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Isaac approaching hurricane strength

By: Angela Fritz 9:14 PM GMT on August 27, 2012

Isaac is walking the line of hurricane status this afternoon after a hurricane hunter mission investigated the storm and found winds of 80+ mph with the SFMR instrument, which looks down at the surface from the plane and estimates what wind speeds are. This instrument has a notoriously rough time in doing so when there's heavy rain, and since the strongest winds were recorded coinciding with the strongest rain, you can imagine that this region of high wind speed could be suspect. The hurricane hunter mission is still in the storm, so I imagine they will issue a special update if needed. Currently the best estimate of wind speed within the storm is 70 mph. Isaac's pressure has been dropping today as well and is now 981 mb. Isaac is moving northwest at 12 mph--no change since this morning. Satellite loops show that Isaac remains large, though asymmetric, with most of the strong thunderstorm activity on the west and southwest side. Isaac's southeast side continues to struggle with dry air and wind shear, which could help to moderate Isaac's intensity as it approaches the coast.

An oil platform in the northern Gulf of Mexico is reporting sustained winds from the north-northeast at 40 mph this afternoon. A buoy west of Tampa, Florida is recording sustained winds around 30 mph, and platforms south of Louisiana are recording winds from 35-40 mph. The widespread heavy rain of yesterday has lightened up in Florida, but a strong line of thunderstorms in one of Isaac's outer bands is training northward along and offshore of the east coast of Florida, affecting everyone from Miami to Jacksonville.

This afternoon the AP reported that Isaac's death toll in Haiti jumped to 19, which puts Isaac's total death count at 21. It appears most of the deaths in Haiti were due to collapsing structures.


Figure 1. Satellite imagery of Tropical Storm Isaac around 3pm EDT on Monday.

Track forecast:
Models seem to be coming into better agreement today on where Isaac will make landfall, closing in on Louisiana and New Orleans as most likely landfall point. The ECMWF, HWRF, and UKMET all suggest New Orleans as the landfall location. The GFS is only slightly west of that. The GFDL is the farthest west, predicting landfall near the Louisiana-Texas border. Landfall timing remains Tuesday night. Beyond landfall, Isaac is expected to move north toward the Midwest through the rest of this week, however, models are showing that the system will likely slow down around landfall time, prolonging impacts like surge and inland flooding.

Intensity forecast:
The closer Isaac gets to landfall without having formed an eye, the better it is for intensity at landfall. Isaac has strengthened only modestly in the past 24 hours, and is still struggling with a less-than-conducive atmospheric environment. The HWRF remains on the high end of the intensity spectrum, suggesting Isaac will be a weak category 2 upon landfall. Other models suggest it will be a strong category 1, but the difference is splitting hairs. The National Hurricane Center's official forecast is for Isaac to continue strengthening over the next day, reaching category 2 at landfall.


Figure 2. Tide gauge data from St. Petersburg, Florida. The green line shows the storm surge. As Isaac's counterclockwise winds blew offshore this morning, water levels feel two feet at St. Petersburg. The winds switched to onshore this afternoon as the center of Isaac moved more to the northwest, bringing a storm surge of two feet to the city.

Storm surge observations from Isaac
This morning, as Isaac's counter-clockwise winds brought offshore winds to the Tampa/St. Petersburg area, ocean waters fell two feet along the coast. This afternoon, winds have shifted to blow onshore, and a two foot storm surge has been observed at Naples, Fort Meyers, and St. Petersburg on the west coast of Florida. Water levels have also begun to rise along the coast of Louisiana, with a storm surge of 1.5 feet already occurring at Shell Beach on the east side of New Orleans in Lake Borgne.

Angela and Jeff

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

3501. Levi32
They didn't upgrade Isaac. Unbelievable.
STILL not a hurricane

10:00 AM CDT Tue Aug 28
Location: 28.1°N 88.5°W
Moving: NW at 10 mph
Min pressure: 976 mb
Max sustained: 70 mph
3503. GetReal
Station KVOA
Federal Aviation Administration
Location: 29.229N 87.781W
Date: Tue, 28 Aug 2012 14:25:00 UTC
Winds: ESE (110°) at 60.0 kt gusting to 66.0 kt
Air Temperature: 80.6 F
Dew Point: 75.2 F
Visibility: 1.3 nmi
Quoting Felix2007:
How ironic that a storm that was once moving at 23mph has now crawled to the pace of a snail.


Two days ago GFS said this was going to happen. It was off on track by about 1 degree N though.


This is going to be pretty nasty once the eye passes to our west and starts dumping tens of inches of rain on NOLA and the Northshore and Livingston Parishes.

If it gets far enough west and floods the Amite basin too, then it could be very wide spread river flooding.


Another thing, since the Mississippi is so low from the early melt and the drought in the tributaries in the northern states and central plains states, the storm surge is going to screw up the fresh water environment.

there was already a salt water wedge moving upstream in the Mississippi just due to normal high tides, and that was over a week ago.

A really high storm surge with this track might push salt water all the way back up to Baton Rouge, or maybe at least half way there, since the river level is only like 4 feet at Baton Rouge last I heard...


Anyway, with this kind of forward speed we are going to see very wide spread 10 inch or greater totals, I think.
Quoting Patrap:


The forecast calls for

HAZARDS AFFECTING LAND
----------------------
STORM SURGE...THE COMBINATION OF A STORM SURGE AND THE TIDE WILL
CAUSE NORMALLY DRY AREAS NEAR THE COAST TO BE FLOODED BY RISING
WATERS. THE WATER COULD REACH THE FOLLOWING DEPTHS ABOVE GROUND IF
THE PEAK SURGE OCCURS AT THE TIME OF HIGH TIDE...

* SOUTHEAST LOUISIANA AND MISSISSIPPI...6 TO 12 FT
* ALABAMA...4 TO 8 FT
* SOUTH-CENTRAL LOUISIANA...3 TO 6 FT
* FLORIDA PANHANDLE...3 TO 6 FT
* FLORIDA WEST COAST INCLUDING APALACHEE BAY...1 TO 3 FT

everything I see for my area shows about 5 to 8....I am a ways from the lake. 1/2 mile. But I can look down the street and see it. Truck is full of gas if we gotta go . What time should the surge hit its peak here in the middle of the northshore?
darn you Isaac..become a wave crappy storm!!!
Quoting Charliesgirl:


oh well, anyone know how to post a photo? I put it to my photos on here.


I give up, how is not a hurricane. Flight level and surface winds support a hurricane.
...ISAAC STILL JUST BELOW HURRICANE STRENGTH AS IT CONTINUES
NORTHWESTWARD...


SUMMARY OF 1000 AM CDT...1500 UTC...INFORMATION
-----------------------------------------------
LOCATION...28.1N 88.5W
ABOUT 80 MI...125 KM SSE OF THE MOUTH OF THE MISSISSIPPI RIVER
ABOUT 165 MI...260 KM SE OF NEW ORLEANS LOUISIANA
MAXIMUM SUSTAINED WINDS...70 MPH...110 KM/H
PRESENT MOVEMENT...NW OR 310 DEGREES AT 10 MPH...17 KM/H
MINIMUM CENTRAL PRESSURE...976 MB...28.82 INCHES
Quoting Felix2007:

Watch Isaac still not become a hurricane.

What did I tell you? This thing will never become a hurricane... but if it doesn't then I think it must be upgraded in post-season analyis.
I have lost all confidence on the NHC... I'm done.
still no hurricane!!!!!
Just below...
11 am. Isaac still a ts. Twc is going to be upset
I don't care. Regardless of what they say, this thing is a hurricane with 80 MPH winds. Period. End of story.
I wonder if these trolls ever been in actual hurricane or any strong tropical storm.. probably not.. The ones that do the mocking really don't know what they r talking about.. I say if u r on here mocking then thats a new low for the ones r doing so.. Well I c more idiots come out everyday, know wonder this world is crazy..
haha @ TWC on air talent...

From the Louisiana Department of Transportation: LA 1 in both directions: Bridge closed at West 170th Street (near Golden Meadow). The bridge is closed. A Hurricane Warning is in effect. The Galliano Pontoon is closed on LA 1 (W. Main St.) at W. 170th St. for hurricane warning.


Still a TS, according to TWC......
I also think ACE is a little weird. It is based solely on wind speed so large storms like Isaac that have incredibly low pressures (for they're winds)still get the ACE of a TS
I think pressure could be included somehow
Quoting wayfaringstranger:


Reed, just let it roll off your back. I enjoy reading your posts. Your one of the few still on here from way back.

Too bad Destin J isnt back on here.



Isaac will be interesting in post analysis. Big mystery why he couldn't get stronger in ripe conditions in the GOM.

Yeah Destin Jeff was a really funny guy. He should be lifetime member in my book. Don´t know if he was banned or just got bored here.

Quoting Levi32:
They didn't upgrade Isaac. Unbelievable.


I had a feeling that they wouldn't.. I hear ya tho..
Click image for text and probabilities
New frame.

Wide spread plus 64kts winds and still has the minus 64kts too.

The left side of the eye wall may actually be stronger than the right side at the present time.
3525. junie1
SUPER TROPICAL STORM ISAAC
The discussion contradicts itself.

SFMR SURFACE WINDS HAVE ONLY BEEN AROUND 60-62 KT...
WHICH CORRELATES WELL WITH DROPSONDE BOUNDARY LAYER-DERIVED SURFACE
WINDS.
AS SUCH...THE INTENSITY OF ISAAC IS BEING MAINTAINED AT 60
KT...WHICH IS JUST BELOW HURRICANE STATUS.

Dropsondes say 80mph.
Quoting reedzone:
I have lost all confidence on the NHC... I'm done.


Lol
Quoting MysteryMeat:
STILL not a hurricane

10:00 AM CDT Tue Aug 28
Location: 28.1°N 88.5°W
Moving: NW at 10 mph
Min pressure: 976 mb
Max sustained: 70 mph


That's just stupid then.

They ignore the radar and their own dropsondes.

What's the point in the instruments if they aren't going to use their data?
i got a new name for Isaac


am calling Isaac the joker
3531. Patrap
Quoting presslord:
Cool live video here right now...Link


Big Duke NOLA 7..nice video..Hwy 90 at Biloxi..Beau Rivage as well. Nice stuff SJ.
Quoting osuwxguynew:
Radar shows inner eyewall/core died due to dry air entrainment. They may not upgrade after all...



look at post 3482,eye almost complete.
Quoting tkeith:
I think SJ looks a little smarter now Press...not any better, but a little smarter :)


lol. Hey tkeith! How are ya? Got the preps ready?
Quoting K8eCane:

if a-holes could fly, i swear sometimes this place would be an airport. never, ever underestimate a tropical system


I have 125 people on ignore now. lol

Anyway, GFS says eye wall of Isaac will be coming near me in SW LA.
3535. Levi32
Quoting reedzone:
I have lost all confidence on the NHC... I'm done.


Too far Reed. Too far. The NHC is the best we have. I don't understand why they have not upraded Isaac any more than you do, but they deserve and have earned the public's confidence. At least hurricane warnings have been out on the coastline for a long time now.
Lol. Wow, NHC. Surface winds of 80mph and flight level winds of 100mph aren't good enough???
Just a tropical storm folks, carry on as this will be a non event.....

lol
Isaac is still at TS status based on max sustained winds, which I believe is decieving.

The pressure, storm surge, rain, track, and forward progression once Isaac makes landfall will be comparable to a Cat 1/ 2.

