Little change to Isaac, but storm poses a serious storm surge threat

By: Dr. Jeff Masters , 3:25 PM GMT on August 27, 2012

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Tropical Storm Isaac has changed little in strength or organization this morning, as the storm heads northwest at 14 mph towards the Central Gulf Coast. There are two hurricane hunter aircraft in the storm, and Isaac's central pressure held steady at 989 mb at the 8:30 am and 9:15 am center fixes. Top surface winds remain near 65 mph. Infrared and visible satellite loops show that Isaac is a very large storm, but isn't very symmetric. Heavy thunderstorm activity is lacking on the southeast side, where 10 knots of wind shear is driving dry air into the circulation. The center is surrounded by a ring of echoes now, which was not the case on Sunday. However, the echoes are weak. The 8:30 am center report from the Hurricane Hunters reported about half of a ragged eyewall, but the 9:15 am report did not mention any evidence of an eyewall. Isaac will have to form an eyewall in order to intensify significantly.


Figure 1. Morning satellite image of Isaac. Note the lack of heavy thunderstorm activity on the storm's southeast side, where dry air and wind shear are combining to interfere with development.

Isaac's rains
Isaac's heaviest rains have fallen along a swath from the east coast of Florida near West Palm Beach to the center of the state, just south of Orlando. West Palm Beach received 7.57" of rain from Isaac as of 10 am EDT this morning. A trained spotter in Western Boynton Beach reported 10" of rain from midnight to midnight Sunday. Heavy rains from Isaac are lingering over Cuba but have ended in Haiti and the Dominican Republic; flash floods in Haiti from Isaac's torrential rains killed at least nineteen, and two died in the Dominican Republic.


Figure 2. Radar-estimated rainfall from Melbourne, Florida radar shows that Isaac has dumped a wide swath of 3+ inches of rain (orange colors) across the state.

Latest model runs for Isaac
The latest set of 0Z and 06Z (8 pm and 2 am EDT) model runs are fairly unified taking Isaac ashore near Southeast Louisiana late Tuesday night or early Wednesday morning, but continue to show major differences in what happens after that. It is still uncertain if a trough of low pressure passing to the north of Isaac will be able to turn the storm due north, as the ECMWF model is predicting, or bypass the storm, allowing a more west-northwest motion into western Louisiana, like the GFS model is predicting. In either case, Isaac is likely to slow down as it approaches the coast, which will increase the damage potential fro m its wind, storm surge, and rains. The latest 8-day precipitation forecast from the GFS model calls for 10 - 20 inches of rain over much of Louisiana. The ECMWF model predicts that these heavy rains will fall more over Mississippi. It appears likely that Arkansas will see some heavy rains from Isaac late in the week, which would help put a dent in the exceptional drought conditions there.


Figure 3. Predicted precipitation for the 8-day period from 2 am Monday August 27 to 2 am Tuesday September 4, from the 2 am EDT August 27 run of the GFS model. This model is predicting a wide swath of 5 - 10 inches of rain (orange colors) will affect portions of Louisiana. Additional very heavy rains are predicted for the Midwest, as moisture from Isaac interacts with a cold front. Image credit: NOAA/NCEP.

Intensity forecast for Isaac
Isaac is currently crossing over a relatively cool eddy of water, which will keep intensification slow today. By tonight, the total heat content of the waters increases, which should aid intensification. Low wind shear of 10 knots or less is likely until landfall. An analysis of upper level winds from the University of Wisconsin CIMSS shows that upper-level outflow to the north is not as strong as yesterday, which should also slow intensification today. The models forecast the upper-level outflow should improve by Tuesday. A storm this large will have trouble undergoing rapid intensification, and Isaac's most likely intensity at landfall will be as a Category 1 hurricane, which is what most of the intensity models are forecasting.


Figure 4. Track of Hurricane Gustav of 2008, which followed a path very similar to that of Isaac's predicted path.

