55kts (~ 63.3mph)
E. Location of the Estimated Maximum Surface Wind: 49 nautical miles (56 statute miles) to the ENE/E (79°) of center fix
F. Maximum Flight Level Wind Inbound: From 155° at 70kts (From the SSE at ~ 80.6mph)
G. Location of Maximum Flight Level Wind Inbound: 68 nautical miles (78 statute miles) to the ENE (75°) of center fix
H. Minimum Sea Level Pressure: 995mb (29.38 inHg)
I. Maximum Flight Level Temp & Pressure Altitude Outside Eye: 14°C (57°F) at a pressure alt. of 1,524m (5,000ft)
J. Maximum Flight Level Temp & Pressure Altitude Inside Eye: 18°C (64°F) at a pressure alt. of 1,525m (5,003ft)
K. Dewpoint Temp (collected at same location as temp inside eye): 16°C (61°F)
K. Sea Surface Temp (collected at same location as temp inside eye): Not Available
L. Eye Character: Not Available
M. Eye Shape: Not Available
N. Fix Determined By: Penetration, Wind, Pressure and Temperature
N. Fix Levels (sfc and flt lvl centers are within 5nm of each other): Surface and 850mb
O. Navigation Fix Accuracy: 0.02 nautical miles
O. Meteorological Accuracy: 4 nautical miles
Remarks Section:
Maximum Flight Level Wind: 70kts (~ 80.6mph) in the east quadrant at 18:21:30Z
Quoting RTSplayer:


Wait, what happened that I missed?

I was eating...


That's part of an HPC discussion.
Quoting CybrTeddy:
Huh, interesting. Consensus now saying it will only briefly make landfall in Cuba now.. greatly reducing the time it will have to spend over Cuba, NHC is probably going to shift slightly north.




winds up too 65mph i see
Quoting galvestonhurricane:


wunderkidcayman better pay attention to the XTRP model...


no I will not
XTRP is not a model
Quoting Jedkins01:


Yeah I think the GFDL is pretty much the consensus between the far right and far left models right now.

Wait, the models are based on conservative and liberal ideologies? Oh no! We're in trouble!
Nonsense, Grothar... I've been listening to you for years here on the blog.... :-)

Always interested in your analysis :)
Quoting StormTracker2K:


Gro the experts said to throw it out. Idiots!


You need to read between the lines of what HPC said. It is like two departments in a company, hurricanes belong to NHC so HPC cannot disagree with what they say, it is not their job. So since those models do not agree with the current NHC track, they need to be thrown out by default. See what NHC says at 5 PM.
TS watches COULD be issued for the Keys in this upcoming advisory.
Quoting StormTracker2K:


This is getting ridiculous already. THe NHC and HPC are going to get burned again. They never learn throw the GFS out when it's been the best performing model!


Yeah, I'm not quite sure why they start out really favoring the GFS and now it's almost like the sexier ECMWF model came along and they just dumped poor ol' GFS and won't even look at her anymore...
1526. bappit
Quoting gulfbreeze:
The H/center has it moving N/W looks more like a WNW to me. Could he be bumping the Mtr. Range?

Finally that expression makes sense to me.
Quoting FOREX:


The two Hurricane experts on TWC just said the center is moving WNW. go figure.
DAHHH.....Did they mention west as a possibility?? hahahahaha
Pressure Still about 995.
Not quite at centerfix yet.

Time: 19:52:00Z
Coordinates: 16.7833N 71.6W
Acft. Static Air Press: 842.9 mb (~ 24.89 inHg)
Acft. Geopotential Hgt: 1,452 meters (~ 4,764 feet)
Extrap. Sfc. Press: 995.5 mb (~ 29.40 inHg)
D-value: -
Flt. Lvl. Wind (30s): From 239° at 13 knots (From the WSW at ~ 14.9 mph)
Air Temp: 18.0°C* (~ 64.4°F*)
Dew Pt: 18.0°C* (~ 64.4°F*)
Peak (10s) Flt. Lvl. Wind: 15 knots (~ 17.2 mph)
SFMR Peak (10s) Sfc. Wind: 24 knots (~ 27.6 mph)
SFMR Rain Rate: 6 mm/hr (~ 0.24 in/hr)
(*) Denotes suspect data
1529. A4Guy
I think it should be mandatory to have your location included as part of your screen name. It would explain a LOT - especially with the home-drawn forecasts. I am sure 90% of them take the storm to the poster's doorstep. Would also expose those screaming "it's going West...not Northwest" - it will be no surprise that the direction being advocated similarly takes the storm to their house (or on a path in their general direction).
Quoting clwstmchasr:


All I ask WKC is that when Isaac is north of Cuba that you don't tell us you are seeing it moving south:)

btw, it does look like the Caymans dodged one this time.


I have no idea what you think I would say that

Quoting CloudGatherer:
...and there we go. The hunter has curved all the way around to a northwestern heading, and is commencing a second pass through the center of the circulation. Much weaker winds in this southeastern quadrant - none on the surface that would justify even a tropical storm. Pressure down to 999MB, and temps steady at 17C. The next message should tell us just how fast Isaac is strengthening now.


I think the key word is "strengthening."

Just as it took a lot of energy, and time, to get Isaac spinning, Isaac is now spinning, and Isaac is big.

Meaning, the mountains of Hispanola and Cuba won't disrupt it as much, and when he gets to the GOM,
expect unexpected intensification.

Just my 2.
Quoting Grothar:
So should I stop posting this or what?



Keep on posting :)
1533. Grothar
Quoting ProgressivePulse:


Yes Gro! You know that was thrown out because it was wrong :-b


I guess I'll stop mentioning the Windward Passage and the far Eastern Coast of Cuba, too. :)



yea...those NHC guys are a bunch of losers....they should trade in their education, reputations, years of experience, virtually unlimited budgets, cutting edge technology...and just lay around their Mother's house in their dirty underwear, scratching their crotches and and posting to this blog...then they'd get some respect...
Quoting Tazmanian:




winds up too 65mph i see


May be up to 70 before it briefly makes landfall in Haiti.
Reason NHC is on the far west side is because of the short term WNW track which is what you're seeing on the Xtrap direction. The model consensus is already taking it NW which is not the current direction. Therefore the NHC must stay on the west side of the models. (In other words, the direction the models are moving it are already friggin wrong)

Quoting tropicfreak:


May be up to 70 before it briefly makes landfall in Haiti.



hmmm more overe water the stronger it gets
Quoting Grothar:


I guess I'll stop mentioning the Windward Passage and the far Eastern Coast of Cuba, too. :)





What an outlier you are man. Spreading truth like you own it.
Quoting Matt74:
True statement. The NHC has been money so far. People need to remember, they are the professionals.


Mostly yes, but they had serious egg on their face with Debby and it was all self inflicted. Giving up on the GFS so soon was moronic. It's almost like the new director Rick Knabb has a fixation on the Euro. Oh well...they are usually right so for now I'll just keep a guarded eye on things. I'm sure we'll get TS conditions either way in Fort Myers and we've already picked up everything outside and shuttered some windows so we're good.
Quoting Grothar:


Nobody listens to old people anymore. :)



I do! They tell the BEST stories!

Seriously though... interesting how some of the models are skirting Cuba's northern coast now. That would tend to help Isaac maintain any strength, since his circulation would inhibit him a bit from making full landfall in Cuba, and he would also have his whole right side over toasty waters.
Quoting CybrTeddy:
Huh, interesting. Consensus now saying it will only briefly make landfall in Cuba now.. greatly reducing the time it will have to spend over Cuba, NHC is probably going to shift slightly north.

Which means a skim of SW florida as it head NW. and this also means much greater strengthening..
Expect at Category 1 landfall on SW and Category 2/3 On Eastern Gulf Coast, if this consensus verifies.
Dropsonde "in the eye" finds 995mb - so that'll be the reading at the next advisory.
1543. A4Guy
Quoting presslord:
yea...those NHC guys are a bunch of losers....they should trade in their education, reputations, years of experience, virtually unlimited budgets, cutting edge technology...and just lay around their Mother's house in their dirty underwear, scratching their crotches and and posting to this blog...then they'd get some respect...


lol....you sound just like me, except I usually say "pajamas" instead of "dirty underwear."
Navy site says Isaac is at 55knts
Quoting wunderkidcayman:


no I will not
XTRP is not a model


I know you won't. It was a joke.


wunderkidcayman what do you think about the HWRF track here?
995 mb? Impressive... we'll see what this next path does.
Quoting bwi:
I. Maximum Flight Level Temp & Pressure Altitude Outside Eye: 14°C (57°F) at a pressure alt. of 1,524m (5,000ft)
J. Maximum Flight Level Temp & Pressure Altitude Inside Eye: 18°C (64°F) at a pressure alt. of 1,525m (5,003ft)

Hmm... core warming up a bit, a good sign of organization.
Quoting StormTracker2K:
My point is this Issac is potentially 60 to 72hrs from making landfall in extreme SE FL and the local mets are saying nothing to worry about as the track is a couple hundred miles west of Tampa. So that happens everyone listens to the NHC and we have another Charley situation and people aren't prepared because everyone follows the center line of the NHC track instead of focusing on the come of error. Local mets in Orlando are saying we are in the clear in C FL and may not get much if any rain. Crazy!


ST2K calm down. Did you read the rest of the discussion? It's about the affects of Isaac. Nobody's ignoring the danger Florida's facing. Here's a line from it and a link.

(SIMILAR TO DEBBY
IN LATE JUNE BUT FARTHER TO THE WEST)
Link
Given that the TVCN (model consensus) has shifted quite a bit further north and east at least in the first 48 to near 72 hour time frame, I believe the NHC will have to adjust their track accordingly bringing the storm into the Keys during that time frame. This would warrant the issuance of Tropical Storm watches and warnings.
Quoting nrtiwlnvragn:


You need to read between the lines of what HPC said. It is like two departments in a company, hurricanes belong to NHC so HPC cannot disagree with what they say, it is not their job. So since those models do not agree with the current NHC track, they need to be thrown out by default. See what NHC says at 5 PM.


