Tropical Depression Isaac:

[sambucol]

Are we completely in the clear with Isaac?

[biggerbyte]

Completely out of the woods.. No! One is never that until a live system is dead over land. Again, things change daily. Watch for some possible twists and Isaac moves closer to the north central Gulf shore. I'm not saying anymore about that for now.

[unome]

Are we completely in the clear with Isaac?

hi Sam - I'm not a pro met (but I have slept in a Holiday Inn , here's your 7-day forecast for Baytown http://forecast.weather.gov/MapClick.ph ... X%2C%20USA

conversely, here's the 7-day forecast for Key West http://forecast.weather.gov/MapClick.ph ... 0%2C%20USA

also, here's the 7-day forecast for Pensacola Airport http://forecast.weather.gov/MapClick.ph ... L%2C%20USA

[srainhoutx]

Product: Air Force Vortex Message (URNT12 KNHC)
Transmitted: 24th day of the month at 22:47Z
Corrected: This observation corrected a previous observation.
Aircraft: Air Force Aircraft (Last 3 digits of the tail number are 300)
Storm Number & Year: 09L in 2012
Storm Name: Isaac (flight in the North Atlantic basin)
Mission Number: 12
Observation Number: 14
A. Time of Center Fix: 24th day of the month at 22:27:20Z
B. Center Fix Coordinates: 17°03'N 71°50'W (17.05N 71.8333W)
B. Center Fix Location: 108 miles (174 km) to the SSE (162°) from Port-au-Prince, Haiti.
C. Minimum Height at Standard Level: 1,374m (4,508ft) at 850mb
D. Estimated (by SFMR or visually) Maximum Surface Wind: 57kts (~ 65.6mph)
E. Location of the Estimated Maximum Surface Wind: 43 nautical miles (49 statute miles) to the NE (45°) of center fix
F. Maximum Flight Level Wind Inbound: From 144° at 60kts (From the SE at ~ 69.0mph)
G. Location of Maximum Flight Level Wind Inbound: 74 nautical miles (85 statute miles) to the NE (52°) of center fix
H. Minimum Sea Level Pressure: 993mb (29.32 inHg)
I. Maximum Flight Level Temp & Pressure Altitude Outside Eye: 14°C (57°F) at a pressure alt. of 1,524m (5,000ft)
J. Maximum Flight Level Temp & Pressure Altitude Inside Eye: 18°C (64°F) at a pressure alt. of 1,525m (5,003ft)
K. Dewpoint Temp (collected at same location as temp inside eye): 18°C (64°F)
K. Sea Surface Temp (collected at same location as temp inside eye): Not Available
L. Eye Character: Not Available
M. Eye Shape: Not Available
N. Fix Determined By: Penetration, Wind, Pressure and Temperature
N. Fix Levels (sfc and flt lvl centers are within 5nm of each other): Surface and 850mb
O. Navigation Fix Accuracy: 0.02 nautical miles
O. Meteorological Accuracy: 3 nautical miles
Remarks Section:
Maximum Flight Level Wind: 64kts (~ 73.6mph) in the east quadrant at 21:41:30Z
Maximum Flight Level Temp: 19°C (66°F) which was observed 6 nautical miles to the N (9°) from the flight level center

[srainhoutx]

Product: Air Force Vortex Message (URNT12 KNHC)
Transmitted: 24th day of the month at 23:28Z
Aircraft: Air Force Aircraft (Last 3 digits of the tail number are 300)
Storm Number & Year: 09L in 2012
Storm Name: Isaac (flight in the North Atlantic basin)
Mission Number: 12
Observation Number: 18
A. Time of Center Fix: 24th day of the month at 23:16:20Z
B. Center Fix Coordinates: 17°00'N 71°57'W (17.N 71.95W) (View map)
B. Center Fix Location: 109 miles (176 km) to the SSE (167°) from Port-au-Prince, Haiti.
C. Minimum Height at Standard Level: 1,375m (4,511ft) at 850mb
D. Estimated (by SFMR or visually) Maximum Surface Wind: 36kts (~ 41.4mph)
E. Location of the Estimated Maximum Surface Wind: 31 nautical miles (36 statute miles) to the ESE (123°) of center fix
F. Maximum Flight Level Wind Inbound: From 206° at 44kts (From the SSW at ~ 50.6mph)
G. Location of Maximum Flight Level Wind Inbound: 41 nautical miles (47 statute miles) to the SE (126°) of center fix
H. Minimum Sea Level Pressure: 994mb (29.35 inHg)
I. Maximum Flight Level Temp & Pressure Altitude Outside Eye: 17°C (63°F) at a pressure alt. of 1,518m (4,980ft)
J. Maximum Flight Level Temp & Pressure Altitude Inside Eye: 18°C (64°F) at a pressure alt. of 1,526m (5,007ft)
K. Dewpoint Temp (collected at same location as temp inside eye): 17°C (63°F)
K. Sea Surface Temp (collected at same location as temp inside eye): Not Available
L. Eye Character: Not Available
M. Eye Shape: Not Available
N. Fix Determined By: Penetration, Wind, Pressure and Temperature
N. Fix Levels (sfc and flt lvl centers are within 5nm of each other): Surface and 850mb
O. Navigation Fix Accuracy: 0.02 nautical miles
O. Meteorological Accuracy: 2 nautical miles
Remarks Section:
Maximum Flight Level Wind: 64kts (~ 73.6mph) in the east quadrant at 21:41:30Z
Maximum Flight Level Temp: 18°C (64°F) which was observed 12 nautical miles (14 statute miles) to the ESE (109°) from the flight level center