Storm surge forecast for Isaac
Storm surge is the primary damage threat from Isaac. Isaac is a huge storm, with tropical storm-force winds that extend out 205 miles from the center. For comparison, Hurricane Katrina at landfall had tropical storm-force winds that extended out 230 miles from its center. Isaac's large size will enable it to set a large area of the ocean into motion, which will generate a large storm surge once the storm approaches land on the Gulf Coast. Water levels at Shell Beach, Louisiana, just east of New Orleans, were already elevated by 1' this morning. Conversely, water levels have fallen by 2' this morning at St. Petersburg, Florida, where strong offshore winds due to Isaac's counter-clockwise circulation have carried water away from the coast. The latest 6:30 am EDT Integrated Kinetic Energy analysis from NOAA's Hurricane Research Division put the destructive potential of Isaac's winds near 0.6 on a scale of 0 to 6, but the destructive potential of Isaacs's storm surge was 2.1 on a scale of 0 to 6. I expect this destructive potential will rise above 3 by time Isaac makes landfall, making Isaac's storm surge similar to that generated by Category 2 Hurricane Gustav of 2008, which followed a path very similar to Isaac's predicted path. Gustav brought a storm surge characteristic of a Category 1 hurricane to New Orleans: 9.5' to Lake Borgne on the east side of the city. A higher Category 2-scale surge occurred along the south-central coast of Louisiana, and was 12.5' high in Black Bay, forty miles southeast of New Orleans. Recent model runs indicate Isaac may slow down to a forward speed under 5 mph on Tuesday evening and Wednesday morning, close to the coast. If Isaac is just offshore at this time, the coasts of Southeast Louisiana, Mississippi, Alabama, and the Florida Panhandle will be exposed to a large storm surge with battering waves for two high tide cycles. This sort of extending pounding will be capable of delivering more damage than the storm surge of Hurricane Gustav of 2008.

The affect of storm size and angle of approach on storm surge
A 2008 paper by Irish et al., The influence of storm size on hurricane surge, found that large storms like Isaac are capable to delivering a 30% larger storm surge to the coast than a smaller storm with the same maximum wind speeds. The angle with which the storm hit the coast is important, too--a storm moving due north or slightly east of north will deliver a storm surge about 10% greater than a storm moving NNW or NW. Consult our Storm Surge pages for detailed information on what the risk is for the coast. I expect that Isaac's storm surge will be about 30% higher than the typical surge one would expect based on the maximum wind speeds.

Isaac's storm surge will provide the first test of the newly-completed New Orleans levee system upgrade. In the wake of the disastrous storm surge flooding from Hurricane Katrina in 2005, Congress appropriated $14.5 billion to upgrade the New Orleans levee system to withstand a Category 3 hurricane storm surge. Katrina was a Category 3 storm at landfall, but the storm passed far enough to the east of the city that its storm surge was characteristic of a Category 1 - 2 storm at the places where the city's flood walls and levees failed. The new flood defenses were only partially completed in time for the arrival of Hurricane Gustav in 2008, which hit Central Louisiana as a Category 2 storm. Gustav brought a storm surge characteristic of a Category 1 hurricane to New Orleans: 9.5' to Lake Borgne on the east side of the city. Since that time, the imposing 2-mile long IHNC Flood Barrier has been completed to block off the funnel-shaped pair of canals on the east side of the city. I expect New Orleans' new flood defenses will be able to hold back Isaac's surge, but areas outside the levees are at risk of heavy storm surge damage.


Figure 5. A portion of New Orleans' new $14.5 billion dollar flood defenses, as taken from an Army Corps of Engineers map.

New Orleans flood defense info
Army Corps of Engineers map of the new flood defenses
Army Corps of Engineers video showing the flood defenses
New York Times article, Vast Defenses Now Shielding New Orleans

Invest 97L off the coast of Africa
A tropical wave (Invest 97L) is located in the Middle Atlantic, about 1050 miles west-northwest of the Cape Verde Islands. The storm has a modest amount of spin and heavy thunderstorms, and is under moderate wind shear. In their 8 am EDT Tropical Weather Outlook, NHC gave 97L a 30% chance of developing by Wednesday morning. None of the reliable models foresee that 97L will be a threat to the Lesser Antilles Islands, and high wind shear should begin to tear the disturbance apart on Tuesday.

Another tropical wave that moved off the coast of Africa on Sunday is located just south of the Cape Verde Islands. This disturbance is moving west at 10 - 15 mph, and could arrive in the Lesser Antilles around September 2. Several models develop the disturbance into a tropical depression late this week, and NHC is giving the disturbance a 10% chance of becoming a tropical depression by Wednesday morning.

Angela Fritz will have a new post here by 6 pm EDT. I'm in Atlanta to help out The Weather Channel with their on-air hurricane coverage, and will doing a few 3-minute tropical updates at 30 minutes past the hour between 2:30 - 7:30 pm EDT today.