Oh I see. I am just aggitated watching the news and the media is telling the public C and S FL will little to worry about as the track is shifting west. The NHC shifted there track west twice today while the model consensus has shifted right twice. Erin in 1995 was also a prime example as folks in Melbourne only had 12hrs to prepare for a hurricane when the NHC said it was going to Miami.
Can anyone tell me what the latest Euro run is please and thank you. :)
1553. Grothar
5pm should be 65-70mph and 995mb pressure
994.2 Just a little bit stronger.
Quoting cchsweatherman:
Given that the TVCN (model consensus) has shifted quite a bit further north and east at least in the first 48 to near 72 hour time frame, I believe the NHC will have to adjust their track accordingly bringing the storm into the Keys during that time frame. This would warrant the issuance of Tropical Storm watches and warnings.

Yep. The NHC loves to follow the TVCN, but I've also seen them manually make a consensus, removing some of the outliers.
The lowest implied pressure reading on this pass was 994.2 - but the NHC prefers to rely on dropsondes, even if it was dropped a little far south of that reading. I suspect the Vortex and the advisory will both use 995 instead.

Much more interestingly, the temperate in the core of the storm has risen all the way up to 19C - that increasing differential is the best indication we've had of eye formation.
Quoting caribnewsman:


Actually, the southern edge of the NHC cone, which is much like the EURO, takes the center of a very large cyclone very close to Cayman Brac and Little Cayman. Although they wouldn't get the dirty side of Isaac, if the storm takes the southern edge of the 3-day cone track - which is certainly in the realm of possibility according to the NHC - the "Caymans" will get pounded. So ease up dude.


The Caymans...is that like "The Carolinas"?
It's now 994 mb.

Time: 19:58:00Z
Coordinates: 17.0333N 71.8333W
Acft. Static Air Press: 843.1 mb (~ 24.90 inHg)
Acft. Geopotential Hgt: 1,444 meters (~ 4,738 feet)
Extrap. Sfc. Press: 994.2 mb (~ 29.36 inHg)
D-value: -
Flt. Lvl. Wind (30s): From 11 at 17 knots (From the N/NNE at ~ 19.5 mph)
Air Temp: 19.0C (~ 66.2F)
Dew Pt: 18.4C (~ 65.1F)
Peak (10s) Flt. Lvl. Wind: 18 knots (~ 20.7 mph)
SFMR Peak (10s) Sfc. Wind: 23 knots (~ 26.4 mph)
SFMR Rain Rate: 4 mm/hr (~ 0.16 in/hr)
I was wanting to share something I thought is interesting.

All week it has been raining here in South West Georgia with showers and storms but all of the sudden skies have clear and the system causing the rain is moving out just in time for Isaac. It makes you wonder if ole isaac has something to do with that.

*hey move out of the way...I am coming through*
Quoting StormTracker2K:
My point is this Issac is potentially 60 to 72hrs from making landfall in extreme SE FL and the local mets are saying nothing to worry about as the track is a couple hundred miles west of Tampa. So that happens everyone listens to the NHC and we have another Charley situation and people aren't prepared because everyone follows the center line of the NHC track instead of focusing on the come of error. Local mets in Orlando are saying we are in the clear in C FL and may not get much if any rain. Crazy!


Oh well they should be alright (CAT 1 tops according to forecast) unless of course Isaac blows up rather quickly
Quoting clwstmchasr:


All I ask WKC is that when Isaac is north of Cuba that you don't tell us you are seeing it moving south:)

btw, it does look like the Caymans dodged one this time.


The caymans haven't dodged anything. The still are on the left side of the storm and have a storm moving in a direction north of them. Any turn to the south and west changes everything. I believe they have the right to breath a bit easier but NEVER let your guard down. Weather is unpredictable. They aren't out of the woods until the storm passes over Cuba and is in the GOM.
I'm at work. Can someone link me the latest European model animated. Thanks - I check back from time to time
If I was an admin, I'd without a shadow of a doubt permanently ban anyone that labeled someone else as a "***-caster". Seriously lol.
Quoting ChaseyChasinStorms:
Can anyone tell me what the latest Euro run is please and thank you. :)

994.2 millibars with 23 knot surface winds.

Using the wind/pressure relationship, Isaac has a barometric pressure of around 992 millibars.
Quoting JrWeathermanFL:
5pm should be 65-70mph and 995mb pressure


Maybe 994 mb pressure even.
Quoting JrWeathermanFL:
5pm should be 65-70mph and 995mb pressure

I'd actually guess 65mph and 994mb (994 b/c the HH had several extrapolated 994.x readings, and I didn't notice any SFMR readings over 65mph)
1567. bwi
Another drop in the eye -- 994mb

Level Geo. Height Air Temp. Dew Point Wind Direction Wind Speed
994mb (29.35 inHg) Sea Level (Surface) 26.2°C (79.2°F) 24.5°C (76.1°F) 20° (from the NNE) 2 knots (2 mph)
1000mb -49m (-161 ft) This level does not exist in this area of the storm above the surface level.
925mb 637m (2,090 ft) 22.4°C (72.3°F) 21.0°C (69.8°F) 270° (from the W) 3 knots (3 mph)
850mb 1,372m (4,501 ft) 19.2°C (66.6°F) 18.3°C (64.9°F) 350° (from the N) 2 knots (2 mph)

Information About Radiosonde:
- Launch Time: 19:55Z
- About Sonde: A descending radiosonde tracked automatically by satellite navigation with no solar or infrared correction.

Remarks Section...

Dropsonde Location: Dropped in eye.

Splash Location: 16.91N 71.71W
Splash Time: 19:57Z

Release Location: 16.91N 71.71W View map)
Release Time: 19:55:01Z

Splash Location: 16.91N 71.71W (
Splash Time: 19:56:14Z

Mean Boundary Level Wind (mean wind in the lowest 500 geopotential meters of the sounding):
- Wind Direction: 0° (from the N)
- Wind Speed: 0 knots (0 mph)
Quoting MiamiHurricanes09:
If I was an admin, I'd without a shadow of a doubt permanently ban anyone that labeled someone else as a "***-caster". Seriously lol.

Bancaster...
Pressure down to 994 MB.
Level Geo. Height Air Temp. Dew Point Wind Direction Wind Speed
994mb (29.35 inHg) Sea Level (Surface) 26.2°C (79.2°F) 24.5°C (76.1°F) 20° (from the NNE) 2 knots (2 mph)
1000mb -49m (-161 ft) This level does not exist in this area of the storm above the surface level.
925mb 637m (2,090 ft) 22.4°C (72.3°F) 21.0°C (69.8°F) 270° (from the W) 3 knots (3 mph)
850mb 1,372m (4,501 ft) 19.2°C (66.6°F) 18.3°C (64.9°F) 350° (from the N) 2 knots (2 mph
Quoting presslord:
yea...those NHC guys are a bunch of losers....they should trade in their education, reputations, years of experience, virtually unlimited budgets, cutting edge technology...and just lay around their Mother's house in their dirty underwear, scratching their crotches and and posting to this blog...then they'd get some respect...


^THIS

/end thread
1571. Grothar
Quoting jeffs713:


I do! They tell the BEST stories!

Seriously though... interesting how some of the models are skirting Cuba's northern coast now. That would tend to help Isaac maintain any strength, since his circulation would inhibit him a bit from making full landfall in Cuba, and he would also have his whole right side over toasty waters.


Toasty is right.
Quoting MiamiHurricanes09:
If I was an admin, I'd without a shadow of a doubt permanently ban anyone that labeled someone else as a "***-caster". Seriously lol.

You ***-caster!
Quoting ProgressivePulse:
Current motion could also be a little deceiving as the convection just wrapped around the center.



that is a weird looking storm
1574. CJ5
Quoting presslord:
yea...those NHC guys are a bunch of losers....they should trade in their education, reputations, years of experience, virtually unlimited budgets, cutting edge technology...and just lay around their Mother's house in their dirty underwear, scratching their crotches and and posting to this blog...then they'd get some respect...


LOL. Reading this blog, I thought that was who the NHC was.
5 Pm Advisory:
65 Mph
994 MB.


ok now I see why you guys say that well just to let you now even if it did take that path(XTRP) (which it won't) it still won't come to me because I AM NOT THERE I am about 84 miles ESE from there there
Quoting KeyWestwx:
I'm at work. Can someone link me the latest European model animated. Thanks - I check back from time to time


http://raleighwx.americanwx.com/models/euro/00zeu rotropical850mbVortSLP_loop.html
Quoting FOREX:


It is a lot better organized than 72 hours ago. Looks like some more slow strengthening then some weakening over Cuba, then stronger again after re-emerging into the Gulf.


He's almost as bad as Ernesto. He doesn't really look too bad right now, but he doesn't have very much strong convection. I actually think once he gets his act together he'll be stronger than the NHC believe's he will be.
Quoting A4Guy:
I think it should be mandatory to have your location included as part of your screen name. It would explain a LOT - especially with the home-drawn forecasts. I am sure 90% of them take the storm to the poster's doorstep. Would also expose those screaming "it's going West...not Northwest" - it will be no surprise that the direction being advocated similarly takes the storm to their house (or on a path in their general direction).
I have been advocating the wsw-w-wnw for a while based on the steering maps. I happen to live in a sheetmetal box not able to stand up to 100 mph winds and have my valubles loaded and ready to leave state.No, I don't wishcast,I call 'em the way I see 'um.
1581. FOREX
Quoting ChaseyChasinStorms:
Can anyone tell me what the latest Euro run is please and thank you. :)


I believe it has landfall in Biloxi.
Quoting RitaEvac:
Reason NHC is on the far west side is because of the short term WNW track which is what you're seeing on the Xtrap direction. The model consensus is already taking it NW which is not the current direction. Therefore the NHC must stay on the west side of the models. (In other words, the direction the models are moving it are already friggin wrong)



Scratches head in disbelief.


summary of 200 PM EDT...1800 UTC...information ---------------------------------------------- location...16.8n 71.4w about 135 mi...215 km SSE of Port au Prince Haiti about 160 mi...255 km SW of Santo Domingo Dominican Republic maximum sustained winds...60 mph...95 km/h present movement...NW or 305 degrees at 14 mph...22 km/h minimum central pressure...997 mb...29.44 inches
Read more at http://www.wunderground.com/tropical/at201209.publ ic.html#rgCDtQeWYqJyDgfG.99
Quoting presslord:
yea...those NHC guys are a bunch of losers....they should trade in their education, reputations, years of experience, virtually unlimited budgets, cutting edge technology...and just lay around their Mother's house in their dirty underwear, scratching their crotches and and posting to this blog...then they'd get some respect...