Is there a chance that this hits the mouth of the Miss river?
Don't no folks. That might have been Isaac's last shot to get to the next grade.
Well that's great news!! Still just a TS!! YEA for us!! Get the popcorn this blog is about to go supersonic.
Don't worry there is a crow buffet somewhere around here.Well have a nice day :).
3543. Patrap


URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 591
NWS STORM PREDICTION CENTER NORMAN OK
945 AM CDT TUE AUG 28 2012

THE NWS STORM PREDICTION CENTER HAS ISSUED A
TORNADO WATCH FOR PORTIONS OF

SOUTHWEST ALABAMA
WESTERN FLORIDA PANHANDLE
SOUTHEAST LOUISIANA
FAR SOUTHEAST MISSISSIPPI
COASTAL WATERS

EFFECTIVE THIS TUESDAY MORNING AND EVENING FROM 945 AM UNTIL 700
PM CDT.

TORNADOES...HAIL TO 0.5 INCH IN DIAMETER...THUNDERSTORM WIND
GUSTS TO 70 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE
AREAS.

THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 55 STATUTE
MILES NORTH AND SOUTH OF A LINE FROM 15 MILES WEST OF NEW ORLEANS
LOUISIANA TO 20 MILES EAST OF PANAMA CITY FLORIDA. FOR A
COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE
UPDATE (WOUS64 KWNS WOU1).

REMEMBER...A TORNADO WATCH MEANS CONDITIONS ARE FAVORABLE FOR
TORNADOES AND SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH
AREA. PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR
THREATENING WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS
AND POSSIBLE WARNINGS.

DISCUSSION...A SLOW INCREASE IN CONVECTION HAS BEEN NOTED THIS
MORNING ON OUTER PERIPHERY OF ISAAC WHERE BREAKS IN THE CLOUDS ARE
SUPPORTING AIR MASS DESTABILIZATION. THIS TREND SHOULD CONTINUE
THROUGH THE REMAINDER OF THE MORNING AND THIS AFTERNOON WITH AN
INCREASED RISK FOR MINI SUPERCELLS AND AN ASSOCIATED TORNADO THREAT.

AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 0.5 INCH. EXTREME TURBULENCE AND SURFACE
WIND GUSTS TO 60 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO
450. MEAN STORM MOTION VECTOR 11040.


...MEAD
3544. ncstorm
two blobs on the east coast and tropical storm in the GOM..


What is going on in TWC studio....? Someone is not prepared!
Quoting sar2401:


Let's put this into perspective. Katrina had a maximum storm surge of 27.8 feet at Pass Christian MS. Average storm surge was in the order of 15 to 18 feet. The Grand Isle LA area had a storm surge of 16.2 feet. 6-12 feet is still a lot of water but it's not Katrina.

I don't under stand why everyone keeps wanting to compare to the worst natural disaster to hit our country. That is like saying the Iraq war wasn't bad let me put it into perspective and compare it to the Vietnam war. They are both bad and destructive just not as prolific but needs to have the proper attention paid to it just the same.
For the folks that live in this area

Houma, LA (70364) Weather Map

Link
Can't they just upgrade it to hurricane just so that people will take it seriously???
Quoting weatherh98:
storm pro, the lake is normal level.

this northeast windsare throuwing it to the south shore

it should gradually rise as the windshits

and eventually slosh it back up here witht he south wind


Thankf for the answers guys. My family and I are going to walk down there in a few...look for the bald tattooed guy in a black tank top lol
3550. Gearsts
Quoting Felix2007:

What did I tell you? This thing will never become a hurricane...
But it is a hurricane and is still deepening. Or it is the strongest TS i ever seen.
Quoting MississippiWx:
Lol. Wow, NHC. Surface winds of 80mph and flight level winds of 100mph aren't good enough???

One would think so, I would love to hear the NHC reasoning behind this.
Looks pretty. Beautiful-looking system on (HD-looking) visible loop. LINK

Isaac seemed to strengthen at the spot I mentioned at about 28n,88w. More thoughts when the fog clears! ;P
Quoting RTSplayer:


Two days ago GFS said this was going to happen. It was off on track by about 1 degree N though.


This is going to be pretty nasty once the eye passes to our west and starts dumping tens of inches of rain on NOLA and the Northshore and Livingston Parishes.

If it gets far enough west and floods the Amite basin too, then it could be very wide spread river flooding.


Another thing, since the Mississippi is so low from the early melt and the drought in the tributaries in the northern states and central plains states, the storm surge is going to screw up the fresh water environment.

there was already a salt water wedge moving upstream in the Mississippi just due to normal high tides, and that was over a week ago.

A really high storm surge with this track might push salt water all the way back up to Baton Rouge, or maybe at least half way there, since the river level is only like 4 feet at Baton Rouge last I heard...


Anyway, with this kind of forward speed we are going to see very wide spread 10 inch or greater totals, I think.


They were interviewing the Army Corp of Engineers yesterday on this very issue. They said there will be no problem, since the heavy rain will raise the Mississippi River and push the freshwater back south again.
Quoting Tazmanian:
i got a new name for Isaac


am calling Isaac the joker


Dry Air joker?

HH' on TWC pretty cool. :)
How are they going to ignore their own dropsonde.
Quoting Felix2007:
Can't they just upgrade it to hurricane just so that people will take it seriously???


that's not their job...I get your point...but that just ain't what they do...
Where is the "ignore user" button for the NHC??
3559. JeffM
Quoting farupnorth:



Isaac will be interesting in post analysis. Big mystery why he couldn't get stronger in ripe conditions in the GOM.

Yeah Destin Jeff was a really funny guy. He should be lifetime member in my book. Don´t know if he was banned or just got bored here.



Must be global warming. As they said, we're going to see more intense hurricanes...oh, wait.
3560. tkeith
Quoting hurricanehanna:


lol. Hey tkeith! How are ya? Got the preps ready?
Yes maam :) The folks at the NHC are making me look a liilte smarter for staying and riding this one out. I still think it has time and will be a Cat 1 hurricane. The folks in the low lying areas are definately gonna get wet feet. But if Issac dont spawn alot of tornaos we should be ok :)
Quoting sunlinepr:


Dry Air joker?


Dry Air Choker*
Not going to be good!!
3563. texasjo
I was hoping Isaac would jog more to the west and come up through Texas, and up into the DFW area. We need the rain! Hoping for the best for those affected by this guy though.
Quoting TropicalAnalystwx13:
How are they going to ignore their own dropsonde.


Oh no they hit the "Ignore User" button on their dropsonde!!
I would be furious if I was on the plane that got the 81mph winds... You proved beyond any doubt that the system is a hurricane and they totally blow off your reading?
Only 70mph, not bad, gonna be the rain and tidal influx that will cause the issues
Quoting TropicalAnalystwx13:
How are they going to ignore their own dropsonde.


reported for posting during school
Your telling me there are no 74 mph winds ANYWHERE in that storm? Don't buy it.
Quoting presslord:


that's not their job...I get your point...but that just ain't what they do...

I'm not saying that they should make every named storm a hurricane, but Isaac is pretty much one right now, don't see why they haven't upgraded him.
HH'S Said that's the first time they found winds that high. it will take time to work to the surface.
Quoting reedzone:


Me a troll?? Say that to the bloggers who enjoy my posts on here.. I have some haters but really a troll?? That's low man... I have a right to make predictions and maybe you haven't read my post one night saying I was WRONG in Isaac not busting the mid level ridge. I was WRONG in Isaac going up the East Coast. I was WRONG WRONG WRONG.. ok?


Don't always agree with you hardly ever and your avitar looks like a motorcycle cop (just joking), but you are not a troll you do not say stuff just to inflame people and you contribute greatly to the blog.
Quoting mynameispaul:


I have 125 people on ignore now. lol

Anyway, GFS says eye wall of Isaac will be coming near me in SW LA.


So you should be on post #21... And Isaac is still N of Cuba....
Quoting TropicalAnalystwx13:
How are they going to ignore their own dropsonde.

The NHC just used the ignore button on the dropsonde. We all don't know/get it.
Windy and light rain bands this morning; sun shining right now; TS warning discontinued east of Destin, so looks like my area dodged a bullet.

And I got a day off from work!

Stay safe, everyone to the west. Back to lurk mode unless things change dramatically.
Quoting JeffM:


Must be global warming. As they said, we're going to see more intense hurricanes...oh, wait.

Oh I know, right. How hilarious.
Wellington on 8/28/12


They just had live recon flight crew on while in storm. They reported that the winds at 8000 feet have not made way to surface. They could not find hurricane force winds at surface.
Quoting Thing342:
The discussion contradicts itself. SFMR SURFACE WINDS HAVE ONLY BEEN AROUND 60-62 KT...
WHICH CORRELATES WELL WITH DROPSONDE BOUNDARY LAYER-DERIVED SURFACE
WINDS. AS SUCH...THE INTENSITY OF ISAAC IS BEING MAINTAINED AT 60
KT...WHICH IS JUST BELOW HURRICANE STATUS.

Dropsondes say 80mph.


NHC: "Nooooo we want this to be the strongest tropical storm EVAR! Gotta break some kind of record on the 'I' storm, right!!"
3579. Patrap
Hey..I gotz a good idea.

Maybe we can replace the NFL Replacement Referee's with Banned wunderblogger's ?

POLL ?
3580. Michfan
How did they not upgrade it? I'm not gonna go bashing them but this is really baffling. Recon data clearly showed it was a hurricane. /facepalm.
Quoting weatherh98:


reported for posting during school

You're the one texting me! Lol.
Quoting TropicalAnalystwx13:
How are they going to ignore their own dropsonde.


They couldn't find any other instances of winds that fast. One reading could have been a localized gust or waterspout.
What happened to the 81mph surface winds from the dropsonde?
REPORTS FROM AIR FORCE AND NOAA HURRICANE HUNTER AIRCRAFT INDICATE
THE CENTRAL PRESSURE HAS DECREASED TO ABOUT 976 MB SINCE THE
PREVIOUS ADVISORY...BUT IT HAS LEVELED OFF OVER THE PAST FEW HOURS.
THE MAXIMUM 850 MB FLIGHT-LEVEL WIND OBSERVED HAS BEEN 89 KT...
WHICH EQUATES TO A SURFACE WIND OF ABOUT 71 KT. HOWEVER...
BIAS-ADJUSTED SFMR SURFACE WINDS HAVE ONLY BEEN AROUND 60-62 KT...
WHICH CORRELATES WELL WITH DROPSONDE BOUNDARY LAYER-DERIVED SURFACE
WINDS. AS SUCH...THE INTENSITY OF ISAAC IS BEING MAINTAINED AT 60
KT...WHICH IS JUST BELOW HURRICANE STATUS.
Live coverage on WDSU in New Orleans. The on-air weatherman just said that rain amounts should not amount to much, and this will be a minimal tropical storm. Not sure where he is getting that information. Gonna be a lot of flooding in New Orleans.