[srainhoutx]

BULLETIN
TROPICAL STORM ISAAC INTERMEDIATE ADVISORY NUMBER 15A
NWS NATIONAL HURRICANE CENTER MIAMI FL AL092012
800 PM EDT FRI AUG 24 2012

...ISAAC TEMPORARILY SLOWS DOWN...BUT STILL EXPECTED TO MAKE
LANDFALL IN HAITI TONIGHT...


SUMMARY OF 800 PM EDT...0000 UTC...INFORMATION
----------------------------------------------
LOCATION...17.3N 72.0W
ABOUT 90 MI...145 KM SSE OF PORT AU PRINCE HAITI
ABOUT 270 MI...440 KM SE OF GUANTANAMO CUBA
MAXIMUM SUSTAINED WINDS...65 MPH...100 KM/H
PRESENT MOVEMENT...NW OR 315 DEGREES AT 10 MPH...17 KM/H
MINIMUM CENTRAL PRESSURE...992 MB...29.29 INCHES


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

NONE.

SUMMARY OF WATCHES AND WARNINGS IN EFFECT...

A HURRICANE WATCH IS IN EFFECT FOR...
* HAITI

A TROPICAL STORM WARNING IS IN EFFECT FOR...
* DOMINICAN REPUBLIC
* HAITI
* CUBAN PROVINCES OF CIEGO DE AVILA...SANCTI SPIRITUS...VILLA
CLARA...CAMAGUEY...LAS TUNAS...GRANMA...HOLGUIN...SANTIAGO DE
CUBA...AND GUANTANAMO
* ANDROS ISLAND
* THE CENTRAL BAHAMAS INCLUDING CAT ISLAND...THE EXUMAS...LONG
ISLAND...RUM CAY...AND SAN SALVADOR
* SOUTHEASTERN BAHAMAS INCLUDING THE ACKLINS...CROOKED ISLAND...LONG
CAY...THE INAGUAS...MAYAGUANA...AND THE RAGGED ISLANDS
* TURKS AND CAICOS ISLANDS

A TROPICAL STORM WATCH IS IN EFFECT FOR...
* CUBAN PROVINCES OF MATANZAS AND CIENFUEGOS
* JAMAICA
* THE NORTHWESTERN BAHAMAS...INCLUDING THE ABACOS...BERRY ISLANDS...
BIMINI...ELEUTHERA...GRAND BAHAMA ISLAND...AND NEW PROVIDENCE.
* THE FLORIDA KEYS INCLUDING THE DRY TORTUGAS
* THE FLORIDA EAST COAST SOUTH OF JUPITER INLET
* THE FLORIDA WEST COAST SOUTH OF BONITA BEACH
* FLORIDA BAY AND LAKE OKEECHOBEE

A HURRICANE WATCH MEANS THAT HURRICANE CONDITIONS ARE POSSIBLE
WITHIN THE WATCH AREA...IN THIS CASE WITHIN THE NEXT 24 TO 36 HOURS.

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.

INTERESTS IN THE REMAINDER OF CUBA AND THE REMAINDER OF THE FLORIDA
PENINSULA SHOULD MONITOR THE PROGRESS OF ISAAC.

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


DISCUSSION AND 48-HOUR OUTLOOK
------------------------------
AT 800 PM EDT...0000 UTC...THE CENTER OF TROPICAL STORM ISAAC WAS
LOCATED NEAR LATITUDE 17.3 NORTH...LONGITUDE 72.0 WEST. ISAAC IS
MOVING TOWARD THE NORTHWEST NEAR 10 MPH...17 KM/H...BUT IS EXPECTED
TO RESUME A FASTER FORWARD SPEED TOWARD THE NORTHWEST TONIGHT
THROUGH SUNDAY. ON THE FORECAST TRACK...THE CENTER OF ISAAC SHOULD
MAKE LANDFALL IN HAITI TONIGHT...MOVE NEAR OR OVER SOUTHEASTERN
CUBA ON SATURDAY...MOVE NEAR OR OVER CENTRAL CUBA SATURDAY NIGHT...
AND APPROACH THE FLORIDA KEYS ON SUNDAY.