Jeff Masters

Tropical Storm Isaac (chelina)
View from the north side of the Sunshine Skyway Bridge.
Tropical Storm Isaac
our street at noon today (seflagamma)
Aug 26, 2012: Isaac floods our street really bad. Now nearly 11
our street at noon today

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ESTIMATED MINIMUM CENTRAL PRESSURE 981 MB
MAX SUSTAINED WINDS 60 KT WITH GUSTS TO 75 KT.
50 KT....... 50NE 15SE 15SW 50NW.
34 KT.......150NE 150SE 80SW 180NW.
12 FT SEAS..180NE 180SE 180SW 150NW.
WINDS AND SEAS VARY GREATLY IN EACH QUADRANT. RADII IN NAUTICAL
MILES ARE THE LARGEST RADII EXPECTED ANYWHERE IN THAT QUADRANT.

Oh boy...
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TROPICAL STORM ISAAC FORECAST/ADVISORY NUMBER 27
NWS NATIONAL HURRICANE CENTER MIAMI FL AL092012
2100 UTC MON AUG 27 2012

CHANGES IN WATCHES AND WARNINGS WITH THIS ADVISORY...

THE HURRICANE WARNING FROM THE FLORIDA-ALABAMA BORDER TO DESTIN HAS
BEEN CHANGED TO A TROPICAL STORM WARNING.

SUMMARY OF WATCHES AND WARNINGS IN EFFECT...

A HURRICANE WARNING IS IN EFFECT FOR...
* EAST OF MORGAN CITY LOUISIANA TO THE ALABAMA-FLORIDA 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...
* FROM THE ALABAMA-FLORIDA BORDER TO THE AUCILLA RIVER
* INTRACOASTAL CITY TO MORGAN CITY LOUISIANA

A TROPICAL STORM WATCH IS IN EFFECT FOR...
* EAST OF SABINE PASS TO WEST OF INTRACOASTAL CITY 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 WITHIN 36 HOURS.

A TROPICAL STORM WATCH MEANS THAT TROPICAL STORM CONDITIONS ARE
POSSIBLE WITHIN THE WATCH AREA...GENERALLY WITHIN 48 HOURS.

TROPICAL STORM CENTER LOCATED NEAR 26.4N 86.2W AT 27/2100Z
POSITION ACCURATE WITHIN 15 NM

PRESENT MOVEMENT TOWARD THE NORTHWEST OR 305 DEGREES AT 10 KT

ESTIMATED MINIMUM CENTRAL PRESSURE 981 MB
MAX SUSTAINED WINDS 60 KT WITH GUSTS TO 75 KT.
50 KT....... 50NE 15SE 15SW 50NW.
34 KT.......150NE 150SE 80SW 180NW.
12 FT SEAS..180NE 180SE 180SW 150NW.
WINDS AND SEAS VARY GREATLY IN EACH QUADRANT. RADII IN NAUTICAL
MILES ARE THE LARGEST RADII EXPECTED ANYWHERE IN THAT QUADRANT.

REPEAT...CENTER LOCATED NEAR 26.4N 86.2W AT 27/2100Z
AT 27/1800Z CENTER WAS LOCATED NEAR 26.1N 85.9W

FORECAST VALID 28/0600Z 27.4N 87.5W
MAX WIND 70 KT...GUSTS 85 KT.
64 KT... 20NE 0SE 0SW 20NW.
50 KT... 60NE 20SE 20SW 60NW.
34 KT...165NE 150SE 80SW 180NW.

FORECAST VALID 28/1800Z 28.6N 89.0W
MAX WIND 80 KT...GUSTS 100 KT.
64 KT... 20NE 20SE 0SW 20NW.
50 KT... 60NE 50SE 30SW 60NW.
34 KT...180NE 150SE 80SW 180NW.

FORECAST VALID 29/0600Z 29.5N 90.0W...NEAR THE COAST
MAX WIND 85 KT...GUSTS 105 KT.
64 KT... 30NE 20SE 10SW 20NW.
50 KT... 60NE 60SE 40SW 60NW.
34 KT...180NE 150SE 80SW 150NW.

FORECAST VALID 29/1800Z 30.3N 90.7W...INLAND
MAX WIND 75 KT...GUSTS 90 KT.
50 KT... 60NE 60SE 40SW 40NW.
34 KT...180NE 150SE 80SW 110NW.

FORECAST VALID 30/1800Z 32.2N 91.8W...INLAND
MAX WIND 35 KT...GUSTS 45 KT.
34 KT... 60NE 130SE 30SW 40NW.

EXTENDED OUTLOOK. NOTE...ERRORS FOR TRACK HAVE AVERAGED NEAR 175 NM
ON DAY 4 AND 225 NM ON DAY 5...AND FOR INTENSITY NEAR 20 KT EACH DAY

OUTLOOK VALID 31/1800Z 35.9N 92.1W...INLAND
MAX WIND 25 KT...GUSTS 35 KT.