Wish there was a way to plus comments more than once, lol.
My local mets in SWF have changed their story and are now very worried for this area. Conditions "could" be going down hill as early as Sunday afternoon". I really can't post my thoughts right now
1585. ncstorm
Quoting presslord:
yea...those NHC guys are a bunch of losers....they should trade in their education, reputations, years of experience, virtually unlimited budgets, cutting edge technology...and just lay around their Mother's house in their dirty underwear, scratching their crotches and and posting to this blog...then they'd get some respect...


now press, I have to disagree with you there..

anyone living in their mother house will not have dirty underwear..
Quoting MiamiHurricanes09:
If I was an admin, I'd without a shadow of a doubt permanently ban anyone that labeled someone else as a "***-caster". Seriously lol.


You Bancaster!!!!
Quoting wunderkidcayman:


ok now I see why you guys say that well just to let you now even if it did take that path(XTRP) (which it won't) it still won't come to me because I AM NOT THERE I am about 84 miles ESE from there there
The models are all east of the NHC track except the UKMET and ECMWF.
NASA's picture of TS Isaac at 3 pm

dont they usually skip right to 70mph?
Quoting MiamiHurricanes09:
If I was an admin, I'd without a shadow of a doubt permanently ban anyone that labeled someone else as a "***-caster". Seriously lol.


He'd need to ban at least half of his paying members to accomplish that, so that's not gonna happen.
Quoting Grothar:


Nobody listens to old people anymore. :)



awe Grothar - we've been listening to you for years, and years, and...
NHC losing their marbles if there isn't a considerble eastward shift in the forecast cone.
1593. CJ5
Quoting CJ5:


LOL. Reading this blog, I thought that was who the NHC was.


...and don't forget the HH. That is just Charlie Brown and Snoopy flying around in a Sopwith Camel throwing dog bowls out the cockpit.
Quoting MiamiHurricanes09:
If I was an admin, I'd without a shadow of a doubt permanently ban anyone that labeled someone else as a "***-caster". Seriously lol.


Miami what is your thinking of the models taking this to southern FL while the NHC is much further south than the guidance? What is the feeling there in MIA? Is the media properly informing people are are they being conservative as the mets in Orlando are?


Quoting hurricanejunky:


Yeah, I'm not quite sure why they start out really favoring the GFS and now it's almost like the sexier ECMWF model came along and they just dumped poor ol' GFS and won't even look at her anymore...


maybe it is because it can not make up its mind and stop flip flopping all over the place lol.

Saw CBS 12 at the Palm Beach County EOC when I drove by it this afternoon.
Quoting presslord:
yea...those NHC guys are a bunch of losers....they should trade in their education, reputations, years of experience, virtually unlimited budgets, cutting edge technology...and just lay around their Mother's house in their dirty underwear, scratching their crotches and and posting to this blog...then they'd get some respect...



You've just won the weather blog.
1599. CJ5
Quoting ChaseyChasinStorms:
Can anyone tell me what the latest Euro run is please and thank you. :)


No much change, page back a page or two and it is on here.
Quoting MiamiHurricanes09:
NHC losing their marbles if there isn't a considerble eastward shift in the forecast cone.
Thank you I wouldn't have been so kind right now..
Quoting weatherman12345:
dont they usually skip right to 70mph?
They skip 55mph.
Welcome to Florida ...we have been expecting you.

I am jumping on the bandwagon(didn't think he would make it), Isaac is getting serious now. Will be Hurricane Isaac by 2am giving the current intensification...close to 994mb now and moving NW...

Levi's track seems very reasonable. Best dude we have on this blog.
Quoting DrMickey:


The Caymans...is that like "The Carolinas"?


not really....

There is a lot more American money in the Caymans....

; )
1604. hulakai
Hey WKC, those folks are just pokin ya in the ribs. Just laugh (like levi) and they will go away. Keep watchin and expressin yer opinion and you'll learn as ya go along.

I'm 60 and been watchin fer a long time and I still learn something in here every day!

Could be one day, like doc and NHC folks will value your opinion over their own.

Meanwhile, wind is freshening here in Broward from NE

Quoting A4Guy:
I think it should be mandatory to have your location included as part of your screen name. It would explain a LOT - especially with the home-drawn forecasts. I am sure 90% of them take the storm to the poster's doorstep. Would also expose those screaming "it's going West...not Northwest" - it will be no surprise that the direction being advocated similarly takes the storm to their house (or on a path in their general direction).



I do have my location in my handle and I agree with you. been that way from the beginning here.

I am very much behind for past hour... need to catch up..
The most significant thing about the 18z model run suite (for me) was the fact that the model consensus now is now the TVCA is, like we mentioned, only showing Isaac briefly making landfall with Cuba instead of traversing half the length of the island as the NHC has it doing. The TVCA for those who don't know much about the models, is the mean or average of all the model runs. You will often find that the NHC follows usually pretty close to the TVCA.
1607. FOREX
Quoting masonsnana:
Thank you I wouldn't have been so kind right now..


If the GFS showed Isaac going up the spine of Florida I could see a cone shift East.
Quoting wolftribe2009:
I was wanting to share something I thought is interesting.

All week it has been raining here in South West Georgia with showers and storms but all of the sudden skies have clear and the system causing the rain is moving out just in time for Isaac. It makes you wonder if ole isaac has something to do with that.

*hey move out of the way...I am coming through*

Oh well they should be alright (CAT 1 tops according to forecast) unless of course Isaac blows up rather quickly

The caymans haven't dodged anything. The still are on the left side of the storm and have a storm moving in a direction north of them. Any turn to the south and west changes everything. I believe they have the right to breath a bit easier but NEVER let your guard down. Weather is unpredictable. They aren't out of the woods until the storm passes over Cuba and is in the GOM.


hmm that is true

this is how I put it We here in the Cayman Islands are not out of the woods yet I'd say we wouldn't be out till it NNW of us anything can happens so just keep an eye out




looks like HH found next fix WNW-NW of last fix
Well comparing 2pm NHC advisory to latest dropsonde, Isaac has moved .1N and .3W, back to a WNW movement.
1610. LargoFl
all of a sudden..sand bags are like GOLD you have to show ID to get them?..............PINELLAS COUNTY

Sandbags will be available Saturday and Sunday from 8 a.m. to 5 p.m., weather permitting. Residents must have identification that verifies they are residents of St. Petersburg. Twenty bags per vehicle allowed.

Northeast Park, 875 62nd Avenue NE at the Cardinal Drive entrance to Mangrove Bay Course
Frank W. Pierce Recreation Center, 2000 Seventh St. St, enter from 22nd Ave. S., east side of Seventh Street
Product: Air Force Vortex Message (URNT12 KNHC)
Transmitted: 24th day of the month at 20:03Z
Aircraft: Air Force Aircraft (Last 3 digits of the tail number are 300)
Storm Number & Year: 09L in 2012
Storm Name: Isaac (flight in the North Atlantic basin)
Mission Number: 12
Observation Number: 06
A. Time of Center Fix: 24th day of the month at 19:54:50Z
B. Center Fix Coordinates: 16°54'N 71°42'W (16.9N 71.7W) (View map)
B. Center Fix Location: 121 miles (195 km) to the SSE (160°) from Port-au-Prince, Haiti.
C. Minimum Height at Standard Level: 1,378m (4,521ft) at 850mb
D. Estimated (by SFMR or visually) Maximum Surface Wind: 31kts (~ 35.7mph)
E. Location of the Estimated Maximum Surface Wind: 27 nautical miles (31 statute miles) to the SE (139°) of center fix
F. Maximum Flight Level Wind Inbound: From 237° at 34kts (From the WSW at ~ 39.1mph)
G. Location of Maximum Flight Level Wind Inbound: 34 nautical miles (39 statute miles) to the SE (140°) of center fix
H. Minimum Sea Level Pressure: 994mb (29.35 inHg)
I. Maximum Flight Level Temp & Pressure Altitude Outside Eye: 17°C (63°F) at a pressure alt. of 1,525m (5,003ft)
J. Maximum Flight Level Temp & Pressure Altitude Inside Eye: 18°C (64°F) at a pressure alt. of 1,524m (5,000ft)
K. Dewpoint Temp (collected at same location as temp inside eye): 18°C (64°F)
K. Sea Surface Temp (collected at same location as temp inside eye): Not Available
L. Eye Character: Not Available
M. Eye Shape: Not Available
N. Fix Determined By: Penetration, Wind, Pressure and Temperature
N. Fix Levels (sfc and flt lvl centers are within 5nm of each other): Surface and 850mb
O. Navigation Fix Accuracy: 0.02 nautical miles
O. Meteorological Accuracy: 2 nautical miles
Remarks Section:
Maximum Flight Level Wind: 70kts (~ 80.6mph) in the east quadrant at 18:21:30Z
None of these models go any further west then the FL/AL border. Not sure why the cone is that far west now...

Quoting StormTracker2K:


Miami what is your thinking of the models taking this to southern FL while the NHC is much further south than the guidance? What is the feeling there in MIA? Is the media properly informing people are are they being conservative as the mets in Orlando are?

I haven't been able to watch the news, I'm actually in a hospital waiting room on my iPad lol, but I'd assume that the news stations aren't reacting to the model runs. However, once the cone gets shifted in accordance to the runs, I could really see the outlets hyping the situation...like they always do. The possibility of a hurricane making landfall over the northern Keys as well as Dade county is high.
Quoting Thing342:
They skip 55mph.


there can't be 55 mph
1615. bwi
.
Quoting BoroDad17:
Well comparing 2pm NHC advisory to latest dropsonde, Isaac has moved .1N and .3W, back to a WNW movement.
That's what they do,wobble in a general direction.
Quoting CaicosRetiredSailor:


not really....

There is a lot more American money in the Caymans....

; )

Perfect!
1618. Grothar
Quoting ProgressivePulse:


What an outlier you are man. Spreading truth like you own it.



I can't help myself.
1619. Levi32
Holy cow! GOES-14 brought out of storage and running 1-min data until October, currently focused on Isaac!