Quoting wxchaser97:

One would think so, I would love to hear the NHC reasoning behind this.

need that wind at the surface - that's where we all are...
Quoting tkeith:
Yes maam :) The folks at the NHC are making me look a liilte smarter for staying and riding this one out. I still think it has time and will be a Cat 1 hurricane. The folks in the low lying areas are definately gonna get wet feet. But if Issac dont spawn alot of tornaos we should be ok :)

I hear ya. Stay safe :)
3588. hydrus
I saw the long range models pick up on this over a week ago. Max Mayfield was concerned about this when Isaac was in the Atlantic.PRELIMINARY EXTENDED FORECAST DISCUSSION
NWS HYDROMETEOROLOGICAL PREDICTION CENTER COLLEGE PARK MD
958 AM EDT TUE AUG 28 2012

VALID 12Z SAT SEP 01 2012 - 12Z TUE SEP 04 2012

MOST MEDIUM RANGE GUIDANCE CONTINUES THE THEME OF LESS AMPLIFIED
FLOW OVER SRN CANADA AND THE NRN CONUS... THOUGH A SUBTLE HINT OF
TROFFING DEVELOPS OVER ERN NOAM BY AROUND DAY 7 NEXT TUE. NOT
SURPRISINGLY MEANINGFUL DIFFS REMAIN WITH INDIVIDUAL FEATURES
WITHIN THIS LOWER AMPLITUDE MEAN PATTERN. IN ADDITION SOLNS ARE
STILL NOT AS WELL CLUSTERED AS DESIRED WITH THE ULTIMATE PATH OF
ISAAC WHICH SHOULD WEAKEN TO TROPICAL DEPRESSION STATUS BY EARLY
DAY 3 FRI AND TRACK INTO THE MIDWEST DURING THE WEEKEND. CONSULT
LATEST NHC DISCUSSIONS/ADVISORIES FOR FURTHER INFO REGARDING ISAAC.

AS FOR INDIVIDUAL FEATURES... THE 00Z UKMET OR A COMPROMISE
BETWEEN THE GEFS MEAN/CANADIAN PROVIDES THE CLOSEST REPRESENTATION
OF THE 09Z NHC ADVISORY TRACK FOR ISAAC THRU DAY 4 SAT. THE UKMET
TRENDS SLOWER AFTER DAY 4. AFTER DAY 5 SUN EXPECT THE REMAINING
REFLECTION OF ISAAC TO PROGRESS GENERALLY EWD IN RESPONSE TO
SLIGHTLY GREATER INFLUENCE FROM THE MEAN WESTERLIES ALOFT.
MEANWHILE BY MID-PERIOD THE 06Z AND ESPECIALLY 00Z GFS RUNS MAY
BECOME TOO SLOW AND WRAPPED UP WITH THE SYSTEM EJECTING FROM WRN
CANADA... IN LIGHT OF THE LOW AMPLITUDE NATURE OF THE MEAN FLOW.
ON THE OTHER HAND THE 00Z GEFS MEAN APPEARS TOO FLAT WITH FLOW
DOWNSTREAM FROM THAT EJECTING WRN CANADA SYSTEM EARLY-MID PERIOD.
THE 00Z ECMWF MAY BE A LITTLE SHARP/AMPLIFIED WITH ITS SHRTWV OVER
NEW ENGLAND/CANADIAN MARITIMES EARLY SUN. ALSO THE 00Z ECMWF
BECOMES MORE AMPLIFIED THAN THE GUIDANCE AVERAGE OR CONTINUITY
WITH ITS TROF REACHING WRN CANADA AND THE NRN ROCKIES BY DAY 7 TUE.

OVERALL PREFER A BLEND OF 06Z GFS/00Z ECMWF/00Z ECMWF MEAN SOLNS
FOR DAYS 3-6 FRI-MON TO ACCOUNT FOR SPREAD WITH SYSTEMS AFFECTING
THE NRN CONUS AND SRN CANADA... WITH EACH INDIVIDUAL SOLN WEIGHTED
SUFFICIENTLY LIGHTLY TO DOWNPLAY ANY ISSUES DESCRIBED ABOVE. BY
DAY 7 TUE THE BLEND ADJUSTS TO A 70/30 RATIO OF THE 00Z ECMWF
MEAN/00Z GEFS MEAN AS THERE IS DECENT ENSEMBLE MEAN AGREEMENT IN
THE LARGE SCALE BY THAT TIME BUT THE GEFS MEAN BECOMES A LITTLE
MORE AMPLIFIED THAN OTHER GUIDANCE. THE INITIAL BLEND IS ADJUSTED
OVER THE E-CNTRL CONUS TO REFLECT THE 09Z NHC ADVISORY TRACK FOR
ISAAC.

RAUSCH

Water has already begun to move into backyards along the the Bayou's on the coast of Gulfport. I really don't think some people around here understand storm surge has no relation to only wind and being a Hurricane. Water is 4 feet over the piers at this poing and the height of storm surge is at high tide in the morning and everyone stil have boats on trailors beside their house. Some people are going to be very suprised. The water has completely covered the beaches in some areas already and is lashing the old seawall.
Crow anyone?

LOL
Quoting reedzone:
I have lost all confidence on the NHC... I'm done.


There is no way Isaac travels past 90W. Just no way.
Quoting cheaterwon:


Don't always agree with you hardly ever and your avitar looks like a motorcycle cop (just joking), but you are not a troll you do not say stuff just to inflame people and you contribute greatly to the blog.


Really do appreciate that, thanks.
This storm will be forever known as "Isaac the Choker" never could get it together and was always choking on dry air
Quoting reedzone:
I have lost all confidence on the NHC... I'm done.


Yeah. It has 64kts or greater in both directions on the radar, and a dropsonde with 80mph surface winds, but it is NOT a hurricane, according to NHC...


Maybe it's a dust devil?

A Haboob?

What are they gonna call it next?
New readings from Kermit:

SFMR Peak (10s) Sfc. Wind: 63 knots (~ 72.4 mph)
-------------------

Time: 14:50:00Z
Coordinates: 28.1667N 87.4833W
Acft. Static Air Press: 753.4 mb (~ 22.25 inHg)
Acft. Geopotential Hgt: 2,371 meters (~ 7,779 feet)
Extrap. Sfc. Press: 989.7 mb (~ 29.23 inHg)
D-value: -
Flt. Lvl. Wind (30s): From 164° at 90 knots (From the SSE at ~ 103.5 mph)
Quoting MAweatherboy1:
I would be furious if I was on the plane that got the 81mph winds... You proved beyond any doubt that the system is a hurricane and they totally blow off your reading?


Why your getting paid. Is there a prize for being on the plane that "got the 81mph winds" Maybe this should be like the show "Bachelor Pad" and we kick off planes and their crews when they don't give us Hurricane force winds and have backstabbing and in-fighting. Made for TV!!
It's ssoo tempting to view this as an exact science...and it simply isn't...there's a lot of art to it...tropical meteorology is an attempt to approximate chaos....similar to parenting in that way...
3599. VR46L
Getting very close now ......

3600. ncstorm
Quoting TomballTXPride:
Crow anyone?

LOL


still looking like Ike?
Great work so far is doing the HAARP with Isaac XDD


http://www.tpcg.org/view.php?f=main&p=nws

Flash Flood Watch Issued by NWS New Orleans (Southeastern Louisiana)
Alert:

...FLASH FLOOD WATCH IN EFFECT FROM 7 AM CDT THIS MORNING THROUGH
7 PM CDT WEDNESDAY...

.WIDESPREAD HEAVY RAIN IS EXPECTED TO BEGIN LATER MORNING AND
CONTINUE THROUGH LATE WEDNESDAY AFTERNOON AS SLOW MOVING ISAAC
AFFECTS THE REGION. MANY AREAS ARE LIKELY TO RECEIVE 10 TO 15
INCHES OF RAINFALL OVER A 36 HOUR PERIOD WITH LOCALLY UP TO 20
INCHES POSSIBLE.

...FLASH FLOOD WATCH REMAINS IN EFFECT FROM 7 AM CDT THIS MORNING
THROUGH WEDNESDAY EVENING...

THE FLASH FLOOD WATCH CONTINUES FOR

* PORTIONS OF SOUTHEAST LOUISIANA AND SOUTHERN MISSISSIPPI...
INCLUDING THE FOLLOWING AREAS...IN SOUTHEAST LOUISIANA...

ASCENSION...ASSUMPTION...EAST BATON ROUGE...EAST FELICIANA...
IBERVILLE...LIVINGSTON...LOWER JEFFERSON...LOWER LAFOURCHE...
LOWER PLAQUEMINES...LOWER ST. BERNARD...LOWER TERREBONNE...
NORTHERN TANGIPAHOA...ORLEANS...POINTE COUPEE...SOUTHERN
TANGIPAHOA...ST. CHARLES...ST. HELENA...ST. JAMES...ST. JOHN
THE BAPTIST...ST. TAMMANY...UPPER JEFFERSON...UPPER
LAFOURCHE...UPPER PLAQUEMINES...UPPER ST. BERNARD...UPPER
TERREBONNE...WASHINGTON...WEST BATON ROUGE AND WEST FELICIANA.
IN SOUTHERN MISSISSIPPI...AMITE...HANCOCK... HARRISON...
JACKSON...PEARL RIVER...PIKE...WALTHALL AND WILKINSON.

* FROM 7 AM CDT THIS MORNING THROUGH WEDNESDAY EVENING

* HEAVY RAINFALL IS EXPECTED AS ISAAC MOVES SLOWLY NORTHWESTWARD
TODAY THROUGH WEDNESDAY AFTERNOON. RAINFALL TOTALS ARE EXPECTED
TO RANGE BETWEEN 10 AND 15 INCHES OVER A 36 HOUR PERIOD WITH
LOCALLY UP TO 20 INCHES POSSIBLE.

* RAINFALL RATES MAY OVERWHELM DRAINAGE SYSTEMS AND PUMPS...
RESULTING IN RAPID RUNOFF AND STREET FLOODING. LOW LYING AND
FLOOD PRONE AREAS MAY EXPERIENCE FLASH FLOODING CAPABLE OF
STALLING CARS AND THREATENING HOMES AND BUSINESSES.


Instructions:

A FLASH FLOOD WATCH MEANS THAT CONDITIONS MAY DEVELOP THAT LEAD TO FLASH FLOODING. FLASH FLOODING IS A VERY DANGEROUS SITUATION. YOU SHOULD MONITOR LATER FORECASTS AND BE PREPARED TO TAKE ACTION SHOULD FLASH FLOOD WARNINGS BE ISSUED.



Target Area:




Ascension
Assumption
East Baton Rouge
East Feliciana
Iberville
LAZ069
Livingston
Lower Jefferson
Lower Lafourche
Lower St. Bernard
Lower Terrebonne
Northern Tangipahoa
Orleans
Pointe Coupee
Southern Tangipahoa
St. Charles
St. Helena
St. James
St. John The Baptist
St. Tammany
Upper Jefferson
Upper Lafourche
Upper Plaquemines
Upper St. Bernard
Upper Terrebonne
Washington
West Baton Rouge
West Feliciana

A really high storm surge with this track might push salt water all the way back up to Baton Rouge, or maybe at least half way there, since the river level is only like 4 feet at Baton Rouge last I heard...


Anyway, with this kind of forward speed we are going to see very wide spread 10 inch or greater totals, I think.Morning All...Agree the rain could be problematic but 4ft river level at Baton Rouge.....don't think so....you could walk across the river. You must be talking about depth amount that is needed for fully loaded barge/ship transport.?
Heavy rain 50 mph wind gust!!
Quoting slavicthunder:
I want Al Gore on my television set right now explaining to me why this season's tropical cyclones are all a bunch of wimps. That was An Inconvenient Movie.

From an inconvenient goof.
Quoting TropicalAnalystwx13:
How are they going to ignore their own dropsonde.


