Isaac is strengthening

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

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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

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What's all that scurrying about noise coming from the dirrection of Panama City, FL?
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Quoting ncstorm:
Were the waters in the GOM the same temp when Debby went through??..its not about temps in the GOM that intensify a storm..there are many other variables that come into play


Amen. And so far the major impediment has been
the internal structure of the storm itself....
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For Now, I'm still going with the west side of the cone until about 0600 Sunday morning.




I'll say IMO most likely U.S. landfall is near Mobile Bay, at least for now.


The fact the Euro initially turned harder N than the storm is actually going, yet still hit that area, is a good reason to think the left side of the 3 to 5 day range should be considered most.
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Quoting yonzabam:


Very mountainous. Isaac will be a raggedy boy when he exits back over water.
RIP Issac
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Quoting cgthms:
XTRAP is not a model . It just shows the direction the storm is moving at that given moment.


*Facepalm*
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Quoting BahaHurican:
Dunno bout the mass deaths in Cuba. They have, generallly speaking, had a better record of storm vigilance, and attention to timely evacuation. Haiti has the bigger problem.
Whoops, why did I said both countries? I meant Haiti with the mass deaths. There will be flooding in both countries though...
Member Since: August 1, 2011 Posts: 23 Comments: 7507
Quoting ncstorm:
Were the waters in the GOM the same temp when Debby went through??..its not about temps in the GOM that intensify a storm..there are many other variables that come into play


Give that man a Gold Star!!!!! If Gulf water temp were the only issue, there would be a major hurricane sitting in the Gulf constantly from May to September...
Member Since: August 13, 2007 Posts: 0 Comments: 10458
XTRAP is not a model . It just shows the direction the storm is moving at that given moment.
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Quoting ncstorm:
Were the waters in the GOM the same temp when Debby went through??..its not about temps in the GOM that intensify a storm..there are many other variables that come into play

Isaac will have the ventilation Ernesto did before landfall with an upper level low backing southwest.
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Quoting weatherguy03:
Levi and I were talking about this on FB last night on the strange direct track NW through the Eastern GOM and why there wasnt more of a bend off to the North and NE later in the track. Well you can see the first run 12Z models starting to show that bend. Makes more sense to me.



Based on my observations and thoughts I would be inclined to start the bending around the Tampa area and gradually bend N/NNE/NE from there on.
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Quoting oracle28:


I see the XTRP update has not changed its forecast.

Once this thing clears Cuba, the XTRP will start to become the model of choice.

You're being sarcastic, right?
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Quoting opal92nwf:
When was the last time someone saw a hurricane landfall in North Korea?
Nobody, since K-J-I-L became dicatator Over 9000 years ago!
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Quoting FOREX:


Anyone familiar with the topography of the part of Cuba Isaac will spin over? Will it run into the highest peaks or go West of them???


Very mountainous. Isaac will be a raggedy boy when he exits back over water.
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Quoting HurricaneDean07:

I believe the NHC needs to be upping the Intensity when Isaac gets through with the Islands... QUICKLY.
The Gulf Coast could easily get cuaght off-guard with the NHC forecasting a Category 1, and yet Isaac could go through RI in the Eastern Gulf and become a Category 3.


Yes but he hasn't exactly matched the intensity forecasts yet. And that is hardest to predict. I'm sure they are taking this seriously and are a lot more concerned with the forecast than anyone. Give it time. They're the best at what they do.
Member Since: August 24, 2010 Posts: 0 Comments: 459
Member Since: August 6, 2011 Posts: 4 Comments: 33491
144. FOREX
Quoting HurricaneDean07:

I believe the NHC needs to be upping the Intensity when Isaac gets through with the Islands... QUICKLY.
The Gulf Coast could easily get cuaght off-guard with the NHC forecasting a Category 1, and yet Isaac could go through RI in the Eastern Gulf and become a Category 3.


I agree. Atleast have a CAT2 at landfall people might take it seriously. A CAT1 and all it does is tell people not to worry about it.
Member Since: August 17, 2011 Posts: 0 Comments: 846
Were the waters in the GOM the same temp when Debby went through??..its not about temps in the GOM that intensify a storm..there are many other variables that come into play
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Quoting Bluestorm5:
It's way too early to be predicting a major in Gulf of Mexico. Haiti and Cuba is going to get hit by a tropical storm, if it didn't manages to reach hurricane strength, pretty good with the rain and winds. There will be mass flooding and mass deaths in both countries. After that, South Florida will get impacted and who know what's gonna happens after that? Wait and see, please...
Dunno bout the mass deaths in Cuba. They have, generallly speaking, had a better record of storm vigilance, and attention to timely evacuation. Haiti has the bigger problem.
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Quoting Catgypsy:
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.