1-min super rapid scan visible loop
1620. sdswwwe
Is that an eye-like feature on Isaac?
so is the cone shifting east at 5? Sorry been gone all day.
Quoting MiamiHurricanes09:
I haven't been able to watch the news, I'm actually in a hospital waiting room on my iPad lol, but I'd assume that the news stations aren't reacting to the model runs. However, once the cone gets shifted in accordance to the runs, I could really see the outlets hyping the situation...like they always do. The possibility of a hurricane making landfall over the northern Keys as well as Dade county is high.


Everything Ok?
Rough Google Earth estimate based on the 2 VDM:

300 degrees at 12 mph.
1624. CJ5
Quoting sdswwwe:
Is that an eye-like feature on Isaac?


No, it is not.
1625. LargoFl
ARASOTA --
Pasco County has joined Sarasota County in declaring a local state of emergency ahead of Tropical Storm Isaac's potential impact.
Pasco County
Pasco Co. officials said the county's Emergency Management is in "constant contact with state and regional emergency agencies."

Officials encourages those in the county to contact the Resident Information Center at 727-847-2411/8959 for information. The RIC open from 7 a.m. to 7 p.m. The center is there "to assist residents and visitors' preparation for the approaching severe weather," officials said.
Sarasota County
According to a statement Thursday afternoon, the Sarasota County Emergency Operations Center is at a" Level 3 monitoring status" as Isaac moves through the Caribbean on a general path toward the southwest Florida area.
Isaac's Latest Track

"Declaring a local state of emergency is a proactive measure to allow Sarasota County to be prepared for any unforeseen expenditures due to the storm," the county said, "and to use the county's emergency operations plans." The reasoning applies to Pasco and any other counties that may declare states of emergency ahead of Isaac.
Officials said the declaration provides the county the authority to coordinate the allocation of resources in protecting the community, critical infrastructure and general welfare of citizens and visitors.

"Residents should continue to pay close attention to local news media for updates on the situation. Additional flooding, tornado warnings or other urgent updates can happen as Tropical Storm Isaac moves toward the southwest coast of Florida," officials said.
If you have questions, you can contact the Sarasota County Call Center at 941-861-5000, or visit www.scgov.net and click on the "All Hazards" link.
Quoting Levi32:
Holy cow! GOES-14 brought out of storage and running 1-min data until October, currently focused on Isaac!

1-min super rapid scan visible loop


Not to sound off topic too much, I was there for the GOES-14 (then GOES-O) launch in person. Link You can tell by 19 seconds into the video what I was really there for ;)
There's ur eye, errr dry slot I mean..

Quoting Levi32:
Holy cow! GOES-14 brought out of storage and running 1-min data until October, currently focused on Isaac!

1-min super rapid scan visible loop



now that's pretty awesome.
Quoting Levi32:
Holy cow! GOES-14 brought out of storage and running 1-min data until October, currently focused on Isaac!

1-min super rapid scan visible loop


VERY COOL!
Quoting presslord:
yea...those NHC guys are a bunch of losers....they should trade in their education, reputations, years of experience, virtually unlimited budgets, cutting edge technology...and just lay around their Mother's house in their dirty underwear, scratching their crotches and and posting to this blog...then they'd get some respect...


Fanboy!
Quoting angiest:
hurricanealley.net (not official)




I don't think it can get that far west due to the high pressure ridge in mexico, the low setting up in the GoM, and the steering winds from the high to the northeast of Isaac in the Atlantic

I do see it making it past Haiti and DR without making a landfall with either the surface low or the deepening mid level around 16N 71W.,.....and I think this is now slowing down and pulling itself together, or in other words, aligning vertically by aligning mid and low level windfields....I honestly see it making a beeline for Jamaica and staying over water with the center under Cuba as it heads to Western Cuba.....At a point it is gonna want to turn hard north as it feels the MJO in the GoM and the high ridge in the atlantic.....
Isaac doesn't want to go over those mountains unless he has to. Path of least resistance is through the passage. Interested to see the motion once he gets there.
Afternoon everyone, FPL is in full storm prep mode. Working an extra day tomorrow, and possibly doubles this coming week(that's up to Isaac), I see the models are holding steady with the solution to scrape SWFL before continuing on to the panhandle. Should be interesting to see how much land Isaac interacts with...
Quoting Levi32:
Holy cow! GOES-14 brought out of storage and running 1-min data until October, currently focused on Isaac!

1-min super rapid scan visible loop


Now THAT is awesome.
I don't see the cone changing much in the 5pm due to the Euro staying so far west. Intensity will bump up to 65-70mph though.
Eye see an eye in Eyesaac.
Quoting Levi32:
Holy cow! GOES-14 brought out of storage and running 1-min data until October, currently focused on Isaac!

1-min super rapid scan visible loop


just beautiful...
Link

Heres a cool view if you have a big monitor.
Quoting weatherconch:
so is the cone shifting east at 5? Sorry been gone all day.


It very well may be shifting east at 5. Which everyone doesn't seem to get. But we'll have to wait and see.
Quoting DrMickey:


The Caymans...is that like "The Carolinas"?

Not to the same degree, but it does identify someone as a tourist/foreigner.

The point is, Isaac could very well pass closely to two of the three Cayman Islands just as easily as it could pass very closely to Miami.
1641. WxLogic
Quoting Levi32:
Holy cow! GOES-14 brought out of storage and running 1-min data until October, currently focused on Isaac!

1-min super rapid scan visible loop


Would have been pretty nice if you could pick out the HH planes as they are making their rounds.
1642. HrDelta
Quoting CybrTeddy:
The most significant thing about the 18z model run suite (for me) was the fact that the model consensus now is now the TVCA is, like we mentioned, only showing Isaac briefly making landfall with Cuba instead of traversing half the length of the island as the NHC has it doing. The TVCA for those who don't know much about the models, is the mean or average of all the model runs. You will often find that the NHC follows usually pretty close to the TVCA.


Also, it does make landfall on Haiti, but doesn't stay on land very long.
Quoting Levi32:
Holy cow! GOES-14 brought out of storage and running 1-min data until October, currently focused on Isaac!

1-min super rapid scan visible loop

Thanks for sharing. I appreciate your post.
1644. Grothar
Quoting hurricanejunky:
None of these models go any further west then the FL/AL border. Not sure why the cone is that far west now...



Because about half of those models are crap anyway, and the most reliable model, the Euro, is not on that graphic (for legal reasons,) and it takes the storm much farther west.


Moreover, the consensus output of any one model is not set in stone, that is just the line representing the highest probability calculated by that model's members.

Even the GFS is not one center line. It's lots of members that are all over, though on this particular run the GFS members are closer to it's own consensus than on the two previous runs, still on the previous runs even the GFS had members going far to the west, even outside the cone.

Never mind…looks like a dry slot. Gotta put the vis on loop.
Quoting Levi32:
Holy cow! GOES-14 brought out of storage and running 1-min data until October, currently focused on Isaac!

1-min super rapid scan visible loop


So cool to watch...
There is one thing for sure about Isaac. It is NOT going WEST! 305 degree heading is not West.
Quoting MiamiHurricanes09:
NHC losing their marbles if there isn't a considerble eastward shift in the forecast cone.


Don't know about considerable, they want to avoid the "windshield wiper" affect. I would think a move eastward, at least for South Florida will occur.
Recon vortex data messages have made no remarks about an eyewall forming so there is no eye yet.
Quoting weatherconch:
Link

Heres a cool view if you have a big monitor.


that really puts it into perspective.
Quoting Surferdude:
Welcome to Florida ...we have been expecting you.

I am jumping on the bandwagon(didn't think he would make it), Isaac is getting serious now. Will be Hurricane Isaac by 2am giving the current intensification...close to 994mb now and moving NW...

Levi's track seems very reasonable. Best dude we have on this blog.


Yes, Levi is a class act regardless if you agree with him or not.
1653. wpb
Quoting Levi32:
Holy cow! GOES-14 brought out of storage and running 1-min data until October, currently focused on Isaac!

1-min super rapid scan visible loop
levi watchs for s fla keys at 5pm?
dry air will not be a concern for Isaac within 24-36 hrs as he ramps up. MJO bombing in GoM is making tons of water vapor. SAL pocket in western caribbean is caving inwards from all directions...

Quoting Levi32:


I want FSU, but we'll have to see how that goes.


I lived in Anchorage/ Eagle River, Alaska and was in Jacksonville, Florida on assignment for State Farm and currently live in Spring, Texas. Let me just say I have traveled extensively all over the country and Alaska is by far the best place in the US to live. Especially on the Keni Peninsula. I hope one day I can talk the wife and kids to move up there. The summers sure are better than in Houston or Florida. FSU is a great school tho for meteorology.

Quoting StormTracker2K:


Everything Ok?
Oh yeah yeah, nothing happened hahaa.
1658. RickWPB
I read where someone posted...

"THE 06Z/12Z GFS AND 12Z CANADIAN SOLUTIONS HAD TO BE THROWN OUT BY DEFAULT"

...so went looking for it. This was in the 'extended forecast' discussion. Here's a quote:

EXTENDED FORECAST DISCUSSION
NWS HYDROMETEOROLOGICAL PREDICTION CENTER COLLEGE PARK MD
229 PM EDT FRI AUG 24 2012

VALID 12Z MON AUG 27 2012 - 12Z FRI AUG 31 2012

...ISAAC EXPECTED TO MOVE INTO THE MID-SOUTH BY NEXT FRIDAY...

THE WESTERLIES ACROSS THE NORTHERN PACIFIC ARE NORTH OF WHAT IS
NORMAL FOR LATE AUGUST. THIS FORCES ENERGY TO POOL DOWNSTREAM,
ACROSS THE PACIFIC NORTHWEST, WITH DOWNSTREAM TROUGHING EXPECTED
ACROSS THE NORTHEAST AND A WARM CORE RIDGE EXPECTED TO WAVER IN
POSITION AND STRENGTH BETWEEN THE CENTRAL ROCKIES AND CENTRAL
PLAINS. THE DETERMINISTIC AND ENSEMBLE MEAN GUIDANCE IS IN GOOD
AGREEMENT ON THESE GENERAL IDEAS. THE MODEL CHOICE THIS PERIOD
WAS PARTIALLY CONSTRAINED BY THE LATEST NATIONAL HURRICANE CENTER
(NHC) FORECAST FOR ISAAC, WHICH RESEMBLED THE 12Z UKMET THROUGH
THURSDAY MORNING. A 00Z GFS/00Z ECMWF COMPROMISE WAS USED
THEREAFTER, WITH INPUT RECEIVED FROM NHC REGARDING TROPICAL
SYSTEMS AT 17Z. THE 06Z/12Z GFS AND 12Z CANADIAN SOLUTIONS HAD TO
BE THROWN OUT BY DEFAULT. THIS LED TO REASONABLE CONTINUITY WITH
THE MID-MORNING PRESSURES.