Dropsondes give momentary measurements of wind, not sustained wind speed. That 80mph surface measurement could have been a gust - not enough to justify an upgrade if other indications are lower.
Isaac should be upgraded at 2pm or 5pm at the latest. The fact that it wasn't upgraded at 11 am is ridiculous.
TWC hurricane expert said that they did found hurricane winds but it wasn't consistent enough b/c after they found hurricane winds then they found tropical storm winds with the second readings.. So thats they declared a tropical storm still.. I guess that is the excuse that I can find..
Quoting HurricaneDevo:
Live coverage on WDSU in New Orleans. The on-air weatherman just said that rain amounts should not amount to much, and this will be a minimal tropical storm. Not sure where he is getting that information. Gonna be a lot of flooding in New Orleans.



The radar?
Quoting wayfaringstranger:
Isaac is still at TS status based on max sustained winds, which I believe is decieving.

The pressure, storm surge, rain, track, and forward progression once Isaac makes landfall will be comparable to a Cat 1/ 2.

Is there a chance that this hits the mouth of the Miss river?


Darn! I hate that deceptively rigid definition of a hurricane! I suggest we all call the NHC and tell them that we really really really really want them to upgrade this to a hurricane. That ought to help.
there nothing boarded up in down town New Orleans, LA there is going too be a lot of windows blowing out on the higher levels
Quoting Levi32:
They didn't upgrade Isaac. Unbelievable.


Not surprising. Total energy slowly increasing, but it is dispersed over a larger area. Looks like center jogged north and last recon pass missed center to the south.

If it jogs too far north it will never have a chance to develop a good eye and become a hurricane.
I see so many griping about Isaac not being a hurricane. I wonder how many remember Tropical Storm Allison from 2001? She stalled out over Houston, causing massive flooding and several billion dollars in damage. So much so, that Allison is the only tropical storm that I know of to have her name retired. If Isaac stalls out over land in any way, he has the potential to do the same thing. In fact, he's already caused a lot of flooding in Florida. I don't even want to think about potential death toll. There's an old saying, "Hope for the best, but prepare for the worst." IMO, I'm glad that it isn't stronger. For a storm that has already been a nightmare to so many people, it would be a much worse nightmare if it was the Cat 2 or 3 (or higher) some idiots seem to want it to be.
3615. JeffM
Did anyone just see the guy on TWC in NOLA acting like he was having a hard time standing straight up due to the wind while folks were walking by him with zero issues?
Quoting TomballTXPride:
Crow anyone?

LOL


No. I will not take "crow" for stating something that is fact. When the HH have a dropsonde that reports winds at the surface as being 80mph as well as multiple flight level wind speeds of over 100mph, I have to wonder what is going on at the NHC.
Quoting Skyepony:





Thank you!
Quoting TropicalAnalystwx13:
Isaac should be upgraded at 2pm or 5pm at the latest. The fact that it wasn't upgraded at 11 am is ridiculous.

The evidence they had was enough, Isaac should've be upgraded at 11am. Isaac is still a big threat hurricane or not. If Isaac is not a hurricane after 5pm then idk what would happen.
Quoting sonofagunn:


They couldn't find any other instances of winds that fast. One reading could have been a localized gust or waterspout.


Or a Hurricane, but that's neither here-nor-there
Quoting ncstorm:
two blobs on the east coast and tropical storm in the GOM..




The lower East Coast blob is the blob that Isaac cast off over Florida when he split in two, what is the upper blob? Leftover trough? Baby Isaac blob expanding???

I see we are forcasted for more rain in south florida, clouds going from south to north, but who is influencing them? the blobs on the east coast or Isaac in the gulf?
3622. Patrap
Allison..still the Only Tropical Storm to have been Retired.

It dosent have to be a Major for the er, Impact to be deadly. It only has to Linger
Quoting stormchaser19:
Great work so far is doing the HAARP with Isaac XDD


Is there a new facility down there in NOLA?
3624. CJ5
LOL I see a lot of people that needed to be talked away from the ledge. The NHC just got removed from a lot of xmas card lists.

If you were being objective and looking at all of the data you would see that he just has not been able to sustain enough energy to be named a hurricane. He has never been able to close off the eye. He has looks no better than he did 4 days ago. The only change in the past 4 days is a pressure drop. The winds just never caught up and he was never able to spin up tight enough. This is good news to those in his path.
While the rest of the surface specific data did agree with below hurricane status, the dropsonde data the flight level winds pressure made a convincing case.


My guess is that they felt the something was wrong with the dropsonde (perhaps its GPS which is used to get windspeed was malfunctioning).


That plus the deteriorating inner core again = no upgrade
Quoting TropicalAnalystwx13:
Isaac should be upgraded at 2pm or 5pm at the latest. The fact that it wasn't upgraded at 11 am is ridiculous.


HA. They'll come up with some other excuse. Meanwhile, the Louisiana coast will be getting pounded by those hurricane force winds mixing down to the surface from land friction.
I'm not sure if I really get that flight level winds of 100 mph or above aren't translating to at least 74 mph at the surface.
Give the NHC credit for not overhyping the storm. I went through Ike and the barometric pressure was abnormally low for a cat 2 storm. We have a similar situation here. On the other hand both storms have a large wind field which is challenging to deal with.

Let's hope everyone prepared properly. We were without power for 15 days after Ike hit.
3629. SLU
Well the difference between a 70mph TS and a 75mph cat. 1 hurricane is purely immaterial. The damage they will cause is virtually the same. It's all in our minds. Still a mystery why Isaac wasn't upgraded to a hurricane yet though.

MID-LEVEL DRY AIR ENTRAINMENT CONTINUES TO PLAGUE ISAAC. AS SOON AS
THE CYCLONE DEVELOPS INNER-CORE CONVECTION AND THE APPEARANCE OF AN
EYE IN RADAR AND SATELLITE IMAGERY...THE CONVECTION ERODES DUE TO
THE DRY AIR. DESPITE THE FAVORABLE OCEANIC CONDITIONS AND
UPPER-LEVEL OUTFLOW REGIME...ISAAC ONLY HAS ABOUT 12-18 HOURS FOR
FURTHER STRENGTHENING TO OCCUR.
THE OFFICIAL INTENSITY FORECAST IS
SIMILAR TO THE PREVIOUS ADVISORY...WITH ONLY TIMING ADJUSTMENTS
MADE TO THE INTENSITY FORECAST...AND CLOSELY FOLLOWS THE INTENSITY
MODEL CONSENSUS.

Dry air at mid-levels..same story over and over...
Quoting MississippiWx:


No. I will not take "crow" for stating something that is fact. When the HH have a dropsonde that reports winds at the surface as being 80mph as well as multiple flight level wind speeds of over 100mph, I have to wonder what is going on at the NHC.

Experts or bloggers? I go experts. No brainer.

Eat your crow.
Quoting Tazmanian:
there nothing boarded up in down town New Orleans, LA there is going too be a lot of windows blowing out on the higher levels


Not really. Cat1 won't be that bad. Surge is the issue here with Isaac.
3633. CJ5
Quoting MAweatherboy1:
I would be furious if I was on the plane that got the 81mph winds... You proved beyond any doubt that the system is a hurricane and they totally blow off your reading?


That is not how it works.
3634. Gearsts
Quoting stormchaser19:
Great work so far is doing the HAARP with Isaac XDD
lol
One more time

Hurricane Hunters said on the Weather Channel that's the first they've seen those high winds. It will take time for them to work to the surface.

It's ok. They are taking everything seriously. We got the best of the best up there looking. :)
3636. hydrus
Quoting olihomer:


Dropsondes give momentary measurements of wind, not sustained wind speed. That 80mph surface measurement could have been a gust - not enough to justify an upgrade if other indications are lower.


The radar shows a -64kts area about the size of a parish on the NE eye wall, and the SW eye wall is in and out of plus 64kts, again an area about the size of a parish.

It's not an isolated reading, it can't be...
Quoting gulfbreeze:
Heavy rain 50 mph wind gust!!


Might be nice to mention where you are on a map before posting this. Hell for all I know you are living in Egypt and there is a good dust storm going on
3639. ncstorm
for all of those who are redeeming their tickets for the massive crow buffet being offer at WU, please remember to keep your stubs as there will be a giveaway door prize after the big feast..

I redeemed my ticket on sunday..I suggest you all try the boiled crow, it goes down faster..
Quoting Levi32:


It's the extremely favorable upper-level pattern allowing evacuation of air from the storm area. The pressure is therefore falling but the integrated dry air is not allowing a complete eyewall to close off. We've seen plenty of Cat 1 and Cat 2 hurricanes without a closed wall. Only major hurricanes have clear, well-defined eyes as a general rule.


I've seen plenty of TCs at the 970 mb level without a closed eyewall, but they were all in the weakening phase and had one at some point. I can't remember one strengthening to the mid/low 970 mb level without one to get there. I'm not even talking about a cleared or well defined eyewall, just a complete/stable one.
If Isaac has a voice, it would be saying this right now:

"Must... fight... dry... air..... GRRRRRRRRRR... Ok, Time for lunch now." - Isaac

3642. Matt74
What's with the Reed and Cybr teddy bashing? Two good informative bloggers IMO .
Interpretation of dropsonde at NHC






I like my crow with a side of squash....that being said it appears Isaac just ate a huge slug of dry air that is heading for his rickety core....my prediction...55 mph tropical storm by the 5 pm
Isaac is weak sauce :)
What's going on with the storm? I'm on computer at school (at least WU is not banned...)
3647. Patrap
Quoting sunlinepr:


Is there a new facility down there in NOLA?


Well, Henry's Bar on Magazine St. is Open, so that could be a factor.
3648. ncstorm
Quoting AtHomeInTX:
One more time

Hurricane Hunters said on the Weather Channel that's the first they've seen those high winds. It will take time for them to work to the surface.

It's ok. They are taking everything seriously. We got the best of the best up there looking. :)


athome, you sound like you trying to talk people off the ledge..LOL..patience is wearing thin on this blog..
Quoting MississippiWx:


HA. They'll come up with some other excuse. Meanwhile, the Louisiana coast will be getting pounded by those hurricane force winds mixing down to the surface from land friction.


read the discussions and listen to what experts are
saying...for this storm extrapolated data is not
following the normal guidelines...max winds are
not transferring down to the surface...
3650. VR46L
Quoting CJ5:
LOL I see a lot of people that needed to be talked away from the ledge. The NHC just got removed from a lot of xmas card lists.

If you were being objective and looking at all of the data you would see that he just has not been able to sustain enough energy to be named a hurricane. He has never been able to close off the eye. He has looks no better than he did 4 days ago. The only change in the past 4 days is a pressure drop. The winds just never caught up and he was never able to spin up tight enough. This is good news to those in his path.


Thats a realistic post +1,0000,0000



The Gulf in rainbow
3651. Jstn568


With a pressure of 976mb, Isaac should be a weak Category 2 storm. Amazing that it can have such a low pressure and remain just under hurricane status!

Anyone happen to know the lowest pressure recorded for a Tropical Storm?
Quoting wxchaser97:
What happened to the 81mph surface winds from the dropsonde?
REPORTS FROM AIR FORCE AND NOAA HURRICANE HUNTER AIRCRAFT INDICATE
THE CENTRAL PRESSURE HAS DECREASED TO ABOUT 976 MB SINCE THE
PREVIOUS ADVISORY...BUT IT HAS LEVELED OFF OVER THE PAST FEW HOURS.
THE MAXIMUM 850 MB FLIGHT-LEVEL WIND OBSERVED HAS BEEN 89 KT...
WHICH EQUATES TO A SURFACE WIND OF ABOUT 71 KT. HOWEVER...
BIAS-ADJUSTED SFMR SURFACE WINDS HAVE ONLY BEEN AROUND 60-62 KT...
WHICH CORRELATES WELL WITH DROPSONDE BOUNDARY LAYER-DERIVED SURFACE
WINDS. AS SUCH...THE INTENSITY OF ISAAC IS BEING MAINTAINED AT 60
KT...WHICH IS JUST BELOW HURRICANE STATUS.