OUTLOOK VALID 01/1800Z 38.7N 89.3W...INLAND
MAX WIND 20 KT...GUSTS 30 KT.

REQUEST FOR 3 HOURLY SHIP REPORTS WITHIN 300 MILES OF 26.4N 86.2W

NEXT ADVISORY AT 28/0300Z

Not a hurricane ;/
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1507. divdog
Quoting kmanislander:


That is the only open path at the moment. The plains high is a blocker in that direction. Winds always lag a pressure drop.
My local nws mentions a developing trough over Ohio tenn valley as a key player. Best way to see it on water vapor or some other way
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Quoting Hoff511:


I drove through that too. NO FUN!
And they crazy south Florida drivers speed by you like nothing has happened....Geeez
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Isaac is only up to 70 mph.
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Who will post the Re-number...
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Patrap's watching us yay! plused #1485
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*clapping*
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1501. flcanes
Quoting TropicalAnalystwx13:
TROPICAL DEPRESSION NINE-E DISCUSSION NUMBER 1
NWS NATIONAL HURRICANE CENTER MIAMI FL EP092012
200 PM PDT MON AUG 27 2012

SATELLITE IMAGES SHOW THAT THE LOW PRESSURE SYSTEM LOCATED A FEW
HUNDRED MILES SOUTH-SOUTHWEST OF MANZANILLO MEXICO HAS DEVELOPED
ORGANIZED DEEP CONVECTION DURING THE LAST SEVERAL HOURS. IN
ADDITION...RECENT MICROWAVE DATA INDICATE THAT THE LOW-LEVEL CENTER
HAS BECOME WELL DEFINED. THEREFORE...THE LOW IS NOW CLASSIFIED AS A
TROPICAL DEPRESSION...THE NINTH OF THE EAST PACIFIC SEASON. THE
INITIAL INTENSITY IS 30 KT...THOUGH SOME ESTIMATES SUGGEST IT COULD
BE A LITTLE STRONGER. THE DEPRESSION IS FORECAST TO GAIN STRENGTH
DURING THE NEXT 3 TO 4 DAYS AS ENVIRONMENTAL CONDITIONS ARE
EXPECTED TO BE FAVORABLE. AFTER DAY 4...THE CYCLONE IS EXPECTED TO
MOVE OVER COOLER WATERS...AND THAT SHOULD END THE STRENGTHENING
TREND. THE OFFICIAL FORECAST IS IN THE MIDDLE OF THE INTENSITY
GUIDANCE ENVELOPE...IN CLOSEST AGREEMENT WITH LGEM.

THE DEPRESSION IS MOVING WEST-NORTHWESTWARD AT ABOUT 11 KT ON THE
SOUTH SIDE OF A MID-LEVEL RIDGE CENTERED OVER THE SOUTHWESTERN U.S.
THIS GENERAL MOTION SHOULD CONTINUE FOR ANOTHER DAY OR TWO AS THE
RIDGE REMAINS THE PRIMARY STEERING FEATURE. AFTER THAT...THE GLOBAL
MODELS SHOW THE RIDGE WEAKENING DUE TO THE COMBINED INFLUENCES OF
ATLANTIC TROPICAL STORM ISAAC MOVING OVER THE SOUTH-CENTRAL U.S.
AND A TROUGH MOVING TOWARD CALIFORNIA. THIS STEERING PATTERN SHOULD
CAUSE THE CYCLONE TO SLOW DOWN AND TURN NORTHWESTWARD. THE RIDGE
COULD REBUILD TO THE NORTHEAST OF THE SYSTEM BY THE END OF THE
FORECAST PERIOD CAUSING IT TO TURN BACK TO THE WEST-NORTHWEST. THE
OFFICIAL FORECAST IS NEAR THE CONSENSUS AIDS...TVCA AND TV15...AND
KEEPS THE CENTER OF THE CYCLONE WELL OFFSHORE OF THE COAST OF
MEXICO.

FORECAST POSITIONS AND MAX WINDS

INIT 27/2100Z 15.1N 107.0W 30 KT 35 MPH
12H 28/0600Z 15.6N 108.7W 40 KT 45 MPH
24H 28/1800Z 16.2N 110.6W 45 KT 50 MPH
36H 29/0600Z 16.6N 111.6W 50 KT 60 MPH
48H 29/1800Z 17.4N 112.2W 55 KT 65 MPH
72H 30/1800Z 19.0N 112.7W 60 KT 70 MPH
96H 31/1800Z 20.4N 113.7W 60 KT 70 MPH
120H 01/1800Z 22.0N 117.5W 55 KT 65 MPH

$$
FORECASTER CANGIALOSI
ILLENEA YES will be here
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Quoting Bluestorm5:


Pressure dropped 3-4 mb in past hour. Went from 985 mb to 981 in one pass. We got hurricane force winds to SW of Isaac's center and we got eye forming. Isaac is technically undergoing RI.