...snip
Quoting TomTaylor:
Here's my latest track forecast. Similar to the one I made three days ago for the short term. Midpoints aren't drawn, but I still think South Florida or just west of there over the Keys. From there I expect it to enter the Gulf and then make landfall around the central Florida Panhandle. The track consensus is a little west of there at the moment, although I am pretty inline with the consensus. Anyway, I like the strong consistency among the GFS ensembles and the track shown by the 12z UKMET (especially the curve back to the north, rather than a due NW heading). Canadian likely too far east, while the ECMWF is likely too far west, and also don't think Isaac will continue on that NW heading for so long.

I suppose if I put a midline down the track it would look something like this. Obviously, there is a greater model spread to the west of the model consensus, so I have greater uncertainty on that side. Also keep in mind my track forecast over and around Cuba is pretty uncertain because land interaction and mountains can do some tricky things. I'd pay more attention to the passage south of Florida and then the position of the panhandle landfall.

Quoting jeffs713:

You ***-caster!
Take out the "you" and you get to have fun with hypocatastasis.
1661. GoWVU
I am trying to digest all of the chatter on this blog and watch the weater channel. So it looks like the East Coast/South Carolina should get some rain and not really worry about the real nasty stuff?
Quoting jrweatherman:
There is one thing for sure about Isaac. It is NOT going WEST! 305 degree heading is not West.


It is definitely moving NW now..
Quoting nrtiwlnvragn:


Don't know about considerable, they want to avoid the "windshield wiper" affect. I would think a move eastward, at least for South Florida will occur.


I think so too.
Quoting jrweatherman:
There is one thing for sure about Isaac. It is NOT going WEST! 305 degree heading is not West.

True, but 305 has more westward movement than north movement!
nice TWC video where Brian Norcross and Knabb talk inside the NHC Hurricane Hurricane Operations room
check it out here!!!
Quoting Grothar:

You'd think they could have smoothed that track line out; cyclones don't make 90o turns.
Latest Euro Ensembles (12z) at the Gulf landfall (120hrs).

Quoting CaicosRetiredSailor:


not really....

There is a lot more American money in the Caymans....

; )


that is true but how much of it belongs to us a lot less than an county would have

people just put there money down here and sometimes even we don't know about it

but no I think he ment by Hurricanes yes Grad Cayman is like in the top 5 to get hit by hurricanes (a few times we were ranked as #1) and that is also why quite a bit of storm they and we say coming to Cayman and a good amount of them do end up here

Quoting hulakai:
Hey WKC, those folks are just pokin ya in the ribs. Just laugh (like levi) and they will go away. Keep watchin and expressin yer opinion and you'll learn as ya go along.

I'm 60 and been watchin fer a long time and I still learn something in here every day!

Could be one day, like doc and NHC folks will value your opinion over their own.

Meanwhile, wind is freshening here in Broward from NE



pokin' rib is one thing but constantly pestering me and name calling and total disrespect is another

here too moderate NE winds

Quoting CybrTeddy:
The most significant thing about the 18z model run suite (for me) was the fact that the model consensus now is now the TVCA is, like we mentioned, only showing Isaac briefly making landfall with Cuba instead of traversing half the length of the island as the NHC has it doing. The TVCA for those who don't know much about the models, is the mean or average of all the model runs. You will often find that the NHC follows usually pretty close to the TVCA.


last I recalled it was the TVCN that NHC follows
img src="http://www.cabaretecool.com:8080/cam_1.jpg?un iq=0.25012637581676245Caribbean getting choppy in the D.R.
1670. Seastep
Quoting MiamiHurricanes09:
NHC losing their marbles if there isn't a considerble eastward shift in the forecast cone.


I don't think it would be considerable.

A nudge works and is probably what they'll do.
Quoting Joshfsu123:



now that's pretty awesome.


Hope the duct tape holds up for a week or two.
1672. CJ5
Quoting ProgressivePulse:
Isaac doesn't want to go over those mountains unless he has to. Path of least resistance is through the passage. Interested to see the motion once he gets there.


Correct. He will begin to slow down, then at the right time start a zig zag motion through the Windward Passage and out into the Atlanatic. That is what I would do If I were him.
Quoting jrweatherman:
There is one thing for sure about Isaac. It is NOT going WEST! 305 degree heading is not West.


Thanks for making that one clear - not. I think we all know it is heading WNW to NW. lol
Quoting ProgressivePulse:
Isaac doesn't want to go over those mountains unless he has to. Path of least resistance is through the passage. Interested to see the motion once he gets there.
These systems sometimes have a mind of their own and can create their own mini-environments around a larger environment. Also in terms of landmass the friction usually draws them in.
Quoting Bluestorm5:


lots of white in there
Quoting StormTracker2K:


Miami what is your thinking of the models taking this to southern FL while the NHC is much further south than the guidance? What is the feeling there in MIA? Is the media properly informing people are are they being conservative as the mets in Orlando are?



The news media in MIA has been saying that it "can't hurt" to be prepared and, as they show empty grocery store shelves formerly filled with bottled water, say that it is better to have the water than not just because it is hurricane season. They gently advise us to buy supplies but nothing more than that. They do not say they are being conservative- they say to wait another day or so because what will happen after the storm interacts with Cuba will tell us a lot. They did say we ought to think about filling prescriptions and that if someone has to call their doctor for a refill, they should do it now while there is that extra day or two to play with. Also said to stock up on pet food. All good suggestions for anyone on a vulnerable coast anytime during the season.
Quoting hurricanejunky:
None of these models go any further west then the FL/AL border. Not sure why the cone is that far west now...



It's because the EURO is the top ranked model and it is still the farthest west.
1678. Grothar
Quoting Levi32:
Holy cow! GOES-14 brought out of storage and running 1-min data until October, currently focused on Isaac!

1-min super rapid scan visible loop


Hey, Levi, with this "unexpected" :) shift. Would you say there is a possibility this could be a much stronger system if it approached the Bahamas and Florida? I know you don't like to guess.
Hey Levi........Your Tropical Tidbits was excellent as usual. Thank You.
TWC Mike Seidel is doing remotes from Cuba...That's a first. Very cool IMO.
Quoting RTSplayer:


Because about half of those models are crap anyway, and the most reliable model, the Euro, is not on that graphic (for legal reasons,) and it takes the storm much farther west.


Moreover, the consensus output of any one model is not set in stone, that is just the line representing the highest probability calculated by that model's members.

Even the GFS is not one center line. It's lots of members that are all over, though on this particular run the GFS members are closer to it's own consensus than on the two previous runs, still on the previous runs even the GFS had members going far to the west, even outside the cone.



Considering they claim to be using a "ECMWF compromise", I assume they mean a little east of the ECMWF, I wouldn't think New Orleans would be in the cone. A little too far west IMHO. Not trying to claim I know more than the NHC, just making some observations in hopes someone might be able to clarify. Not sure that has happened yet. Thanks anyways though.
Quoting jrweatherman:
There is one thing for sure about Isaac. It is NOT going WEST! 305 degree heading is not West.


Where is that west compass when you need it?

BTW based on the distance line projection I did on google earth, Isaac is moving at 16 mph.
there is no eye yet...........so why keep saying there is one.
1684. guygee
Quoting ncstorm:

Floyd..was supposed to hit florida..
No it was not, except in Guv Jebby's mind.
Quoting GoWVU:
I am trying to digest all of the chatter on this blog and watch the weater channel. So it looks like the East Coast/South Carolina should get some rain and not really worry about the real nasty stuff?


well...it's likely to be pretty nasty for us....but not Godawful...
Torrential tropical rain here today in sfl.
1687. emcf30
Quoting Levi32:
Holy cow! GOES-14 brought out of storage and running 1-min data until October, currently focused on Isaac!

1-min super rapid scan visible loop


That is a very cool tool. A friend of mine text me a bit ago with that link. Loading the 300 frame animation now. Thanks for sharing
1688. Grothar
I expect a significant shift to the East with all the models at the next advisory.
1689. GoWVU
Quoting presslord:


well...it's likely to be pretty nasty for us....but not Godawful...


Press thanks for taking the time to answer. I am supposed to go on a trip leaving Wed.
Quoting Levi32:
Holy cow! GOES-14 brought out of storage and running 1-min data until October, currently focused on Isaac!

1-min super rapid scan visible loop


Very nice find! Thanks Levi
Quoting wunderkidcayman:


that is true but how much of it belongs to us a lot less than an county would have

people just put there money down here and sometimes even we don't know about it

but no I think he ment by Hurricanes yes Grad Cayman is like in the top 5 to get hit by hurricanes (a few times we were ranked as #1) and that is also why quite a bit of storm they and we say coming to Cayman and a good amount of them do end up here



pokin' rib is one thing but constantly pestering me and name calling and total disrespect is another

here too moderate NE winds



last I recalled it was the TVCN that NHC follows


You weather geeks have more acronyms than we had in the army. :)
Isaac on the coast of DR


Quoting GoWVU:


Press thanks for taking the time to answer. I am supposed to go on a trip leaving Wed.


that'd be a good day to get outta town
1694. Grothar
Quoting redwagon:

You'd think they could have smoothed that track line out; cyclones don't make 90o turns.


Oh, sometimes they do.
Quoting nrtiwlnvragn:


Don't know about considerable, they want to avoid the "windshield wiper" affect. I would think a move eastward, at least for South Florida will occur.
At this point, a 75 mile shift is "considerable" in my eyes hahaa. Your point is valid, but there's a difference between avoiding the "windshield wiper" effect and giving people a false sense of complacancy.
1696. LargoFl
I would imagine, they would order evacs in all the beachside communities if he comes up the coast huh.....Pinellas County has five evacuation zones:
•A (Red) - Potential surge is 4 to 8 feet.
•B (Orange) - Potential surge is 8 to 14 feet.
•C (Yellow) - Potential surge is 14 to 19 feet.
•D (Green) - Potential surge is 19 to 26 feet.
•E (Purple) - Potential surge is 26 to 29 feet.