Thanks Doc.



Possible according to one model..lets not sound the doom alarms just yet.....
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Quoting HurricaneDean07:

I believe the NHC needs to be upping the Intensity when Isaac gets through with the Islands... QUICKLY.
The Gulf Coast could easily get cuaght off-guard with the NHC forecasting a Category 1, and yet Isaac could go through RI in the Eastern Gulf and become a Category 3.


I believe they dont want to scare people away from the RNC.
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Sunday evening into Monday afternoon the lower Florida Keys could get blasted with 60 to 80 MPH wind gusts. Folks living in that area should get prepared now!
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Quoting HurricaneDean07:

I believe the NHC needs to be upping the Intensity when Isaac gets through with the Islands... QUICKLY.
The Gulf Coast could easily get cuaght off-guard with the NHC forecasting a Category 1, and yet Isaac could go through RI in the Eastern Gulf and become a Category 3.
We got to see what Isaac do with the islands first. NHC know what they are doing, trust me.
Member Since: August 1, 2011 Posts: 23 Comments: 7507
Quoting WxLogic:
Not bad with the Initialization:

12Z GFS


yep. looks like it has it in the right location.
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136. FOREX
Quoting yonzabam:
NHC says Isaac hits the Gulf coast on Wed morning as an 80 mph storm. Doc Masters predicts a landfall at 'approaching cat 3'.

Think the Doc is probably nearer the mark.


Anyone familiar with the topography of the part of Cuba Isaac will spin over? Will it run into the highest peaks or go West of them???
Member Since: August 17, 2011 Posts: 0 Comments: 846
Levi and I were talking about this on FB last night on the strange direct track NW through the Eastern GOM and why there wasnt more of a bend off to the North and NE later in the track. Well you can see the first run 12Z models starting to show that bend. Makes more sense to me.

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ULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE SAN JUAN PR
1053 AM AST FRI AUG 24 2012

THE NATIONAL WEATHER SERVICE IN SAN JUAN HAS ISSUED A

* FLASH FLOOD WARNING FOR...
THE FOLLOWING MUNICIPALITIES

IN PUERTO RICO
ARROYO
MAUNABO
PATILLAS

* UNTIL 145 PM AST

* AT 1048 AM AST...WEATHER DOPPLER RADAR INDICATED HEAVY TO MODERATE
SHOWER ACTIVITY ACROSS PORTIONS OF THE WARNED AREA. ADDITIONAL
SHOWERS AND THUNDERSTORMS...SOME OF THEM WITH EMBEDDED HEAVY
DOWNPOURS...ARE EXPECTED THROUGH THE EARLY AFTERNOON HOURS. THIS
RAINFALL IN ADDITION TO THE RAINFALL THAT HAS ALREADY OCCURRED...
WILL RESULT IN RAPID RISES ON SMALL STREAMS AND RIVERS. RESIDENTS
IN FLOOD PRONE AREAS SHOULD MOVE TO HIGHER GROUND IMMEDIATELY AND
NEVER TRY TO CROSS A FLOODED ROADWAY.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A FLASH FLOOD WARNING MEANS THAT FLOODING IS IMMINENT OR OCCURRING.
IF YOU ARE IN THE WARNING AREA MOVE TO HIGHER GROUND IMMEDIATELY.
RESIDENTS LIVING ALONG STREAMS AND CREEKS SHOULD TAKE IMMEDIATE
PRECAUTIONS TO PROTECT LIFE AND PROPERTY. DO NOT ATTEMPT TO CROSS
SWIFTLY FLOWING WATERS OR WATERS OF UNKNOWN DEPTH BY FOOT OR BY
AUTOMOBILE.



LAT...LON 1796 6606 1809 6606 1810 6606 1810 6602
1806 6600 1806 6596 1803 6592 1803 6589
1802 6588 1803 6587 1801 6585
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Accuweather...
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Member Since: August 1, 2011 Posts: 23 Comments: 7507
Quoting opal92nwf:
When was the last time someone saw a hurricane landfall in North Korea?


Great... now they are going to threaten the world with nukes to get aid again.
Member Since: May 31, 2007 Posts: 0 Comments: 1189
Not bad with the Initialization:

12Z GFS

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Quoting Bluestorm5:
It's way too early to be predicting a major in Gulf of Mexico. Haiti and Cuba is going to get hit by a tropical storm, if it didn't manages to reach hurricane strength, pretty good with the rain and winds. There will be mass flooding and mass deaths in both countries. After that, South Florida will get impacted and who know what's gonna happens after that? Wait and see, please...