Didn't we have a quick pressure drop to 990 mb last night...and we thought RI was starting...when in fact it seemed like a drop in the bucket after he only went to 65 mph winds?

Last night I was wondering if he was shrinking in size. I say nay...he is better modeled as a bigger storm with a more lax pressure gradient...so the pressure drops may perhaps push him to 70 mph...
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Quoting flcanes:

lol, will next year be females again?

Probably lol, I think big ones next year will be Erin, Gabrielle, Karen, and Melissa.
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1498. bappit
#1458 Water vapor showing the warming above the eye, too.
Member Since: Posts: Comments:
FORECAST POSITIONS AND MAX WINDS

INIT 27/2100Z 15.1N 107.0W 30 KT 35 MPH
12H 28/0600Z 15.6N 108.7W 40 KT 45 MPH
24H 28/1800Z 16.2N 110.6W 45 KT 50 MPH
36H 29/0600Z 16.6N 111.6W 50 KT 60 MPH
48H 29/1800Z 17.4N 112.2W 55 KT 65 MPH
72H 30/1800Z 19.0N 112.7W 60 KT 70 MPH
96H 31/1800Z 20.4N 113.7W 60 KT 70 MPH
120H 01/1800Z 22.0N 117.5W 55 KT 65 MPH


TD Nine-E has form FYI.

Give it a little love <3
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Quoting Wiiilbur:
Maybe some of you who are more experienced than me can help me understand something. According to the Cumulative Wind Map, all of south, southeast and southwest Florida are shown to have experienced winds in excess of tropical storm level (>39 mph). However, looking at the past history of the storm, with a NHC intensity of 60 mph as it passed Key West, I can't find a single National Weather Service station or offshore buoy that shows sustained winds that reached tropical storm intensity in any part of Florida, let alone anywhere near 60 mph. Maybe someone can help clarify this for me.


I'm guessing wind gust of TS strength vs sustained winds of TS strength is the difference
Member Since: Posts: Comments:
1494. Hoff511
Quoting FrancesJeanne:
Port St. Lucie this afternoon. So glad to see this band finally moving offshore - crossing my fingers that it keeps right on going; enough is enough already!


I drove through that too. NO FUN!
Member Since: Posts: Comments:
Quoting sunlinepr:
Intensity forecast....

No more than 90mph....

Knots, 90 knots is about 105 mph
Member Since: Posts: Comments:
1492. flcanes
Quoting hurricanehanna:
...brace the blog for the 4pm update...will he, or won't he ?

will he or will he not, that is the question
interpretation on hamlet
Member Since: Posts: Comments:
TROPICAL DEPRESSION NINE-E DISCUSSION NUMBER 1
NWS NATIONAL HURRICANE CENTER MIAMI FL EP092012
200 PM PDT MON AUG 27 2012

SATELLITE IMAGES SHOW THAT THE LOW PRESSURE SYSTEM LOCATED A FEW
HUNDRED MILES SOUTH-SOUTHWEST OF MANZANILLO MEXICO HAS DEVELOPED
ORGANIZED DEEP CONVECTION DURING THE LAST SEVERAL HOURS. IN
ADDITION...RECENT MICROWAVE DATA INDICATE THAT THE LOW-LEVEL CENTER
HAS BECOME WELL DEFINED. THEREFORE...THE LOW IS NOW CLASSIFIED AS A
TROPICAL DEPRESSION...THE NINTH OF THE EAST PACIFIC SEASON. THE
INITIAL INTENSITY IS 30 KT...THOUGH SOME ESTIMATES SUGGEST IT COULD
BE A LITTLE STRONGER. THE DEPRESSION IS FORECAST TO GAIN STRENGTH
DURING THE NEXT 3 TO 4 DAYS AS ENVIRONMENTAL CONDITIONS ARE
EXPECTED TO BE FAVORABLE. AFTER DAY 4...THE CYCLONE IS EXPECTED TO
MOVE OVER COOLER WATERS...AND THAT SHOULD END THE STRENGTHENING
TREND. THE OFFICIAL FORECAST IS IN THE MIDDLE OF THE INTENSITY
GUIDANCE ENVELOPE...IN CLOSEST AGREEMENT WITH LGEM.