They are completly wrong, there is not doubt that Isaac is now a Hurricane...
Quoting TomballTXPride:

Experts or bloggers? I go experts. No brainer.

Eat your crow.


Eating crow has to be the most overused/annoying phrase on this blog. And no, I will not. I stick by my statement.
3654. Patrap
Tropical Storm ISAAC Public Advisory

Home Public Adv Fcst Adv Discussion Wind Probs Graphics Archive

US Watch/Warning

000
WTNT34 KNHC 281458
TCPAT4

BULLETIN
TROPICAL STORM ISAAC ADVISORY NUMBER 30
NWS NATIONAL HURRICANE CENTER MIAMI FL AL092012
1000 AM CDT TUE AUG 28 2012

...ISAAC STILL JUST BELOW HURRICANE STRENGTH AS IT CONTINUES
NORTHWESTWARD...


SUMMARY OF 1000 AM CDT...1500 UTC...INFORMATION
-----------------------------------------------
LOCATION...28.1N 88.5W
ABOUT 80 MI...125 KM SSE OF THE MOUTH OF THE MISSISSIPPI RIVER
ABOUT 165 MI...260 KM SE OF NEW ORLEANS LOUISIANA
MAXIMUM SUSTAINED WINDS...70 MPH...110 KM/H
PRESENT MOVEMENT...NW OR 310 DEGREES AT 10 MPH...17 KM/H
MINIMUM CENTRAL PRESSURE...976 MB...28.82 INCHES


WATCHES AND WARNINGS
--------------------
CHANGES WITH THIS ADVISORY...

THE HURRICANE WARNING HAS BEEN REPLACED WITH A TROPICAL STORM
WARNING FROM THE MISSISSIPPI-ALABAMA BORDER EASTWARD TO DESTIN
FLORIDA.

THE TROPICAL STORM WARNING HAS BEEN DISCONTINUED EAST OF DESTIN.

SUMMARY OF WATCHES AND WARNINGS IN EFFECT...

A HURRICANE WARNING IS IN EFFECT FOR...
* EAST OF MORGAN CITY LOUISIANA TO THE MISSISSIPPI-ALABAMA BORDER...
INCLUDING METROPOLITAN NEW ORLEANS...LAKE PONTCHARTRAIN...AND LAKE
MAUREPAS

A HURRICANE WATCH IS IN EFFECT FOR...
* INTRACOASTAL CITY TO MORGAN CITY LOUISIANA

A TROPICAL STORM WARNING IS IN EFFECT FOR...
* THE MISSISSIPPI-ALABAMA BORDER TO DESTIN FLORIDA
* MORGAN CITY TO CAMERON LOUISIANA

A TROPICAL STORM WATCH IS IN EFFECT FOR...
* EAST OF HIGH ISLAND TEXAS TO JUST WEST OF CAMERON LOUISIANA

A HURRICANE WARNING MEANS THAT HURRICANE CONDITIONS ARE EXPECTED
SOMEWHERE WITHIN THE WARNING AREA. PREPARATIONS TO PROTECT LIFE AND
PROPERTY SHOULD BE RUSHED TO COMPLETION.

A HURRICANE WATCH MEANS THAT HURRICANE CONDITIONS ARE POSSIBLE
WITHIN THE WATCH AREA.

A TROPICAL STORM WARNING MEANS THAT TROPICAL STORM CONDITIONS ARE
EXPECTED SOMEWHERE WITHIN THE WARNING AREA.

A TROPICAL STORM WATCH MEANS THAT TROPICAL STORM CONDITIONS ARE
POSSIBLE WITHIN THE WATCH AREA.

FOR STORM INFORMATION SPECIFIC TO YOUR AREA INCLUDING POSSIBLE
INLAND WATCHES AND WARNINGS...PLEASE MONITOR PRODUCTS ISSUED BY
YOUR LOCAL NATIONAL WEATHER SERVICE FORECAST OFFICE.


DISCUSSION AND 48-HOUR OUTLOOK
------------------------------
AT 1000 AM CDT...1500 UTC...THE CENTER OF TROPICAL STORM ISAAC WAS
LOCATED NEAR LATITUDE 28.1 NORTH...LONGITUDE 88.5 WEST. ISAAC IS
MOVING TOWARD THE NORTHWEST NEAR 10 MPH...17 KM/H. A NORTHWESTWARD
MOTION AT A SLIGHTLY SLOWER SPEED IS EXPECTED OVER THE NEXT DAY OR
TWO. ON THE FORECAST TRACK...THE CENTER OF ISAAC SHOULD REACH THE
COASTLINE OF SOUTHEASTERN LOUISIANA AS EARLY AS THIS EVENING.

MAXIMUM SUSTAINED WINDS ARE NEAR 70 MPH...110 KM/H...WITH HIGHER
GUSTS. ISAAC IS EXPECTED TO BECOME A HURRICANE BEFORE MAKING
LANDFALL...AND BEGIN TO SLOWLY WEAKEN AFTER THAT.

TROPICAL STORM FORCE WINDS EXTEND OUTWARD UP TO 185 MILES...295 KM
FROM THE CENTER.

THE LATEST MINIMUM CENTRAL PRESSURE REPORTED BY HURRICANE HUNTER
AIRCRAFT WAS 976 MB...28.82 INCHES.


HAZARDS AFFECTING LAND
----------------------
STORM SURGE...THE COMBINATION OF A STORM SURGE AND THE TIDE WILL
CAUSE NORMALLY DRY AREAS NEAR THE COAST TO BE FLOODED BY RISING
WATERS. THE WATER COULD REACH THE FOLLOWING DEPTHS ABOVE GROUND IF
THE PEAK SURGE OCCURS AT THE TIME OF HIGH TIDE...

* MISSISSIPPI AND SOUTHEASTERN LOUISIANA...6 TO 12 FT
* ALABAMA...4 TO 8 FT
* SOUTH-CENTRAL LOUISIANA...3 TO 6 FT
* FLORIDA PANHANDLE...3 TO 6 FT
* APALACHEE BAY...2 TO 4 FT
* REMAINDER OF FLORIDA WEST COAST...1 TO 3 FT

THE DEEPEST WATER WILL OCCUR ALONG THE IMMEDIATE COAST IN AREAS OF
ONSHORE WINDS. SURGE-RELATED FLOODING DEPENDS ON THE RELATIVE
TIMING OF THE SURGE AND THE TIDAL CYCLE...AND CAN VARY GREATLY OVER
SHORT DISTANCES. FOR INFORMATION SPECIFIC TO YOUR AREA...PLEASE
SEE PRODUCTS ISSUED BY YOUR LOCAL WEATHER SERVICE OFFICE. NEAR THE
COAST...THE SURGE WILL BE ACCOMPANIED BY LARGE AND DANGEROUS WAVES.

WIND...TROPICAL STORM CONDITIONS ARE BEGINNING TO OCCUR NEAR THE
MOUTH OF THE MISSISSIPPI RIVER...AND WILL REACH OTHER PORTIONS OF
THE COASTLINE WITHIN THE TROPICAL STORM AND HURRICANE WARNING AREAS
BY LATE THIS AFTERNOON. HURRICANE CONDITIONS ARE EXPECTED TO REACH
THE COAST BY LATE AFTERNOON.

RAINFALL...ISAAC IS EXPECTED TO PRODUCE TOTAL RAINFALL AMOUNTS OF
7 TO 14 INCHES...WITH POSSIBLE ISOLATED MAXIMUM AMOUNTS OF 20
INCHES...IN SOUTHEASTERN LOUISIANA...SOUTHERN MISSISSIPPI...
SOUTHERN ALABAMA...AND THE EXTREME WESTERN FLORIDA PANHANDLE.
THESE RAINS COULD RESULT IN SIGNIFICANT LOWLAND FLOODING.

TORNADOES...TORNADOES MAY OCCUR ALONG THE NORTHERN GULF COAST TODAY.

SURF...DANGEROUS SURF AND RIP CURRENT CONDITIONS WILL CONTINUE TO
AFFECT THE FLORIDA COASTLINE AND PORTIONS OF THE NORTHERN GULF COAST
FOR THE NEXT DAY OR SO.


NEXT ADVISORY
-------------
NEXT INTERMEDIATE ADVISORY...100 PM CDT.
NEXT COMPLETE ADVISORY...400 PM CDT.

$$
FORECASTER STEWART
All times in GMT. Derived from NHC_ATCF data for TropicalStormIsaac for 28August12pm
27Aug.06am , 24.9n83.7w
27Aug.12pm , 25.8n84.8w , 312.2*NW @ 24.8km/h (15.4mph) 13.4knots , 55knots , 987millibars , TS
27Aug.06pm , 26.1n85.9w , 287.0*WNW@19.2km/h (11.9mph)10.4knots , 60knots , 984millibars , TS
28Aug.12am , 26.7n86.5w , 318.1*NWest @ 14.9km/h (9.3mph) 8.0knots , 60knots , 981millibars , TS
28Aug.06am , 27.4n87.7w , 303.4*WNW @23.7km/h(14.7mph)12.8knots , 60knots , 978millibars , TS
28Aug.12pm , 27.8n88.2w , 312.0*NWest @ 11.1km/h (6.9mph) 6knots ,_, 60knots , 976millibars , TS
2TA5-PortO'Connor :: HUM-Houma :: KAXO-GrandIsle :: 17LA-Venice :: 5LA6-SouthwestPass,MississippiRiver :: EYW-KeyWest

The kinked line is TS.Issac's path on its 6th day as a TropicalStorm
The southeasternmost dot on the longest straight line is TS.Isaac's most recent position

The longest line is a straightline projection through TS.Isaac's 2 most recent positions to its closest approach (within 18miles or 29kilometres) to an inhabited coastline
27Aug.12pm: TS.Isaac had been headed for passage over Venice,Louisiana (middle,17LAblob)
27Aug.6pm: TS.Isaac had been headed for passage over Seadrift(PortO'Connor)Texas (not shown)
28Aug.12am: TS.Isaac had been headed for passage 7.6miles(12.3kilometres)NEast of Venice (top,17LAblob)
28Aug.6am: TS.Isaac was heading for a 9:30pm passage 17.8miles(28.7kilometres)SSWest of Dulac,Louisiana (bottom,nearHUMdumbbell
28Aug.12pm: TS.Isaac was heading for a 29Aug.9:29am passage over GrandIsle,Louisiana in ~[]hours from now (when this was posted) after passing 11.5miles(18.5kilometres)SWest of the E8TankBattery near the SouthwestPass shipping entrance/exit for the MississippiRiver

Copy&paste hum, 29.382n90.714w-29.161n90.868w, kaxo, 5la6-28.894n89.436w, 17la-29.268n89.322w, 17la-29.347n89.263w, 24.627n82.873w, eyw, 23.9n81.5w- 24.0n82.5w- 24.9n83.7w- 25.8n84.8w- 26.1n85.9w, 26.1n85.9w-26.7n86.5w, 26.7n86.5w-27.4n87.7w, 27.4n87.7w-27.8n88.2w, 27.4n87.7w-29.215n90.022w, 5la6-28.825n89.513w into the GreatCircleMapper for a larger map and other information
The previous mapping for comparison
Quoting Tazmanian:
there nothing boarded up in down town New Orleans, LA there is going too be a lot of windows blowing out on the higher levels


Correct me if I'm wrong but building codes in NOLA call for windows that can withstand more than a Cat-1 force winds right?
That's an Eye??