REPORTS FROM AN AIR FORCE RESERVE HURRICANE HUNTER AIRCRAFT INDICATE
THAT MAXIMUM SUSTAINED WINDS REMAIN NEAR 65 MPH...100 KM/H...WITH
HIGHER GUSTS. LITTLE CHANGE IN STRENGTH IS LIKELY BEFORE
LANDFALL...FOLLOWED BY SOME WEAKENING AS THE CENTER CROSSES
HAITI AND SOUTHEASTERN CUBA.

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

THE MINIMUM CENTRAL PRESSURE REPORTED BY THE HURRICANE HUNTER
AIRCRAFT IS 992 MB...29.29 INCHES.


HAZARDS AFFECTING LAND
----------------------
RAINFALL...TOTAL RAINFALL ACCUMULATIONS OF 8 TO 12 INCHES...WITH
MAXIMUM AMOUNTS OF 20 INCHES...ARE POSSIBLE OVER HISPANIOLA. THESE
RAINS COULD CAUSE LIFE-THREATENING FLASH FLOODS AND MUD SLIDES.
TOTAL RAIN ACCUMULATIONS OF 4 TO 8 INCHES...WITH MAXIMUM AMOUNTS OF
12 INCHES...ARE POSSIBLE ACROSS CENTRAL AND EASTERN CUBA...AS WELL
AS JAMAICA. TOTAL RAIN ACCUMULATIONS OF 2 TO 4 INCHES...WITH
MAXIMUM AMOUNTS OF 6 INCHES ARE EXPECTED OVER PUERTO RICO. TOTAL
RAIN ACCUMULATIONS OF 2 TO 4 INCHES ARE POSSIBLE OVER THE
SOUTHEASTERN AND CENTRAL BAHAMAS. RAIN ACCUMULATIONS OF 4 TO 8
INCHES...WITH MAXIMUM AMOUNTS OF 12 INCHES...ARE POSSIBLE OVER THE
FLORIDA KEYS AND THE SOUTHERN FLORIDA PENINSULA.

WIND...TROPICAL STORM CONDITIONS ARE SPREADING OVER PORTIONS OF THE
DOMINICAN REPUBLIC AND HAITI...WITH HURRICANE CONDITIONS POSSIBLE.
TROPICAL STORM CONDITIONS ARE EXPECTED OVER THE SOUTHEASTERN
BAHAMAS AND THE TURKS AND CAICOS ISLANDS TONIGHT...ARE EXPECTED
OVER THE CENTRAL BAHAMAS BY SATURDAY OR SATURDAY NIGHT...AND ARE
EXPECTED OVER ANDROS ISLAND BY SUNDAY. TROPICAL STORM CONDITIONS
ARE EXPECTED OVER EASTERN CUBA BY TONIGHT AND OVER CENTRAL CUBA BY
SATURDAY OR SATURDAY NIGHT. TROPICAL STORM CONDITIONS COULD REACH
NORTHWESTERN CUBA AND THE NORTHWESTERN BAHAMAS BY SATURDAY NIGHT OR
SUNDAY...AND SOUTH FLORIDA AND THE FLORIDA KEYS ON SUNDAY.

STORM SURGE...A STORM SURGE WILL RAISE WATER LEVELS BY AS MUCH AS 1
TO 3 FEET ABOVE NORMAL TIDE LEVELS IN AREAS OF ONSHORE WINDS IN THE
TROPICAL STORM WARNING AREAS. NEAR THE COAST...THE SURGE WILL BE
ACCOMPANIED BY DANGEROUS WAVES.

SURF...DANGEROUS SURF AND RIP CURRENT CONDITIONS WILL AFFECT PUERTO
RICO...HISPANIOLA...THE SOUTHEASTERN AND CENTRAL BAHAMAS...THE
TURKS AND CAICOS...AND EASTERN AND CENTRAL CUBA DURING THE NEXT
COUPLE OF DAYS. PLEASE CONSULT PRODUCTS FROM YOUR LOCAL WEATHER
OFFICE FOR MORE INFORMATION.


NEXT ADVISORY
-------------
NEXT COMPLETE ADVISORY...1100 PM EDT.

$$
FORECASTER STEWART

[srainhoutx]

For what it's worth, the 18Z HWRF suggests a SE Louisiana/MS landfall.

[sambucol]

That would be bad for New Orleans.

[srainhoutx]

18Z GFDL suggests near theMS/AL Border...Mobile perhaps...

[srainhoutx]

Isaac is beginning to develop some convection near the center. As we near D Max in the early morning hours, we may see a core develop if the trends continue.