THE DEPRESSION IS MOVING WEST-NORTHWESTWARD AT ABOUT 11 KT ON THE
SOUTH SIDE OF A MID-LEVEL RIDGE CENTERED OVER THE SOUTHWESTERN U.S.
THIS GENERAL MOTION SHOULD CONTINUE FOR ANOTHER DAY OR TWO AS THE
RIDGE REMAINS THE PRIMARY STEERING FEATURE. AFTER THAT...THE GLOBAL
MODELS SHOW THE RIDGE WEAKENING DUE TO THE COMBINED INFLUENCES OF
ATLANTIC TROPICAL STORM ISAAC MOVING OVER THE SOUTH-CENTRAL U.S.
AND A TROUGH MOVING TOWARD CALIFORNIA. THIS STEERING PATTERN SHOULD
CAUSE THE CYCLONE TO SLOW DOWN AND TURN NORTHWESTWARD. THE RIDGE
COULD REBUILD TO THE NORTHEAST OF THE SYSTEM BY THE END OF THE
FORECAST PERIOD CAUSING IT TO TURN BACK TO THE WEST-NORTHWEST. THE
OFFICIAL FORECAST IS NEAR THE CONSENSUS AIDS...TVCA AND TV15...AND
KEEPS THE CENTER OF THE CYCLONE WELL OFFSHORE OF THE COAST OF
MEXICO.

FORECAST POSITIONS AND MAX WINDS

INIT 27/2100Z 15.1N 107.0W 30 KT 35 MPH
12H 28/0600Z 15.6N 108.7W 40 KT 45 MPH
24H 28/1800Z 16.2N 110.6W 45 KT 50 MPH
36H 29/0600Z 16.6N 111.6W 50 KT 60 MPH
48H 29/1800Z 17.4N 112.2W 55 KT 65 MPH
72H 30/1800Z 19.0N 112.7W 60 KT 70 MPH
96H 31/1800Z 20.4N 113.7W 60 KT 70 MPH
120H 01/1800Z 22.0N 117.5W 55 KT 65 MPH

$$
FORECASTER CANGIALOSI
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Quoting NCHurricane2009:

Makes sense...I wonder if he's ever gonna become a hurricane at all...

He's going to be one per recon.
Member Since: Posts: Comments:
BULLETIN
TROPICAL DEPRESSION NINE-E ADVISORY NUMBER 1
NWS NATIONAL HURRICANE CENTER MIAMI FL EP092012
200 PM PDT MON AUG 27 2012

...TROPICAL DEPRESSION FORMS WELL SOUTH OF MEXICO...


SUMMARY OF 200 PM PDT...2100 UTC...INFORMATION
----------------------------------------------
LOCATION...15.1N 107.0W
ABOUT 325 MI...520 KM SW OF MANZANILLO MEXICO
MAXIMUM SUSTAINED WINDS...35 MPH...55 KM/H
PRESENT MOVEMENT...WNW OR 290 DEGREES AT 13 MPH...20 KM/H
MINIMUM CENTRAL PRESSURE...1006 MB...29.71 INCHES
Member Since: Posts: Comments:
BULLETIN
TROPICAL DEPRESSION NINE-E ADVISORY NUMBER 1
NWS NATIONAL HURRICANE CENTER MIAMI FL EP092012
200 PM PDT MON AUG 27 2012

...TROPICAL DEPRESSION FORMS WELL SOUTH OF MEXICO...


SUMMARY OF 200 PM PDT...2100 UTC...INFORMATION
----------------------------------------------
LOCATION...15.1N 107.0W
ABOUT 325 MI...520 KM SW OF MANZANILLO MEXICO
MAXIMUM SUSTAINED WINDS...35 MPH...55 KM/H
PRESENT MOVEMENT...WNW OR 290 DEGREES AT 13 MPH...20 KM/H
MINIMUM CENTRAL PRESSURE...1006 MB...29.71 INCHES


WATCHES AND WARNINGS
--------------------
THERE ARE NO COASTAL WATCHES OR WARNINGS IN EFFECT.


DISCUSSION AND 48-HOUR OUTLOOK
------------------------------
AT 200 PM PDT...2100 UTC...THE CENTER OF TROPICAL DEPRESSION NINE-E
WAS LOCATED NEAR LATITUDE 15.1 NORTH...LONGITUDE 107.0 WEST. THE
DEPRESSION IS MOVING TOWARD THE WEST-NORTHWEST NEAR 12 MPH...19
KM/H. THIS GENERAL HEADING WITH A SLIGHT REDUCTION IN FORWARD SPEED
IS EXPECTED OVER THE NEXT COUPLE OF DAYS.