If you live in any of the beach communities (along Gulf Boulevard or across the bridges), you are in zone A.
Latest on Recon Info:
994 MB central Pressure
16.9N 71.7W
65 Mph Surface Winds
80 Mph Flight Level Winds
and the east trend begins, climatology wants this to ride the east coast of FL, something to still be considered, IMO
1699. HarryMc
Quoting emcf30:


That is a very cool tool. A friend of mine text me a bit ago with that link. Loading the 300 frame animation now. Thanks for sharing


I agree. That has to be the neatest loop I've seen in a long time
Quoting Jedkins01:
The NHC isn't going to swing it's forecast track way east just because the GFS has shifted well east. They are discounting it because they plan to wait and see how additional runs from the model turn out, as well as to see how runs from the other models turn out. The overall consensus has shifted a little further to the east this afternoon, so I expect the NHC to adjust it a bit more east at the 5 PM advisory or maybe by tonight if the trend continues. They do that for a reason, because if they flip flopped their track back and forth all the time that makes them unrealistic and unreliable. But of course contentious individuals never stop to think about that.
We're definitely going to get a lot of weather from this track Jed... should be just the right amount of excitement without causing a lot of damage. The convention will be screwed though which I am ok with. I was getting upset about their preventing protesting bureaucracy anyway
1701. FOREX
Quoting hurricanejunky:


Considering they claim to be using a "ECMWF compromise", I assume they mean a little east of the ECMWF, I wouldn't think New Orleans would be in the cone. A little too far west IMHO. Not trying to claim I know more than the NHC, just making some observations in hopes someone might be able to clarify. Not sure that has happened yet. Thanks anyways though.


I'm trying to look at it this way. Le Bron James is the EURO and Dwayne Wade is the GFS. Both are awesome players. Miami makes the finals and decides that Wade is good enough and they let LeBron sit and rest a few games. That would be stupid. Time will tell I guess.
Look at all the convection gathering north of Cuba a sure sign that is where Issac is heading or may even get pulled into at some point over the next 36 hours. Watch this area north of eastern Cuba for Issac to end up there over the next day or so.


1703. LargoFl
Quoting stormchaser19:
Isaac on the coast of DR


boy we are going to see alot of that here
If Isaac stays on it's current heading it's going to spend very little time over land...
Quoting RetiredPWB:
TWC Mike Seidel is doing remotes from Cuba...That's a first. Very cool IMO.
I agree! If I could go there too... I'm so damn close!
Looking at the satellite presentation this afternoon, Isaac doesn't look as organized as few hours ago??, any comments on this observation?.
1707. barbamz
Quoting weatherconch:
Link

Heres a cool view if you have a big monitor.


True. The most breathtaking one.
I'm not sure you guys are getting the whole thing Re: HPC

THE MODEL CHOICE THIS PERIOD WAS PARTIALLY CONSTRAINED BY THE LATEST NATIONAL HURRICANE CENTER (NHC) FORECAST FOR ISAAC, WHICH RESEMBLED THE 12Z UKMET THROUGH THURSDAY MORNING. A 00Z GFS/00Z ECMWF COMPROMISE WAS USED THEREAFTER, WITH INPUT RECEIVED FROM NHC REGARDING TROPICAL SYSTEMS AT 17Z. THE 06Z/12Z GFS AND 12Z CANADIAN SOLUTIONS HAD TO BE THROWN OUT BY DEFAULT. THIS LED TO REASONABLE CONTINUITY WITH THE MID-MORNING PRESSURES.

The last NHC track is similar to the UKMET, and for consistency purposes they had to show a track similar to the UKMET. Obviously the GFS and CMC are further east and could not be considered when it came to fronts and pressure.

At least thats what I got out of it.
Quoting cutlerbay32:


The news media in MIA has been saying that it "can't hurt" to be prepared and, as they show empty grocery store shelves formerly filled with bottled water, say that it is better to have the water than not just because it is hurricane season. They gently advise us to buy supplies but nothing more than that. They do not say they are being conservative- they say to wait another day or so because what will happen after the storm interacts with Cuba will tell us a lot. They did say we ought to think about filling prescriptions and that if someone has to call their doctor for a refill, they should do it now while there is that extra day or two to play with. Also said to stock up on pet food. All good suggestions for anyone on a vulnerable coast anytime during the season.


that is the perfect thing to say.. we don't want panic but we want people to be prepared.
Thanks for posting that here.

I am in Broward County.
Quoting Grothar:
I expect a significant shift to the East with all the models at the next advisory.


I agree but they seldom do significant shifts. I would expect a slight shift to the east with the disclaimer that additional eastward shifts might be necessary.
waiting to hear what Max Mayfield say at 5pm on Channel 10 news. He's my weather god! I do as Max says!
1712. LargoFl
.....7-day for tampa bay..they keep changing it
Quoting trHUrrIXC5MMX:
nice TWC video where Brian Norcross and Knabb talk inside the NHC Hurricane Hurricane Operations room
check it out here!!!


My friend was there earlier this year during 92L:

Isaac the last 72 hours... really cool.



Link
1715. guygee
Quoting Levi32:
Holy cow! GOES-14 brought out of storage and running 1-min data until October, currently focused on Isaac!
Very cool, good catch, thanks. They seem to have a glitch in the cartographic projection but that is still an awesome view.
1716. WxLogic
Quoting Grothar:
I expect a significant shift to the East with all the models at the next advisory.


Likewise... I expect that for the first 48 hours for the track to closer to the current consensus up to S FL and then a track closer to FL W coast. In which a bending would be noticed W of Tampa and finally ending in the KTLH area.

A guess we'll see in a couple minutes. Also Isaac still moving NW.
1717. Grothar
You guys know the drill.

Quoting charlottefl:
If Isaac stays on it's current heading it's going to spend very little time over land...


and .......??? (I know what is gonna happen.
1719. LargoFl
Just got my first chance to look at Isaac in the last few hours. What the heck happened to him? He looks just horrible. Is he as disorganized as satellite would suggest, or is he better than he looks at the moment?
Quoting WxGeekVA:


My friend was there earlier this year during 92L:



I wish I can visit NHC one day...
Quoting WPBHurricane05:
I'm not sure you guys are getting the whole thing Re: HPC

THE MODEL CHOICE THIS PERIOD WAS PARTIALLY CONSTRAINED BY THE LATEST NATIONAL HURRICANE CENTER (NHC) FORECAST FOR ISAAC, WHICH RESEMBLED THE 12Z UKMET THROUGH THURSDAY MORNING. A 00Z GFS/00Z ECMWF COMPROMISE WAS USED THEREAFTER, WITH INPUT RECEIVED FROM NHC REGARDING TROPICAL SYSTEMS AT 17Z. THE 06Z/12Z GFS AND 12Z CANADIAN SOLUTIONS HAD TO BE THROWN OUT BY DEFAULT. THIS LED TO REASONABLE CONTINUITY WITH THE MID-MORNING PRESSURES.

The last NHC track is similar to the UKMET, and for consistency purposes they had to show a track similar to the UKMET. Obviously the GFS and CMC are further east and could not be considered when it came to fronts and pressure.

At least thats what I got out of it.


Me too.
KeyWestwx,  here is the offical link to the European model animated




Quoting leelee75k:
waiting to hear what Max Mayfield say at 5pm on Channel 10 news. He's my weather god! I do as Max says!


be sure and let us know what he says, i will be at work until 7pm
Really cool pronounced trochoidal oscillation with Bolaven in the WPAC.

Whats up WU, Isaac looking grim for SE Florida than yesterday. The Euro is not having a good handle on the storm because its lack of a dominant LLC and little vertical stacking. I also noticing dry air falling apart as the outflow is just too strong to disrupt it. Thus a eastern shift is likely in the next advisory. Convection was concentrated to the LLC's SW however those bug thunderstorms have wane and new convection is firing right over the COC. MLC is slightly displace and by tonight it should be vertically stacked which could put it over Cat.1 status. It will go over a thin strip of Hait and emerge over water which could help it become a cane if it didnt make it tonight. Before going over Cuba Saturday evening. Emerging on Sunday where it should slow down a bit (10-15mph) giving it the almost the whole Bahamas to strengthen. Possibly rapidly strengthen
into a Major Cane coming to Southern Florida. Always Stay tuned as yesterday SE Florida was becoming less likely and know its more likely and could be way stronger than a TS. For all who lives in S. Florida start preparing tonight and make precautions Saturday I notice some south Florida isnt taking it serious which is bothering me right now. LOL its the 20 year anniversary of Hurricane Andrew man talk about IRONY.
1727. Grothar
Quoting WxLogic:


Likewise... I expect that for the first 48 hours for the track to closer to the current consensus up to S FL and then a track closer to FL W coast. In which a bending would be noticed W of Tampa and finally ending in the KTLH area.

A guess we'll see in a couple minutes. Also Isaac still moving NW.


The shift may be very significant as well as intensity. Just saying. I really have no way of knowing for sure.
Quoting WxLogic:


Likewise... I expect that for the first 48 hours for the track to closer to the current consensus up to S FL and then a track closer to FL W coast. In which a bending would be noticed W of Tampa and finally ending in the KTLH area.

A guess we'll see in a couple minutes. Also Isaac still moving NW.


Look north of Cuba right now. Lots of action building there almost like it's getting ready for Issac to move in. Very very interesting to say the least and I'm the only to comment on this over the last couple of days.

Quoting seflagamma:


that is the perfect thing to say.. we don't want panic but we want people to be prepared.
Thanks for posting that here.

I am in Broward County.


I always buy more wal-mart stock a few days before a predicated GOM, SE Coast landfall
Quoting leelee75k:
waiting to hear what Max Mayfield say at 5pm on Channel 10 news. He's my weather god! I do as Max says!