I'm not quite sure why some seem to be upset that Isaac hasn't been officially classified as a hurricane. After all, people living in and around New Orleans aren't going to be able to tell the difference between a 64-knot tropical storm and a 65-knot hurricane; any damage that occurs will occur whether or not Isaac's map symbol is hollow or filled in; the winds will be just as windy and the rains will be every bit as wet whether landfall is made by Tropical Storm Isaac or Hurricane Isaac. And the families of those lost to Isaac on Hispaniola probably don't feel any less sense of heartbreak just because their loved ones were killed by a tropical storm and not a full-fledged hurricane.

It may help to keep this in mind: the hurricane classification is a man-made and arbitrary one; the cyclone spins on and does what it does regardless of what we call it.
Quoting JeffM:
Did anyone just see the guy on TWC in NOLA acting like he was having a hard time standing straight up due to the wind while folks were walking by him with zero issues?


I was just laughing at that. Reminds me of the broadcast from Irene where the kids were goofing around in the background while the guy was trying to show how severe the storm was.
Quoting Tazmanian:
there nothing boarded up in down town New Orleans, LA there is going too be a lot of windows blowing out on the higher levels


Yup, just because the winds haven't gone down to surface level doesn't mean it doesn't get more fun the higher up one goes...
Not only does NHC bust the forecast, now they bust the "now" cast.

Lol.

It was going Big Bend area for center line 36 hours ago, and now it's SW of NOLA.


It's inside my cone from 8 days ago...
Quoting AllStar17:
I'm not sure if I really get that flight level winds of 100 mph or above aren't translating to at least 74 mph at the surface.

I'm trying to think of why they aren't but not much comes to mind. Some people could be in for a surprise with a hurricane coming ashore.

Quoting MississippiWx:


HA. They'll come up with some other excuse. Meanwhile, the Louisiana coast will be getting pounded by those hurricane force winds mixing down to the surface from land friction.

Don't even mention that:) Some people here would get really mad if that happens.
Quoting Felix2007:
Can't they just upgrade it to hurricane just so that people will take it seriously???



My thoughts exactly!
Quoting sunlinepr:
Maybe the Highest winds are 74.99999 mph so it will never achieve hurricane status...

Just, maybe! Maybe!
They are refraining from the upgrade as it will reduce the panic mode by a few percent and that will in turn reduce all the associated problems with the panic mode.
As its going to continue at about the level it is now for another day or so they can always upgrade it later and claim "afterthought" Happened before.
Quoting CJ5:
LOL I see a lot of people that needed to be talked away from the ledge. The NHC just got removed from a lot of xmas card lists.

If you were being objective and looking at all of the data you would see that he just has not been able to sustain enough energy to be named a hurricane. He has never been able to close off the eye. He has looks no better than he did 4 days ago. The only change in the past 4 days is a pressure drop. The winds just never caught up and he was never able to spin up tight enough. This is good news to those in his path.
Yes! And I for one am grateful...
3666. sar2401
Quoting AllStar17:
I'm not sure if I really get that flight level winds of 100 mph or above aren't translating to at least 74 mph at the surface.


Because the flight level winds aren't reaching the surface due to the lack of a closed eye and the ever present dry air. Surface winds are extrapolated after removing contamination for rain also. Isaac may finally become a cat 1 just before landfall or he may remain a strong TS. The difference in actual effects on the ground are trivial. Props to the NHC for reporting the facts based on the science we have available. Given the fact they've been saying a hurricane for the last 5 days, they aren't playing CYA.
Quoting sunlinepr:
That's an Eye??




no, another dry slot.
Quoting reedzone:
You know what Bob, I've had alot of respect for you, watched your videos and you have the nerve to make that statement.. Your not a MET, your a bully.. I did NOTHING to you and start bullying me on here. That's not professorial sir.


Says the guy with the "won't pass 85W" Isaac prediction and "1400 mile wide 5-day cones" last year.

I think the intensity forecast hurt the track forecast, because a stronger storm would have turned north by now.

Just my opinion.
Quoting Patrap:


Well, Henry's Bar on Magazine St. is Open, so that could be a factor.


Ahh, I knew those antennas in Bourbon Street were strange....
Quoting SFLWeatherman:
Wellington on 8/28/12


What a flood and it extends to at least FT. Pierce.
3671. Patrap
Quoting kidd5433:


Correct me if I'm wrong but building codes in NOLA call for windows that can withstand more than a Cat-1 force winds right?



not sure dont live in NOLA so i would not no that ask pat
3673. mbar62
Quoting prweatherwatcher:


They are completly wrong, there is not doubt that Isaac is now a Hurricane...


It's not a hurricane and is deteriorating on satellite. I seriously doubt it will achieve hurricane strength before landfall due primarily to dry air entrainment. We should all be rather happy about that.
Has the Army Corps closed the big structure gates they built to stop storm surge? It would be cool to see those in action!
Quoting sunlinepr:
That's an Eye??




Hard to tell anymore could be some more dry air but it sure looks like one to me
Product: Air Force Vortex Message (URNT12 KNHC)
Transmitted: 28th day of the month at 15:09Z
Aircraft: Air Force Aircraft (Last 3 digits of the tail number are 306)
Storm Number & Year: 09L in 2012
Storm Name: Isaac (flight in the North Atlantic basin)
Mission Number: 31
Observation Number: 12
A. Time of Center Fix: 28th day of the month at 14:26:40Z
B. Center Fix Coordinates: 27°59'N 88°35'W (27.9833N 88.5833W)
B. Center Fix Location: 164 miles (264 km) to the SSE (147°) from New Orleans, LA, USA.
C. Minimum Height at Standard Level: 1,217m (3,993ft) at 850mb
D. Estimated (by SFMR or visually) Maximum Surface Wind: 53kts (~ 61.0mph)
E. Location of the Estimated Maximum Surface Wind: 38 nautical miles (44 statute miles) to the S (188°) of center fix
F. Maximum Flight Level Wind Inbound: From 283° at 61kts (From the WNW at ~ 70.2mph)
G. Location of Maximum Flight Level Wind Inbound: 42 nautical miles (48 statute miles) to the S (187°) of center fix
H. Minimum Sea Level Pressure: 976mb (28.82 inHg) - Extrapolated
I. Maximum Flight Level Temp & Pressure Altitude Outside Eye: 19°C (66°F) at a pressure alt. of 1,525m (5,003ft)
J. Maximum Flight Level Temp & Pressure Altitude Inside Eye: 20°C (68°F) at a pressure alt. of 1,524m (5,000ft)
K. Dewpoint Temp (collected at same location as temp inside eye): 20°C (68°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, Radar, Wind, Pressure and Temperature
N. Fix Level: 850mb
O. Navigation Fix Accuracy: 0.02 nautical miles
O. Meteorological Accuracy: 1 nautical mile
Remarks Section:
Maximum Flight Level Wind: 89kts (~ 102.4mph) in the northeast quadrant at 13:17:00Z
Sea Level Pressure Extrapolation From: 850mb
Quoting Bluestorm5:
What's going on with the storm? I'm on computer at school (at least WU is not banned...)

Hey Blue, HH found 100mph flight level winds, 81mph surface winds from the dropsonde, and 976-975mb pressure. My school doesn't ban WU as well.
I have to leave Houston tomorrow morning to be in Jacksonville Florida by 7am for a State Farm assignment. Do you all think I-10 will be okay to travel tomorrow? I didn't think about driving through the storm before excepting the assignment.
Quoting ncstorm:


athome, you sound like you trying to talk people off the ledge..LOL..patience is wearing thin on this blog..


Yeah, I've had to be talked off that ledge a time or two myself. lol. I find sleep helps tremendously with patience.
3680. jpsb
Quoting sunlinepr:



Look at the huge expanding band of dry air to his north. I wonder where that is coming from? Must be sinking air from high in the atmosphere, bad news for Issac, good news for the gulf coast.
Quoting Matt74:
What's with the Reed and Cybr teddy bashing? Two good informative bloggers IMO .


No one is bashing anyone, but to come on here and down-trod others as not being "mets" while missing the forecast repeatedly aka..won't get past 85W.., or having a 1400-mide wide cone at 5-days is noteworthy.

And then to insult the NHC for not hyping a 70 mph storm is the icing on the cake.
Product: NOAA Vortex Message (URNT12 KWBC)
Transmitted: 28th day of the month at 15:08Z
Aircraft: Lockheed WP-3D Orion (Reg. Num. N42RF)
Storm Number & Year: 09L in 2012
Storm Name: Isaac (flight in the North Atlantic basin)
Mission Number: 30
Observation Number: 34
A. Time of Center Fix: 28th day of the month at 14:35:33Z
B. Center Fix Coordinates: 27°59'N 88°33'W (27.9833N 88.55W)
B. Center Fix Location: 165 miles (266 km) between the SE and SSE (146°) from New Orleans, LA, USA.
C. Minimum Height at Standard Level (Undecoded): NA NA
D. Estimated (by SFMR or visually) Maximum Surface Wind: 60kts (~ 69.0mph)
E. Location of the Estimated Maximum Surface Wind: 13 nautical miles (15 statute miles) to the WSW (254°) of center fix
F. Maximum Flight Level Wind Inbound: From 312° at 59kts (From the NW at ~ 67.9mph)
G. Location of Maximum Flight Level Wind Inbound: 54 nautical miles (62 statute miles) to the SW (233°) of center fix
H. Minimum Sea Level Pressure: 980mb (28.94 inHg) - Extrapolated
I. Maximum Flight Level Temp & Pressure Altitude Outside Eye: 14°C (57°F) at a pressure alt. of 2,446m (8,025ft)
J. Maximum Flight Level Temp & Pressure Altitude Inside Eye: 19°C (66°F) at a pressure alt. of 2,437m (7,995ft)
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: Poorly Defined
M. Eye Shape: Not Available
N. Fix Determined By: Penetration, Radar, Wind, Pressure and Temperature
N. Fix Level: Other - Not surface, 1500ft, 925mb (if vortex is newer than about mid 90's; see note for more), 850mb, 700mb, 500mb, 400mb, 300mb or 200mb
Remarks Section:
MAX OUTBOUND FL WIND AND MAX FL WIND 90 KT E QUAD 14:50:00Z
SEC MAX FL WIND 68 KT BRNG:43 deg RNG:96 nm
SLP EXTRAP FROM 8k ft
Quoting nrtiwlnvragn:
Interpretation of dropsonde at NHC








This is good info, so thanks. I knew that they would like to see the average over the boundary layer, but if you do that this is still a HU.

Slight kink, but a much higher wind speed bulge just above.


For those interested:

See below, select 12:25UTC reading at the top

Dropsonde Report
Quoting MississippiWx:


Eating crow has to be the most overused/annoying phrase on this blog. And no, I will not. I stick by my statement.