MAXIMUM SUSTAINED WINDS ARE NEAR 35 MPH...55 KM/H...WITH HIGHER
GUSTS. SOME STRENGTHENING IS FORECAST DURING THE NEXT 48
HOURS...AND THE DEPRESSION COULD BECOME A TROPICAL STORM BY
TONIGHT.

ESTIMATED MINIMUM CENTRAL PRESSURE IS 1006 MB...29.71 INCHES.


HAZARDS AFFECTING LAND
----------------------
NONE.


NEXT ADVISORY
-------------
NEXT COMPLETE ADVISORY...800 PM PDT.

$$
FORECASTER CANGIALOSI
Member Since: Posts: Comments:
000
WTPZ34 KNHC 272042
TCPEP4

BULLETIN
TROPICAL DEPRESSION NINE-E ADVISORY NUMBER 1
NWS NATIONAL HURRICANE CENTER MIAMI FL EP092012
200 PM PDT MON AUG 27 2012

...TROPICAL DEPRESSION FORMS WELL SOUTH OF MEXICO...


SUMMARY OF 200 PM PDT...2100 UTC...INFORMATION
----------------------------------------------
LOCATION...15.1N 107.0W
ABOUT 325 MI...520 KM SW OF MANZANILLO MEXICO
MAXIMUM SUSTAINED WINDS...35 MPH...55 KM/H
PRESENT MOVEMENT...WNW OR 290 DEGREES AT 13 MPH...20 KM/H
MINIMUM CENTRAL PRESSURE...1006 MB...29.71 INCHES


WATCHES AND WARNINGS
--------------------
THERE ARE NO COASTAL WATCHES OR WARNINGS IN EFFECT.


DISCUSSION AND 48-HOUR OUTLOOK
------------------------------
AT 200 PM PDT...2100 UTC...THE CENTER OF TROPICAL DEPRESSION NINE-E
WAS LOCATED NEAR LATITUDE 15.1 NORTH...LONGITUDE 107.0 WEST. THE
DEPRESSION IS MOVING TOWARD THE WEST-NORTHWEST NEAR 12 MPH...19
KM/H. THIS GENERAL HEADING WITH A SLIGHT REDUCTION IN FORWARD SPEED
IS EXPECTED OVER THE NEXT COUPLE OF DAYS.

MAXIMUM SUSTAINED WINDS ARE NEAR 35 MPH...55 KM/H...WITH HIGHER
GUSTS. SOME STRENGTHENING IS FORECAST DURING THE NEXT 48
HOURS...AND THE DEPRESSION COULD BECOME A TROPICAL STORM BY
TONIGHT.

ESTIMATED MINIMUM CENTRAL PRESSURE IS 1006 MB...29.71 INCHES.


HAZARDS AFFECTING LAND
----------------------
NONE.


NEXT ADVISORY
-------------
NEXT COMPLETE ADVISORY...800 PM PDT.

$$
FORECASTER CANGIALOSI

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Intensity forecast....

Not more than 90mph....

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Quoting catastropheadjuster:
I have been hearing the trains coming from the state docks, downtown Mobile,Al all day, sounds like right before Katrina. There all heading North and loaded to the gill. You can hear the motors in a strain. this should tell folks they need to listen.

Sheri
They would keep the loaded ones there. They are to heavy to get knocked around by the lil 35mph winds we are going to get. And as for tides, they shouldn't be more than 5' surge here I wouldn't think.
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Quoting Thing342:
I wonder what the blog's reaction would be if the NHC doesn't make Isaac a hurricane.


Pitchforks and Tourches
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1482. flcanes
Quoting Felix2007:

Well last year was female names (Irene, Katia, Ophelia, Rina) so now it's the guy's turn.

lol, will next year be females again?
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...brace the blog for the 4pm update...will he, or won't he ?
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Quoting FrancesJeanne:
Port St. Lucie this afternoon. So glad to see this band finally moving offshore - crossing my fingers that it keeps right on going; enough is enough already!
Thats what I was driving in! So glad to be home now!
Member Since: August 18, 2008 Posts: 0 Comments: 467
Quoting flcanes:

will beryl be upgraded post-season?

No.
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1478. Hoff511
Quoting TreasureCoastFl:
yup. Been a crazy day. Very flooded here. Streets are like rivers. Hopefully is done here but weatherman said something about possible bands moving back up from Miami later tonight?


yeah, not pretty, I drove home from work in Ft. Pierce and almost all of 25th street was under water.
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1477. robj144
Quoting PalmBeachWeather:
Hoff......I know what you mean... The thunder was a very low deep bass sound. Kind of like a kids bass stereo in a car. It shakes everything


That's what I heard the entire night last night.
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Quoting divdog:
Squeezing in between the high to east and the high to the west providing a path of least resistance for the storm to follow.? Big storm winds waiting to catch up.