I do as no one says. Just Saying.
Looking at the recon info on Levi's website (which is awesome, by the way), it looks like Isaac still isn't perfectly stacked. His lowest MSLP is shifted slightly to the north of the flight-level center. The shift isn't much to speak of, so he can still strengthen - it is just an interesting item of note.
Quoting LargoFl:
boy we are going to see alot of that here
Quoting LargoFl:
boy we are going to see alot of that here


Look at
Quoting LargoFl:
boy we are going to see alot of that here


Look at the satellite on post 1702. Put Issac anywhere off our coast and look what would be on top of us.
Quoting Grothar:
You guys know the drill.



funny! reminds of the that first blogging summer of 2005!
Quoting Grothar:
You guys know the drill.



Command R :)
1735. Grothar
Quoting WPBHurricane05:
I'm not sure you guys are getting the whole thing Re: HPC

THE MODEL CHOICE THIS PERIOD WAS PARTIALLY CONSTRAINED BY THE LATEST NATIONAL HURRICANE CENTER (NHC) FORECAST FOR ISAAC, WHICH RESEMBLED THE 12Z UKMET THROUGH THURSDAY MORNING. A 00Z GFS/00Z ECMWF COMPROMISE WAS USED THEREAFTER, WITH INPUT RECEIVED FROM NHC REGARDING TROPICAL SYSTEMS AT 17Z. THE 06Z/12Z GFS AND 12Z CANADIAN SOLUTIONS HAD TO BE THROWN OUT BY DEFAULT. THIS LED TO REASONABLE CONTINUITY WITH THE MID-MORNING PRESSURES.

The last NHC track is similar to the UKMET, and for consistency purposes they had to show a track similar to the UKMET. Obviously the GFS and CMC are further east and could not be considered when it came to fronts and pressure.

At least thats what I got out of it.



That is a pretty good analysis
1736. LargoFl
1737. Grothar
Quoting seflagamma:


funny! reminds of the that first blogging summer of 2005!


I was amazed by you guys back then.
KeyWestwx,  here is the offical link to the European model animated.

http://www.ecmwf.int/products/forecasts/d/animate /catalog/products/forecasts/medium/deterministic/m sl_uv850_z500%21Wind%20850%20and%20mslp%2172%21Nor th%20America%21pop%21od%21oper%21public_plots%2120 05101800%21%21%21step/
305degrees heading is about exactly WNW, which is about a 1N to 2W ratio in movement, though it will be distorted somewhat by the curvature of the Earth.


Sine 35 = 0.57


So for every 1W it's 0.57N


So if it held it's present heading, it would cross 75W at about 18.4N...
Quoting Tribucanes:
Just got my first chance to look at Isaac in the last few hours. What the heck happened to him? He looks just horrible. Is he as disorganized as satellite would suggest, or is he better than he looks at the moment?


Not quite sure what you mean. This storm's central pressure has dropped 6 millibars today; it's finally set up a temperature differential within its core, as it's warmed substantially; and it's been wrapping convection around the center of its circulation. I've never seen it look as good as it does right now.
Quoting WPBHurricane05:
I'm not sure you guys are getting the whole thing Re: HPC

THE MODEL CHOICE THIS PERIOD WAS PARTIALLY CONSTRAINED BY THE LATEST NATIONAL HURRICANE CENTER (NHC) FORECAST FOR ISAAC, WHICH RESEMBLED THE 12Z UKMET THROUGH THURSDAY MORNING. A 00Z GFS/00Z ECMWF COMPROMISE WAS USED THEREAFTER, WITH INPUT RECEIVED FROM NHC REGARDING TROPICAL SYSTEMS AT 17Z. THE 06Z/12Z GFS AND 12Z CANADIAN SOLUTIONS HAD TO BE THROWN OUT BY DEFAULT. THIS LED TO REASONABLE CONTINUITY WITH THE MID-MORNING PRESSURES.

The last NHC track is similar to the UKMET, and for consistency purposes they had to show a track similar to the UKMET. Obviously the GFS and CMC are further east and could not be considered when it came to fronts and pressure.

At least thats what I got out of it.


In a nutshell it's preventing the quick shift in track. Now if the next cycle continues to show it, then it will be considered. I'll tip my hat to you now and bow if you show it again.
1742. Thrawst
Quoting StormTracker2K:


Look north of Cuba right now. Lots of action building there almost like it's getting ready for Issac to move in. Very very interesting to say the least and I'm the only to comment on this over the last couple of days.



I was thinking that too.. very good upper divergence in our area. Wait, lemme get this straight...

Has the expected track of Isaac gotten any closer to me (Nassau, Bahamas) ?
Quoting Grothar:


The shift may be very significant as well as intensity. Just saying. I really have no way of knowing for sure.
I agree, it's a bad/bad situation for south Florida. In order for the cyclone to come closer to the mainland, it has to also be more intense as well.
Interesting to note that the ECMWF has been right on everything up to this point. We will have to see if that continues.
wow next Tue. Aug 28th, will be the 7th Anniversary of the day I signed up here on WU!..
I was "lurking" a little while before I got the nerve to join in the fun.
Quoting Bluestorm5:
Isaac the last 72 hours... really cool.



Link


Very cool...thanks for sharing
Isaac is a bad boy...few miles of my house
Quick look at the dropsonde data from Gonzo indicates the ridge to the north is a little weaker than yesterday. 500mb heights 10-20 m lower.
Quoting Surferdude:
Welcome to Florida ...we have been expecting you.

I am jumping on the bandwagon(didn't think he would make it), Isaac is getting serious now. Will be Hurricane Isaac by 2am giving the current intensification...close to 994mb now and moving NW...

Levi's track seems very reasonable. Best dude we have on this blog.


I concur. I think it hits just west of Miami at a Cat 2
1750. guygee
Quoting oceanspringsMS:
You weather geeks have more acronyms than we had in the army. :)
A lot of acronyms but no cigar for you. No one beats the DoD for acronyms. On top of that when there is a big change (like firing Gen. Shinseki)there is always a whole new set of acronyms.
Quoting seflagamma:


funny! reminds of the that first blogging summer of 2005!
Me too lol, needed a little laugh right now :)
Quoting Grothar:
You guys know the drill.


Ive known the Drill ever since I learned what the f5 Button truly does. LOL
Tampa Bay is right in the center of the eye on the 12Z GFS. Aw hell just throw it out per NHC


CMC precip accum.

1754. LargoFl
....................look how THis has changed since 11 am
Even the NWS floater satellite is starting to show a well defined location of central rotation (visible spectrum).

http://www.ssd.noaa.gov/PS/TROP/floaters/09L/flas h-vis-long.html
1756. Grothar
Quoting Tribucanes:
Just got my first chance to look at Isaac in the last few hours. What the heck happened to him? He looks just horrible. Is he as disorganized as satellite would suggest, or is he better than he looks at the moment?


Oh, Trib, I thought you were talking about me for a minute.
Quoting oceanspringsMS:


I always buy more wal-mart stock a few days before a predicated GOM, SE Coast landfall

Home Depot or Lowe's might be a better bet.
Quoting jeffs713:
Looking at the recon info on Levi's website (which is awesome, by the way), it looks like Isaac still isn't perfectly stacked. His lowest MSLP is shifted slightly to the north of the flight-level center. The shift isn't much to speak of, so he can still strengthen - it is just an interesting item of note.


Which reminds me...Is Stephanie Abrams still in Key West?
1759. WxLogic
Quoting stormchaser19:
Isaac is a bad boy...few miles of my house


DR doesn't have sink holes (at least that I've heard of) but sure looks like the ground decided to collapse in that crossing.
1760. Grothar
Quoting HurricaneDean07:

Ive known the Drill ever since I learned what the f5 Button truly does. LOL


I think TropicalAnalyst taught me about that button. :)
Quoting caribnewsman:

Not to the same degree, but it does identify someone as a tourist/foreigner.

The point is, Isaac could very well pass closely to two of the three Cayman Islands just as easily as it could pass very closely to Miami.


And I live on the Northern most of the 3 and am by no means convinced that we are "out of the woods and in the clear".
Thankfully, at this time the Wind fields in Southern quadrants seem much smaller - BUT - the way Isaac has flobbled around, who can tell?
Quoting leelee75k:
waiting to hear what Max Mayfield say at 5pm on Channel 10 news. He's my weather god! I do as Max says!
leelee... I am in Palm Beach county. Wondering if I can get it here..
JeffMasters has created a new entry.
Quoting nrtiwlnvragn:
Quick look at the dropsonde data from Gonzo indicates the ridge to the north is a little weaker than yesterday. 500mb heights 10-20 m lower.


Interesting.

1765. wpb
will they post any watches for keys sfla at 5pm or wait until 11pm.they like to advise before late hours??????????
Quoting FOREX:


I'm trying to look at it this way. Le Bron James is the EURO and Dwayne Wade is the GFS. Both are awesome players. Miami makes the finals and decides that Wade is good enough and they let LeBron sit and rest a few games. That would be stupid. Time will tell I guess.


I'm really glad you used that analogy because I'm from Miami so naturally my favorite team is the Heat! Not sure why they're so heavily weighted toward the GFS but since they're usually spot on with track I guess I'll keep my second guessing to myself. I can't help but think of the Debby debacle. That is very out of character for the NHC but they are under new leadership so we'll see...
Quoting TropicalAnalystwx13:
Interesting to note that the ECMWF has been right on everything up to this point. We will have to see if that continues.
Not realllyyyy.
Quoting jeffs713:

Home Depot or Lowe's might be a better bet.

Better PM on bottled water and canned tuna
Quoting jeffs713:

Home Depot or Lowe's might be a better bet.


a good place to go for storm supplies, that a lot of people do not think of.. Dollar General. When Katrina was breathing down my neck and WM, LOWES, HD etc were sold out of everything, Dollar General had everything I needed.
Quoting Grothar:



That is a pretty good analysis


I agree. And for the record I posted the whole thing to begin with. I'm such a trouble maker.
1771. HrDelta
Quoting LargoFl:
all of a sudden..sand bags are like GOLD you have to show ID to get them?..............PINELLAS COUNTY

Sandbags will be available Saturday and Sunday from 8 a.m. to 5 p.m., weather permitting. Residents must have identification that verifies they are residents of St. Petersburg. Twenty bags per vehicle allowed.

Northeast Park, 875 62nd Avenue NE at the Cardinal Drive entrance to Mangrove Bay Course
Frank W. Pierce Recreation Center, 2000 Seventh St. St, enter from 22nd Ave. S., east side of Seventh Street


That is the stupidest thing I have ever heard.