A close second is "NHC will make it a Hurricane in their 10AM update"
Quoting Patrap:


Thats the eye well kindof
Quoting wxchaser97:

Hey Blue, HH found 100mph flight level winds, 81mph surface winds from the dropsonde, and 976-975mb pressure. My school doesn't ban WU as well.
How the heck that's not a hurricane yet? Ugh... hopefully my school ends sooner, but that's two hours away.
The weeping and wailing and blaming the NHC this morning is hilarious. Reminds me of that time in kindergarten where one kid spilled his chocolate milk on another kid's blankie...

Quoting CJ5:
LOL I see a lot of people that needed to be talked away from the ledge. The NHC just got removed from a lot of xmas card lists.

If you were being objective and looking at all of the data you would see that he just has not been able to sustain enough energy to be named a hurricane. He has never been able to close off the eye. He has looks no better than he did 4 days ago. The only change in the past 4 days is a pressure drop. The winds just never caught up and he was never able to spin up tight enough. This is good news to those in his path.
3688. Patrap
For the record..

Storms don't have Ear's nor wi-fi last we looked.

Impact counts, not any, er,..."Phrasing".



ISAAC RainbowTop Loop


3689. ncstorm
Quoting AtHomeInTX:


Yeah, I've had to be talked off that ledge a time or two myself. lol. I find sleep helps tremendously with patience.


LOL..this season in tropical forecasting has debunked a lot of experts..its a tough job for them and they can have it
lots.of.surfers.in.el.salvador..best.time.of.the.yr
Quoting Neapolitan:
I'm not quite sure why some seem to be upset that Isaac hasn't been officially classified as a hurricane. After all, people living in and around New Orleans aren't going to be able to tell the difference between a 64-knot tropical storm and a 65-knot hurricane; any damage that occurs will occur whether or not Isaac's map symbol is hollow or filled in; the winds will be just as windy and the rains will be every bit as wet whether landfall is made by Tropical Storm Isaac or Hurricane Isaac. And the families of those lost to Isaac on Hispaniola probably don't feel any less sense of heartbreak just because their loved ones were killed by a tropical storm and not a full-fledged hurricane.

It may help to keep this in mind: the hurricane classification is a man-made and arbitrary one; the cyclone spins on and does what it does regardless of what we call it.


I agree, but I think it might matter for insurance reason? Maybe? Not sure but I can see that being the case with the way insurance companies love to dodge actually paying out for things.
Quoting MississippiWx:


HA. They'll come up with some other excuse. Meanwhile, the Louisiana coast will be getting pounded by those hurricane force winds mixing down to the surface from land friction.


The forecast is still a hurricane at landfall and west of NOLA. That is what we are prepared for.
Quoting Patrap:


Well, Henry's Bar on Magazine St. is Open, so that could be a factor.


Wonder if soul food cafe is open off magazine...

man i love that place!
Quoting Matt74:
What's with the Reed and Cybr teddy bashing? Two good informative bloggers IMO .


Haters going to Hate....some were after Taz last night..

I guess their "Ignore" doesn't work or they just are trying to pad their comments....I love the newbie that registered Aug 19th and already has nearly 500 comments. Must be trying for a prize...
3695. sar2401
Quoting Terradad:



My thoughts exactly!


No. They upgrade based on measurable data. They don't do it so people will take it seriously. Do you think anyone who knows Isaac is at 70 mph and not taking it seriously will suddenly start to prepare 12 hours before landfall if it was 75 mph? All the watches and warnings have been up for days. Those who paid attention are in good shape. For the others, well, you can't cure stupid, even if was a cat 5.
3696. WxLogic
I see NHC kept it at 70MPH. Based on the discussion dry air still at it.

Like I mentioned before... it might try again to regenerate a well defined eye, but I do believe it will be the last attempt.
3697. Patrap
Quoting cheaterwon:
I have to leave Houston tomorrow morning to be in Jacksonville Florida by 7am for a State Farm assignment. Do you all think I-10 will be okay to travel tomorrow? I didn't think about driving through the storm before excepting the assignment.


I-12 is a much better Route as its N of Lake P.

Quoting Bluestorm5:
How the heck that's not a hurricane yet? Ugh... hopefully my school ends sooner, but that's two hours away.

Exactly, later today then it should be a hurricane. Still going to have the same impacts from Isaac.
Quoting Neapolitan:
I'm not quite sure why some seem to be upset that Isaac hasn't been officially classified as a hurricane. After all, people living in and around New Orleans aren't going to be able to tell the difference between a 64-knot tropical storm and a 65-knot hurricane; any damage that occurs will occur whether or not Isaac's map symbol is hollow or filled in; the winds will be just as windy and the rains will be every bit as wet whether landfall is made by Tropical Storm Isaac or Hurricane Isaac. And the families of those lost to Isaac on Hispaniola probably don't feel any less sense of heartbreak just because their loved ones were killed by a tropical storm and not a full-fledged hurricane.

It may help to keep this in mind: the hurricane classification is a man-made and arbitrary one; the cyclone spins on and does what it does regardless of what we call it.


I think you're about to set the blog record for most (+) with this comment.

Your Stephanie Abrams comment yesterday was right-on as well.
To all of you advocating objectivity, rationality and sensibility:

Isn't it a little early for y'all to be drinking so heavily?!
Quoting jpsb:

Look at the huge expanding band of dry air to his north. I wonder where that is coming from? Must be sinking air from high in the atmosphere, bad news for Issac, good news for the gulf coast.


Considering the bad situation for NOrleans, feel good to see that we don't have a Katrina or one of the Cat3 or more posted here two nights ago... by comparing models....
Quoting Patrap:
Allison..still the Only Tropical Storm to have been Retired.

It dosent have to be a Major for the er, Impact to be deadly. It only has to Linger


Yup. I found out the hard way. Come back to GLP so we can make fun of you.
Water vapor images from GEOS-14 shows that dry air began disrupting the core again around 10:30am est, giving the NHS good reason not to upgrade to a hurricane.

LINK

However the storm's northward jog has caused a large increase in wind speed the buoy on the southern tip of the mississippi delta:

LINK

Chance of precipitation is 80% now in WPB!!! :/ no
Quoting cheaterwon:
I have to leave Houston tomorrow morning to be in Jacksonville Florida by 7am for a State Farm assignment. Do you all think I-10 will be okay to travel tomorrow? I didn't think about driving through the storm before excepting the assignment.

This might help you make a decision. http://www.hpc.ncep.noaa.gov/tropical/qpf/Isaac_ra infall.gif
Quoting sunlinepr:
That's an Eye??




Maybe a Belly-button
3707. Patrap
New Orleans
NEXRAD Radar

Storm Relative Mean Radial Velocity 0.5° Elevation
Range 124 NMI

JeffMasters has created a new entry.
Massive shield of 65kts or greater winds in both directions, according to radar, is at the mouth of the river and closing distance.
Quoting Neapolitan:
I'm not quite sure why some seem to be upset that Isaac hasn't been officially classified as a hurricane. After all, people living in and around New Orleans aren't going to be able to tell the difference between a 64-knot tropical storm and a 65-knot hurricane; any damage that occurs will occur whether or not Isaac's map symbol is hollow or filled in; the winds will be just as windy and the rains will be every bit as wet whether landfall is made by Tropical Storm Isaac or Hurricane Isaac. And the families of those lost to Isaac on Hispaniola probably don't feel any less sense of heartbreak just because their loved ones were killed by a tropical storm and not a full-fledged hurricane.

It may help to keep this in mind: the hurricane classification is a man-made and arbitrary one; the cyclone spins on and does what it does regardless of what we call it.

Dude. Two days in a row with profound statements. Do you have another one lined up for later today, or are you saving it for tomorrow?
Quoting SherwoodSpirit:


I was just laughing at that. Reminds me of the broadcast from Irene where the kids were goofing around in the background while the guy was trying to show how severe the storm was.

lol...
I remember when Andrew was making landfall here in LA...reporter was standing outside of a popular restaurant and noted how the palm trees were extremely bent over from the winds... they were planted in the ground that way and formed an "x". I don't think he lasted long at the station.
Quoting prweatherwatcher:


They are completly wrong, there is not doubt that Isaac is now a Hurricane...

And, from which university did you receive your degree in meteorlogy? They will be proud to know that you are the only person to call Isaac a hurricane, with every single Ph.D., meteorologist, climatologist, and hurricane hunter staff member with actual data calling it, still, a tropical storm.

Quoting kidd5433:


A close second is "NHC will make it a Hurricane in their 10AM update"
eating crow does need replacement. how about "once again showing my want of intellect ".
Quoting biff4ugo:
Has the Army Corps closed the big structure gates they built to stop storm surge? It would be cool to see those in action!
about 30 minutes ago....
Quoting Patrap:


I-12 is a much better Route as its N of Lake P.

Stay well north or leave now
Here comes the dry air injection to stumble Isaac's ambitions again. Check the WV loop. If this stays a TS and never makes Cat1, it is a huge win for anyone making non-flood related insurance claims from this storm. In that case, the special hurricane deductible doesn't apply.
Not a hurricane? I don't like it, but the NHC does know better than I do.
Quoting seer2012:
What a flood and it extends to at least FT. Pierce.


Thankfully most of the flooding in Ft Pierce seems to have subsided. Rains stopped last night around 6pm or so and we even have sunny skies right now. Not sure if anything else is on it way though.
Quoting osuwxguynew:


This is good info, so thanks. I knew that they would like to see the average over the boundary layer, but if you do that this is still a HU.

Slight kink, but a much higher wind speed bulge just above.


For those interested:

See below, select 12:25UTC reading at the top

Dropsonde Report


It is close and in my opinion they could have gone either way, why Stewart chose conservative, don't know. I would have gone HU.
Quoting NoloContendere:
The weeping and wailing and blaming the NHC this morning is hilarious. Reminds me of that time in kindergarten where one kid spilled his chocolate milk on another kid's blankie...



Not so funny -- just sad. To think that there are many, many lurkers out there reading this nonsense.

The difference that even 10 miles per hours is going to make is nothing -- the slow movement and the length of time that the winds and rain will be around is what will cause the trouble.

If you get a thunderstorm that has one big wind gust, that's the end of your damage right? What if that same wind gust happens 30 times in the next 4 hours -- what will that do the sign or the tree or the carport?

This is what they are talking about as to the effects.
3722. divdog
Quoting leftlink:
Water vapor images from GEOS-14 shows that dry air began disrupting the core again around 10:30am est, giving the NHS good reason not to upgrade to a hurricane.

LINK

However the storm's northward jog has caused a large increase in wind speed the buoy on the southern tip of the mississippi delta:

LINK

Where can I find any support for north jog
3723. sar2401
Quoting Agathorn:


I agree, but I think it might matter for insurance reason? Maybe? Not sure but I can see that being the case with the way insurance companies love to dodge actually paying out for things.


The NHC is not in the business of enhancing insurance coverage, if that's even a factor. They report the facts that science gives them. That's their only concern. Since they have had a blown intensity forecast for the last five days, I think it's amazing that some NHC suit isn't insisting that the forecasters finally make it a hurricane.
3724. CJ5
Quoting sunlinepr:
That's an Eye??




No it is not
Quoting presslord:
To all of you advocating objectivity, rationality and sensibility:

Isn't it a little early for y'all to be drinking so heavily?!


Cheers! gulp gulp....
NOLA Quarter Cam....

Link
3727. CJ5
Quoting presslord:
To all of you advocating objectivity, rationality and sensibility:

Isn't it a little early for y'all to be drinking so heavily?!