That is the only open path at the moment. The plains high is a blocker in that direction. Winds always lag a pressure drop.
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929. Neapolitan 7:13 PM GMT on August 27, 2012 +106

#winning
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Quoting RitaEvac:


Paranoia


I think Texas is going to get a lot of......heat.
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I wonder what the blog's reaction would be if the NHC doesn't make Isaac a hurricane.
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1472. LargoFl
Member Since: August 6, 2011 Posts: 4 Comments: 36905
dont forgot hurricane dolly of 08 was a ts 30 hours before landfall and made landfall as a cat 2. isaac has the same amount of time. lets see how strong he gets
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Quoting MississippiWx:


Nea is a great blogger and contributor here. Very well-respected and always level-headed. Great to have him here.


I agree with you assessment of Neapolitan, but would like to let you no that she is a woman, and not a man. When in doubt of gender, it helps to use the combination pronoun he/she or "they".
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Quoting NCHurricane2009:

Makes sense...I wonder if he's ever gonna become a hurricane at all...


He thinks "yes" this evening.
Member Since: September 16, 2007 Posts: 0 Comments: 6111
Quoting snotly:
What we here in the vernacular call a tropospheric vortex inducing a Burnuli effect in conjunction with the Coriolis effect due to equalization of pressure caused by the evaporation transport of heat above 850 millibars layer inducing a relative wind speed of or above 3308.1 centimeters per second.



Very sciencey, snotly.
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Quoting trHUrrIXC5MMX:




why are the windbarbs facing a different direction in your image compared to this one? strange
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Quoting Sfloridacat5:
Dr Masters just now on TWC - "not going to be a cat 2 today or tomorrow."


Good. :)
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Quoting Sirena7cs:


We do. Even those of us on the West Coast do. Looks like it's coming for us next!
It's probably my imagination, or maybe a visual illusion when juxtiposed next to Issac, but it looks like it's beginging to develop it's own spin in the opposite direction.

If it is spinning in the opposite direction, either the east coast of Florida has been transported a few thousand miles to the south, it is just an illusion, or a never-before-seen feature of meteorology is happening before our eyes. I'm going with #2.
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Quoting Neapolitan:
I'm not the blog police, and far be it from me to stomp on anyone's fun, but I personally find the repeated jokes about Stephanie Abrams' body to be tasteless and disrespectful. I understand that some may not like her, and that's their choice. I also understand that some may find her attractive. That, too, is their choice. But the woman is a professional, not some bimbo posing for the cover of Maxim; she's got degrees in meteorology and geography (along with a minor in mathematics, fer cryin' out loud). As often as met students in this forum talk about how difficult those courses are, I'd think Ms Abrams would deserve at least here to be talked about for what she's accomplished more than the physical attributes gifted to her by her DNA. Not to mention: there aren't just hormonal males frequenting this forum. So can you guys maybe save the female body worship for WU mails or your own blogs? Please?
plus 105 for one post, nice post Nea.
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Quoting Sfloridacat5:
Dr Masters just now on TWC - "not going to be a cat 2 today or tomorrow."

Makes sense...I wonder if he's ever gonna become a hurricane at all...
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Quoting Hoff511:
Hey Everyone, on topic but a little bit of a sidetrack. I know storms, but just experienced in Port Saint Lucie, FL thunder and lightning like never before. It was a weird flash, not a bolt, followed by what could only be described as multiple sonic booms occurring simultaneously. To the point of shaking my patio doors. Not thinking conspiracies or anything crazy just wondering if anyone else is aware of or has experienced this phenomenon. I have been through plenty of storms and rolling thunder but this is beyond that exponentially.
Hoff......I know what you mean... The thunder was a very low deep bass sound. Kind of like a kids bass stereo in a car. It shakes everything
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1461. flcanes
Quoting allancalderini:
Btw only male names have become hurricanes until know this year in the Atlantic (Chris,Ernesto,Gordon and probably Isaac).

will beryl be upgraded post-season?
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Port St. Lucie this afternoon. So glad to see this band finally moving offshore - crossing my fingers that it keeps right on going; enough is enough already!
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Quoting allancalderini:
Btw only male names have become hurricanes until know this year in the Atlantic (Chris,Ernesto,Gordon and probably Isaac).

Well last year was female names (Irene, Katia, Ophelia, Rina) so now it's the guy's turn.
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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.

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