To be honest, I have noticed that, the lowest levels of government (hello Municipalities!) tend to be the ones that do the mind-bendingly stupid stuff.
Quoting Bluestorm5:
Isaac the last 72 hours... really cool.



Link
Really cool. Thanks for posting.
Quoting presslord:


Which reminds me...Is Stephanie Abrams still in Key West?
She is...For the duration
Quoting presslord:


Which reminds me...Is Stephanie Abrams still in Key West?

She is on google images, tho.
Quoting seflagamma:
wow next wed. Aug 28th, will be the 7th Anniversary of the day I signed up here on WU!..
I was "lurking" a little while before I got the nerve to join in the fun.


I got you beat on joining, but certainly not on number of posts.

Just saw Joe Bastardi on Fox Business. Quite the fear-monger. He even said it Isaac might 'explode' and become a Cat 3. He also needs to learn to say Biloxi-- not Ba-Locks-ee
Quoting CloudGatherer:


Not quite sure what you mean. This storm's central pressure has dropped 6 millibars today; it's finally set up a temperature differential within its core, as it's warmed substantially; and it's been wrapping convection around the center of its circulation. I've never seen it look as good as it does right now.
Thanks for the reply. Statistically and conditionally he's the best he's been, just his presentation on satellite looks disheveled to my untrained eye. Thanks much for clarifying
Another thing of note the HPC was using the NAM for it's forecast which is the worst model of them all. Geesh!


Picture 1 hour ago from my cousin in Santo Domingo, DR. You can see a little flooding in the distant sidewalk (DR floods easily due to poor drainage).
Very cool:

1781. HrDelta
Quoting ringeaux:


I got you beat on joining, but certainly not on number of posts.

Just saw Joe Bastardi on Fox Business. Quite the fear-monger. He even said it Isaac might 'explode' and become a Cat 3. He also needs to learn to say Biloxi-- not Ba-Locks-ee


His little outfit was responsible for many deaths in regards to the bungling of the response to Katrina, and the Rita Hysteria.

At least 127 people died because of Accuweather's malfeasance.
levi are you here?
1783. kwgirl
Quoting Hurricanes305:
Whats up WU, Isaac looking grim for SE Florida than yesterday. The Euro is not having a good handle on the storm because its lack of a dominant LLC and little vertical stacking. I also noticing dry air falling apart as the outflow is just too strong to disrupt it. Thus a eastern shift is likely in the next advisory. Convection was concentrated to the LLC's SW however those bug thunderstorms have wane and new convection is firing right over the COC. MLC is slightly displace and by tonight it should be vertically stacked which could put it over Cat.1 status. It will go over a thin strip of Hait and emerge over water which could help it become a cane if it didnt make it tonight. Before going over Cuba Saturday evening. Emerging on Sunday where it should slow down a bit (10-15mph) giving it the almost the whole Bahamas to strengthen. Possibly rapidly strengthen
into a Major Cane coming to Southern Florida. Always Stay tuned as yesterday SE Florida was becoming less likely and know its more likely and could be way stronger than a TS. For all who lives in S. Florida start preparing tonight and make precautions Saturday I notice some south Florida isnt taking it serious which is bothering me right now. LOL its the 20 year anniversary of Hurricane Andrew man talk about IRONY.
You can say that again. If it starts heading for the mainland, there will be no evacuation for the Keys no matter what anyone says. There will be gridlock on all roads leading out of S. Fla.
Quoting presslord:


Which reminds me...Is Stephanie Abrams still in Key West?


You are bad... yes sire you are bad!!! ROFL!!
Quoting Levi32:
Holy cow! GOES-14 brought out of storage and running 1-min data until October, currently focused on Isaac!

1-min super rapid scan visible loop
Awesome. i love it!
Quoting HoustonTxGal:


a good place to go for storm supplies, that a lot of people do not think of.. Dollar General. When Katrina was breathing down my neck and WM, LOWES, HD etc were sold out of everything, Dollar General had everything I needed.


That is a good suggestion. Every small town in the South has one. I filled up the cars today and put another 25 gals. in cans. Don't think we are going to get hit in MS, but I do know the price of gas will jump no matter where landfall is.
Circulation has finally started building convection in the western side of the storm. Hold on to your hats guys....

Here is a cool video link that shows the importance of vertical garage door bracing. Garage door failure is one of the top reasons for major damage in hurricanes.

CLICK HERE TO WATCH THE VIDEO
New blog folks.
Watching closely here
Go to the new blog.
Quoting WunderAlertBot:
JeffMasters has created a new entry.


Dang…I miss the old days when 500 people would scream NEW BLOG!!!
1793. o22sail
Quoting seflagamma:


funny! reminds of the that first blogging summer of 2005!

Yup. I see's it.
I've been gone most of the day.. Has something drastically changed in Isaac's track? Is something going to pull him east or has his winds gotten faster. I know someone said if his winds where to get to hurricane strength the he could be pulled north.

TIA,
Sheri
Look at how Typhoon Bolaven's center is bouncing and wobbling all over the place. prime example of how sometimes it is hard to know where the track of these storms will end up. it is like a spinning wobbling top could end up 300 miles to the north or south of its projected path with that spin it has.


1796. icmoore
Quoting Grothar:
I expect a significant shift to the East with all the models at the next advisory.


You know i'm getting tired of you and your east, east, east :)
Quoting kwgirl:
You can say that again. If it starts heading for the mainland, there will be no evacuation for the Keys no matter what anyone says. There will be gridlock on all roads leading out of S. Fla.


WOW!!! Look at the Radar for S. Floridians Im watching channel 7 news at 4pm they are saying there is a severe thunderstorm warning for southern Dade county looks like Isaac is pumping up moisture to s. florida. Environment looks moist around the storm. Very SCARY setup. I'm waiting on the 5pm forecast to put up Shutters.
Who is the stormchaser dude who had the live feed during Beryl and I think Irene? from last year. He's a funny guy! Hope he is here for Isaac,should he decide to have landfall in Florida.
As long as Isaac continues to suck in the dry air like it's still doing, this storm is not gonna be a big deal anywhere.
1800. Thrawst
Quoting gustavcane:
Look at how Typhoon Bolaven's center is bouncing and wobbling all over the place. prime example of how sometimes it is hard to know where the track of these storms will end up. it is like a spinning wobbling top could end up 300 miles to the north or south of its projected path with that spin it has.




those wobbles are called Trochoidal oscillations. They only occur in intense hurricanes. Isaac is not an intense hurricane, and rather those wobbles in track are partly due to reformations, and just slight deviations in the track. :)
Quoting TheWeatherMan504:


You can't just look at one frame, Reed. You have to look at the evolution of the pattern. The Euro has the continental ridge bridging with the Bermuda high by 144 hours and that's why the Euro has the solution that it has.



Levi? Do you think the EURO is having issues with the High in the western gulf,like it did with the high NW of Debby?
New Blog, BTW.
I live in South Florida.... when should I consider putting up shutters? It's a pain in the butt!!
60 hrs.

Is that what it looks like in the last frames, or is Isaac just winking and saying you poor bastards?

http://rammb.cira.colostate.edu/templates/loop_di rectory.asp?data_folder=dev/lindsey/loops/goes14&i mage_width=1020&image_height=720&number_of_images_ to_display=50
Quoting Levi32:
Holy cow! GOES-14 brought out of storage and running 1-min data until October, currently focused on Isaac!

1-min super rapid scan visible loop


Looks like some big Thunderstorms/Hot Towers firing up around a elongated nw to se eye?
Quoting jrweatherman:
There is one thing for sure about Isaac. It is NOT going WEST! 305 degree heading is not West.


Yup,I had it going 302
Quoting StormTracker2K:


Look north of Cuba right now. Lots of action building there almost like it's getting ready for Issac to move in. Very very interesting to say the least and I'm the only to comment on this over the last couple of days.



What does that mean in english? :)
Quoting StormTracker2K:
Tampa Bay is right in the center of the eye on the 12Z GFS. Aw hell just throw it out per NHC


CMC precip accum.



didn't they throw the cmc out to?
Floridian's Hurricane Shutter Decision tree

Is a hurricane or tropical storm approaching ?

If no -- > go lie down in the hammock and have a beer
If yes ---> Is your home within the NHC cone of concern ?

If no ---> go lie down in the hammock and have a beer until it is
If yes ---> Mull over how energetic you feel and then go stand in front of shutters and stare for a while, you know you might need to do this

Is you city under a hurricane warning ?

If yes ---> put shutters up at least 5 hours before tropical storm winds arrive
If no ---> go lie down in the hammock and have another beer to contemplate the situation some more

Are there any models (excluding XTRAP) which indicate it will be a hurricane when it gets to your house ?

If yes ---> put shutters up at least 5 hours before tropical storm winds arrive
If no ---> go lie down in the hammock and have another beer to contemplate the situation some more

Have your neighbors started putting their shutters up ?
If yes ---> suck it up and get it over with, put the shutters up
If no ---> how sensitive are you to ridicule ?

and finally, given all the information available to you, how comfortable will you feel when the storm arrives if you have NOT put your shutters up ?


As always -- get your information from official sources and follow their directions.

Quoting southfla:
Floridian's Hurricane Shutter Decision tree

Is a hurricane or tropical storm approaching ?

If no -- > go lie down in the hammock and have a beer
If yes ---> Is your home within the NHC cone of concern ?

If no ---> go lie down in the hammock and have a beer until it is
If yes ---> Mull over how energetic you feel and then go stand in front of shutters and stare for a while, you know you might need to do this

Is you city under a hurricane warning ?

If yes ---> put shutters up at least 5 hours before tropical storm winds arrive
If no ---> go lie down in the hammock and have another beer to contemplate the situation some more

Are there any models (excluding XTRAP) which indicate it will be a hurricane when it gets to your house ?

If yes ---> put shutters up at least 5 hours before tropical storm winds arrive
If no ---> go lie down in the hammock and have another beer to contemplate the situation some more

Have your neighbors started putting their shutters up ?
If yes ---> suck it up and get it over with, put the shutters up
If no ---> how sensitive are you to ridicule ?

and finally, given all the information available to you, how comfortable will you feel when the storm arrives if you have NOT put your shutters up ?


As always -- get your information from official sources and follow their directions.



haha
Human nature vs hurricane expediency. That was awesome. :)