I believe the NHC needs to be upping the Intensity when Isaac gets through with the Islands... QUICKLY.
The Gulf Coast could easily get cuaght off-guard with the NHC forecasting a Category 1, and yet Isaac could go through RI in the Eastern Gulf and become a Category 3.
Member Since: October 3, 2010 Posts: 40 Comments: 4129
Quoting oracle28:


I see the XTRP update has not changed its forecast.

Once this thing clears Cuba, the XTRP will start to become the model of choice.

you have to be trolling.

xtrp is not a model, never has been. all it does is tell you where the storm would go if it kept going on a straight line.
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Quoting Maineweatherguy20023:

YES


Well, so, it is moving according to specs...
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Quoting Bluestorm5:
It's way too early to be predicting a major in Gulf of Mexico. .


I agree..
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as I said I'll wait till recon flys in only then I would believe where the LLCOC is at
Member Since: June 13, 2009 Posts: 2 Comments: 9598
Quoting ProgressivePulse:
NHC sticking with the TVCN on the western side of the guidance included the map below.



I see the XTRP update has not changed its forecast.

Once this thing clears Cuba, the XTRP will start to become the model of choice.
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Quoting A4Guy:


Just means the chance of the center moving over us is basically zero...but if the storm crosses thru the Keys or the southern tip of the peninsula, we will certainly feel TS-force gusts in Miami-Dade and Broward counties.



will be on the dirty side of the storm also
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Quoting opal92nwf:
When was the last time someone saw a hurricane landfall in North Korea?


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Quoting GeoffreyWPB:


Look at the cone. T.S. Watches and Warnings for some of the Bahama Islands.
Yesterday we in Nassau were scheduled for 4-8 inches of accumulated rainfall over the next 3 days... Don't think Broward is "out of the water" yet...

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I live in homestead
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Quoting CybrTeddy:
I normally am not very bold with anything once it interacts with so much land like Isaac will be doing - but SST's where Isaac is heading for waters that are approaching 90 degrees in the Gulf of Mexico. I think it could become a Category 2 hurricane, perhaps more if it slows down.


Then again, it is intensity that usually trips me up.
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Quoting galvestonhurricane:


Good morning everyone! I'm not so sure they are wrong with the intensity forecast. Isaac is a very large storm with little vertical stacking. If it goes over land without being vertically stacked, it may take a significant amount of time for it to get its act together when it enters the GOM. In addition, there is the prospect of how close it comes to Florida.


Intensity is difficult to forecast. We are merely talking realistic potential here based upon conditions.
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Quoting Bluestorm5:
It's way too early to be predicting a major in Gulf of Mexico. Haiti and Cuba is going to get hit by a tropical storm, if it didn't manages to reach hurricane strength, pretty good with the rain and winds. There will be mass flooding and mass deaths in both countries. After that, South Florida will get impacted and who know what's gonna happens after that? Wait and see, please...


It is highly unlikely there will be "mass deaths" in Cuba.
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Member Since: August 6, 2011 Posts: 4 Comments: 33491
000
WTNT44 KNHC 241455
TCDAT4

TROPICAL STORM ISAAC DISCUSSION NUMBER 14
NWS NATIONAL HURRICANE CENTER MIAMI FL AL092012
1100 AM EDT FRI AUG 24 2012

RECONNAISSANCE AIRCRAFT DATA AND SATELLITE IMAGERY INDICATE THAT
ISAAC HAS BECOME BETTER ORGANIZED DURING THE PAST SEVERAL HOURS.
WHILE THE CIRCULATION CENTER REMAINS ELONGATED EAST-TO-WEST WITH
MULTIPLE EMBEDDED VORTICITY MAXIMA...THE LARGE CENTRAL AREA OF
LIGHT WINDS HAS SHRUNK AS THE STRONGEST WINDS MOVE CLOSER TO THE
CENTER. AN AIR FORCE RESERVE HURRICANE HUNTER AIRCRAFT REPORTED
66 KT FLIGHT-LEVEL WINDS AT 850 MB NORTHEAST OF THE CENTER...ALONG
WITH SFMR BIAS-CORRECTED WIND ESTIMATES NEAR 50 KT. BASED ON THESE
DATA...THE INITIAL INTENSITY IS INCREASED TO 50 KT.