There is a hurricane..err tropical storm in the area, it is never to early to drink!
Quoting Neapolitan:
I'm not quite sure why some seem to be upset that Isaac hasn't been officially classified as a hurricane. After all, people living in and around New Orleans aren't going to be able to tell the difference between a 64-knot tropical storm and a 65-knot hurricane; any damage that occurs will occur whether or not Isaac's map symbol is hollow or filled in; the winds will be just as windy and the rains will be every bit as wet whether landfall is made by Tropical Storm Isaac or Hurricane Isaac. And the families of those lost to Isaac on Hispaniola probably don't feel any less sense of heartbreak just because their loved ones were killed by a tropical storm and not a full-fledged hurricane.

It may help to keep this in mind: the hurricane classification is a man-made and arbitrary one; the cyclone spins on and does what it does regardless of what we call it.


Those who question the NHC and complain about upgrades are just inexperienced and probably young and immature young adults or teenagers.
Among Isaac's other issues, I wondering what the effect will be over the next 24 hours of his lack of connection to any source of deep moisture from the Caribbean. How can Isaac fight off the dry air if his circulation is cut off from the Caribbean ?
Mississippi River Cam

Link
3731. zawxdsk
Quoting Neapolitan:
I'm not quite sure why some seem to be upset that Isaac hasn't been officially classified as a hurricane. After all, people living in and around New Orleans aren't going to be able to tell the difference between a 64-knot tropical storm and a 65-knot hurricane; any damage that occurs will occur whether or not Isaac's map symbol is hollow or filled in; the winds will be just as windy and the rains will be every bit as wet whether landfall is made by Tropical Storm Isaac or Hurricane Isaac. And the families of those lost to Isaac on Hispaniola probably don't feel any less sense of heartbreak just because their loved ones were killed by a tropical storm and not a full-fledged hurricane.

It may help to keep this in mind: the hurricane classification is a man-made and arbitrary one; the cyclone spins on and does what it does regardless of what we call it.


I +1'd your comment, but I would like to make a counterpoint. A hurricane is a human-made storm distinction, like you said, but there is a psychological effect. As much as the storm is being hyped right now by TWC, there will still be enough people who do not take a 'Tropical Storm' seriously because its not a hurricane. In S LA, plenty of folks won't leave until it because a storm of a given magnitude because they say that they say that they know what that category of storm is capable of. A tropical storm just won't cut it - even if you were to tell them that this is the strongest tropical storm ever.

I would say (and I think the blog would probably agree) that Isaac has the potential impact of more like a low end Hurricane destruction with the expected rainfall and storm surge. If it take calling it a hurricane to get people a little more on edge about leaving, then call it a hurricane. Calling it a 'Tropical Storm' is arbitrary, too, especially with the dropsonde information and also a couple of the offshore buoys http://w1.weather.gov/data/obhistory/KVOA.html supporting the case for hurricane.

Its easy for a layman to call a Tropical Storm just another tropical storm - and Isaac versus 2011's Don is not a fair comparison.
Quoting zoomiami:


Not so funny -- just sad. To think that there are many, many lurkers out there reading this nonsense.

The difference that even 10 miles per hours is going to make is nothing -- the slow movement and the length of time that the winds and rain will be around is what will cause the trouble.

If you get a thunderstorm that has one big wind gust, that's the end of your damage right? What if that same wind gust happens 30 times in the next 4 hours -- what will that do the sign or the tree or the carport?

This is what they are talking about as to the effects.


I agree, somewhat. But, for a storm that will linger for 12 hours, with repeated gusts, 10 fewer miles per hour of wind will make a huge difference. I would rather 10 miles per hour slower wind speed, all day.
With only some quick observation my thoughts haven't changed too much from last evening. Isaac will continue to strengthen gradually (no more opps for RI) as coastal waters will be less warm that the areas Isaac has just traversed.

Sat presentation is better, looks like a duck, walks like duck, quacks like a duck, well...it's probably a duck! That's the way it needs to be treated. Isaac may sneak up on folks, 80 mph winds with higher gusts is no walk in the park. Winds will likely landfall stronger as Isaac's LLC earnestly tries to spin up the broader circulation at the mid-levels which is still slightly asymmetrical. Isaac is wobbler in stature, not truly a standing-up vertical storm which also means, I think, that he'll never really mature.

Still ingesting dry air, still trying to wall-up a solid inner core. Obviously, the ingestion of dry air has not weakened him as he has tried to intensify, so I suspect it will be a weakening deterrent any further towards landfall. It probably does mean that he want increase intensity too terribly much either. We may reach 90-type range of winds at landfall, but that'd be about tops I think.

Track. The general rule of thumb here has been weaker means west, but Isaac has continued to climb gradually on a nwest motion. I suspect that will continue and he'll move further east from my original thoughts of landfall at Mud Lake. 1012mb pressures have relaxed west and nwest of the sytem, still tight up against the storm on the right side. So, I suspect the slowed (mentioned that last night too) 10 mph nwest movement will continue. He will also slow fwd speed further to almost a stall nearing landfall. That relaxed weakness is starting to show him an escape route, but it won't be quick at all. I'm thinking the current motion, some gradual strengthening will set him on a course over Grand Isle, the eastern side of NOLA, and almost stalling as it tries to turn due north/poleward.

That's enough for now, fingers tired, out of breath! ;) And, I'm sure everyone would appreciate a shorter statement - well, here it is:

Isaac is a VERY serious storm still. It's lack of further classification has likely generated considerable apathy. Mistake. There will be very long periods of hurricane force winds on land. He will not be a "passing-thru" system. There will be lots of rain and flooding. And, there will be above estimated surge, imo, as well. BE DILIGENT, don't let your guard down; otherwise, Isaac will be a killer!
3734. Jstn568
Link

Awesome wind map for the U.S.!
Mississippi River is finally rising:



What side of the flood gates are they measuring the height on? There might be a plan to let salt water in to put pressure on both sides of the flood walls so the y perform better, if I am reading this correctly.
You would rather have a fast moving Cat 1-2 than a slow high-grade TS lingering over you for 24 hours.....We can only hope now for minimal loss of life and that first responders are ready to go in to assist victims from the flooding over the next several days.
3737. Dsntslp
Quoting Agathorn:


I agree, but I think it might matter for insurance reason? Maybe? Not sure but I can see that being the case with the way insurance companies love to dodge actually paying out for things.
Doesn't it make a difference in people being able to qualify for FEMA help/funds after the storm passes? Or, am I mistaken...?
Quoting Agathorn:


Thankfully most of the flooding in Ft Pierce seems to have subsided. Rains stopped last night around 6pm or so and we even have sunny skies right now. Not sure if anything else is on it way though.
Saint Lucie West at Publix is still a mess. Avoid it if you can.
Dry air still drying up feeder bands...won't get near the rain they are talking about...but, i think with those pressures and wave heights, a CAT 2 storm surge will be the worst part of it, especially the angle that it will be hitting Louisiana
Water rising in Mobile Bay. Just came from the causeway and went through a decent squall. It good now, but I'm betting the causeway will be closed by this afternoon.
Quoting WxNerdVA:
Not a hurricane? I don't like it, but the NHC does know better than I do.

It's a hurricane watch at landfall
Here is the latest water vapor image, just 20 minutes ago. The little blob on the left is rapidly expanding, so dry air will be pushed out soon.

Quoting leftlink:

Here is the latest water vapor image, just 20 minutes ago. The little blob on the left is rapidly expanding, so dry air will be pushed out soon.



Same image, 4 minutes go. Note the difference.

That dry air was really a blessing.

Not only has it kept Isaac from becoming a hurricane, it dried out his N/NE quadrants so his rain field on the north has been limited to this point.

However, with Isaac's organization improving, that moisture is being pulled around where it will likely extend to the AL/FL border.
3744. keisa90
Think we have a hurricane:

Flt. Lvl. Wind (30s):From 183° at 91 knots (From the S at ~ 104.6 mph)
Air Temp:18.0°C* (~ 64.4°F*)
Dew Pt: 18.0°C* (~ 64.4°F*)
Peak (10s) Flt. Lvl. Wind:93 knots (~ 106.9 mph)
SFMR Peak (10s) Sfc. Wind:66 knots (~ 75.9 mph)
Quoting reedzone:


Me a troll?? Say that to the bloggers who enjoy my posts on here.. I have some haters but really a troll?? That's low man... I have a right to make predictions and maybe you haven't read my post one night saying I was WRONG in Isaac not busting the mid level ridge. I was WRONG in Isaac going up the East Coast. I was WRONG WRONG WRONG.. ok?
ok, we're used to it. It's not the getting forecasts wrong part that bothers me/us. It's the thinking that you know more than the Dr. or the NHC.
3746. keisa90
Another Ob:


Peak (10s) Flt. Lvl. Wind:94 knots (~ 108.1 mph)
SFMR Peak (10s) Sfc. Wind:66 knots (~ 75.9 mph)
Quoting leftlink:
Water vapor images from GEOS-14 shows that dry air began disrupting the core again around 10:30am est, giving the NHS good reason not to upgrade to a hurricane.

LINK

However the storm's northward jog has caused a large increase in wind speed the buoy on the southern tip of the mississippi delta:

LINK



Actually BURL1 has been in the high 40 kts with gusts to around 55 kts all morning. KVOA to the NE of the COC 60 kts gusting 66.
3748. syn627
Quoting JasonRE: Well I guess this storm isn't as serious as I've been reading about. Our company in Lafayette has us open tomorrow for business. Am I losing my mind? I've been tracking this thing since it began and now I'm going to have to sit through this at work? It sure as hell doesn't seem to bother the owner enough.%uFFFD
Quoting CybrTeddy:

Your workplace will *probably* be cancelled tomorrow AM, they usually make that decision come early once they really know where it is going as Isaac will be approaching landfall. I doubt they're going to make you drive to work in TS force winds. My transmitter in my car blew out during TS Debby at that was only in 40mph sustained.
They may change their mind as the day wears on (hopefully). I'm in Lafayette as well and had 2 separate Dr. appts scheduled tomorrow ... both just called within the past 30 minutes to let me know they were cancelled.

It's getting rather breezy here already (feels good) and surprisingly enough we've already had a hibiscus tree in a large, heavy pot blow over and that was in a small, fenced-in backyard.

I didn't anticipate the wind being too terribly gusty here since the current projected path is northeast of us so I hadn't planned to relocate potted plants, outdoor decorations, lawn furniture, etc. but after that big pot blew over ... I changed my mind.
Quoting leftlink:
Water vapor images from GEOS-14 shows that dry air began disrupting the core again around 10:30am est, giving the NHS good reason not to upgrade to a hurricane.

LINK

However the storm's northward jog has caused a large increase in wind speed the buoy on the southern tip of the mississippi delta:

LINK



Nothward jog? at this point a jog can make a huge difference when it come to landfall. You think it will hit where the NHC says it will?
People:

Ohh it's just a Tropical Storm with 70 mph winds, lets go to the beach to see the waves and feel the wind !!!

then

Ohh it's a Hurricane with 75 mph, lets go home to be safe !!!

3752. syn627
Quoting Jstn568:
Link

Awesome wind map for the U.S.!
It is awesome, thanks for the link.
I don't particularly care whether they official call this a hurricane or not. Nor do I expect this insignificant distinction to alter people's behavior or their impression about the experts who hyped this storm. Ultimately, the truth that cannot be deflected is this:

The people who ignored the hysterical warnings were CORRECT.

And this, in my opinion, is a problem.


Starting to get purty windy here n sprinklin rain