THE 12Z POSITION USED A MEAN CENTER...WHICH RESULTED IN A SOUTHWARD
ADJUSTMENT. SINCE THEN...ISAAC APPEARS TO HAVE ACQUIRED A STRONGER
NORTHWARD COMPONENT OF MOTION...AND THE INITIAL MOTION IS A
SOMEWHAT UNCERTAIN 295/12. THE TRACK MODEL GUIDANCE IS IN GOOD
AGREEMENT THAT ISAAC SHOULD MOVED NORTHWESTWARD FOR THE NEXT 72
HR...STEERED BY THE SUBTROPICAL RIDGE OVER THE WESTERN ATLANTIC
TOWARD A WEAKNESS IN THE RIDGE OVER THE SOUTHEASTERN UNITED STATES.
THIS PART OF THE NEW FORECAST TRACK IS SHIFTED A LITTLE TO THE LEFT
OF THE PREVIOUS TRACK BASED ON THE INITIAL POSITION...AND LIES NEAR
THE CONSENSUS MODELS. AFTER 72 HR...THE SPREAD OF THE TRACK
GUIDANCE INCREASES DUE TO MODEL DISAGREEMENT ON THE EVOLUTION OF A
TROUGH OVER THE EASTERN UNITED STATES. THE ECMWF KEEPS MORE RIDGE
BETWEEN ISAAC AND THE TROUGH...WHICH RESULTS IN A NORTHWESTWARD
MOTION THROUGH DAY 5. THE GFS HAS A STRONGER TROUGH...WHICH
RESULTS IN A MORE NORTHWARD MOTION. THE GUIDANCE ENVELOPE HAS
SHIFTED A LITTLE EASTWARD AFTER 72 HR...AND THUS THE LATTER PORTION
OF THE NEW FORECAST TRACK IS ALSO ADJUSTED EASTWARD.

WHILE THE ORGANIZATION HAS IMPROVED...THE STRUCTURE OF ISAAC STILL
DOES NOT FAVOR RAPID INTENSIFICATION DESPITE A VERY FAVORABLE
UPPER-LEVEL WIND PATTERN. THE EARLY PART OF THE INTENSITY FORECAST
SHOWS A LITTLE MORE STRENGTHENING THAN EARLIER...AND IT IS POSSIBLE
THAT ISAAC COULD BE NEAR HURRICANE STRENGTH WHEN IT REACHES
HISPANIOLA. LAND INTERACTION WILL LIMIT THE INTENSITY FROM 24-48
HR...AND THIS PART OF THE FORECAST MAY NEED SOME ADJUSTMENT AFTER
IT IS SEEN WHAT STRUCTURE ISAAC HAS AFTER CROSSING HISPANIOLA.
ISAAC SHOULD STRENGTHEN OVER THE GULF OF MEXICO...WITH THE FORECAST
SHOWING THE CYCLONE BECOMING A HURRICANE BEFORE REACHING THE
NORTHERN GULF COAST.

IT IS IMPORTANT NOT TO FOCUS ON THE EXACT TRACK DUE TO THE
UNCERTAINTIES IN THE FORECAST AND THE FACT THAT ISAAC HAS A LARGE
AREA OF TROPICAL STORM FORCE WINDS ASSOCIATED WITH IT.


FORECAST POSITIONS AND MAX WINDS

INIT 24/1500Z 16.3N 70.8W 50 KT 60 MPH
12H 25/0000Z 17.4N 72.6W 55 KT 65 MPH
24H 25/1200Z 19.2N 75.1W 55 KT 65 MPH
36H 26/0000Z 20.9N 77.6W 50 KT 60 MPH...INLAND
48H 26/1200Z 22.3N 79.5W 45 KT 50 MPH...INLAND
72H 27/1200Z 25.0N 83.0W 55 KT 65 MPH...OVER WATER
96H 28/1200Z 28.0N 85.5W 65 KT 75 MPH
120H 29/1200Z 31.0N 86.5W 70 KT 80 MPH...INLAND

$$
FORECASTER BEVEN
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When was the last time someone saw a hurricane landfall in North Korea?
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Quoting tropicfreak:
Looks like as of lately he has taken a more NW movement instead of WNW.

Land interaction with Haiti may be keeping Isaac from wrapping around the convection and also pulling that slug of moisture over by Puerto Rico.



In the latest frame, you can see that "HWAAARGH" that's reminiscent of a guy bench-pressing at the gym, he's trying with all his might to get that heavy convection wrapped around, and he seems to finally be succeeding.

If this continues, the NHC forecast may not be nearly as conservative at 5 PM.
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111. VR46L
RIP Joyce...

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Jeff co-founded the Weather Underground in 1995 while working on his Ph.D. He flew with the NOAA Hurricane Hunters from 1986-1990.