[jeff]

For what it's worth, the 18Z HWRF suggests a SE Louisiana/MS landfall.

18Z GfS and 18Z GFDL are west also. 00Z NAM looks well west. All in that pesky trough digging into the PAC NW and the downstream ridge. Models are quicker to shear than trough out with the CONUS pattern more zonal than amplified giving more ridging north of Isaac. Saw somewhat of the same thing last night only for everything to switch back at 12Z this morning. Now we seem to be doing it all over again. As I stated this morning I really wanted to see the models hold their track constant for 2 good cycles...they were able to hold at 12Z, but the 18Z did not, so we shall see what the 00Z runs have to say.

[biggerbyte]

Indeed a big concern for points more west. If I lived in LA, I'd really be watching right now. Expect more flip flops, but I'm not afraid to say that I see good indications that current thinking for landfall is a bit, maybe a lot, too far east.
We'll see.

[biggerbyte]

Trough, Ridge, and timing. What will be the absolute final outcome?

Stay tuned.

[Scott747]

Another set of runs with the G-IV data.

0z GFS is Pensacola/Panama City with extremely slow movement as it makes landfall before being picked up and taken to the NE. NHC track at 10 was right over Destin.

Chase partner is making preliminary preps for Mobile to Apalachicola...

[Scott747]

Interesting movement after it moves off to the NE for about a day. Moves back to the W/WNW before washing out over the Tennessee Valley.

[unome]

recon http://www.tropicalatlantic.com/recon/a ... n=14&map=1
choose Google Earth Plugin, you can see wind barbs, etc...

Product: Air Force Vortex Message (URNT12 KNHC)
Transmitted: 25th day of the month at 11:01Z
Aircraft: Air Force Aircraft (Last 3 digits of the tail number are 309)
Storm Number & Year: 09L in 2012
Storm Name: Isaac (flight in the North Atlantic basin)
Mission Number: 14
Observation Number: 21
A. Time of Center Fix: 25th day of the month at 10:39:00Z
B. Center Fix Coordinates: 19°32'N 73°36'W (19.5333N 73.6W)
B. Center Fix Location: 107 miles (173 km) to the NW (310°) from Port-au-Prince, Haiti.
C. Minimum Height at Standard Level: 3,055m (10,023ft) at 700mb
D. Estimated (by SFMR or visually) Maximum Surface Wind: 47kts (~ 54.1mph)
E. Location of the Estimated Maximum Surface Wind: 10 nautical miles (12 statute miles) to the N (351°) of center fix
F. Maximum Flight Level Wind Inbound: From 124° at 55kts (From between the ESE and SE at ~ 63.3mph)
G. Location of Maximum Flight Level Wind Inbound: 22 nautical miles (25 statute miles) to the NNE (24°) of center fix
H. Minimum Sea Level Pressure: 1000mb (29.53 inHg)
I. Maximum Flight Level Temp & Pressure Altitude Outside Eye: 6°C (43°F) at a pressure alt. of 3,044m (9,987ft)
J. Maximum Flight Level Temp & Pressure Altitude Inside Eye: 10°C (50°F) at a pressure alt. of 3,051m (10,010ft)
K. Dewpoint Temp (collected at same location as temp inside eye): 8°C (46°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: 700mb
O. Navigation Fix Accuracy: 0.02 nautical miles
O. Meteorological Accuracy: 0 nautical miles
Remarks Section:
Maximum Flight Level Wind: 59kts (~ 67.9mph) in the northeast quadrant at 10:17:30Z


General Notes About Vortex Messages:
- Reported winds are usually averaged over a 10 second period. (NHC advisory wind speeds are the highest expected winds averaged over a 1 minute period.)
- The maximum flight level temperature outside the eye (item I.) "is taken just outside the central region of a cyclone (i.e., just outside the eyewall or just beyond the maximum wind band). This temperature may not be the highest recorded on the inbound leg but is representative of the environmental temperature just outside the central region of the storm."
- The maximum flight level temperature inside the eye (item J.) is the "maximum temperature observed within 5 nm of the center fix coordinates. If a higher temperature is observed at a location more than 5 nm away from the flight level center (item BRAVO), it is reported in Remarks, including bearing and distance from the flight level center."
(Quotes from National Hurricane Operations Plan - NHOP)

[unome]

HPC 72-hr QPF



5-day

[srainhoutx]

BULLETIN
TROPICAL STORM ISAAC INTERMEDIATE ADVISORY NUMBER 17A
NWS NATIONAL HURRICANE CENTER MIAMI FL AL092012
800 AM EDT SAT AUG 25 2012

...CENTER OF ISAAC MOVING INTO THE WINDWARD PASSAGE...


SUMMARY OF 800 AM EDT...1200 UTC...INFORMATION
----------------------------------------------
LOCATION...19.7N 73.8W
ABOUT 95 MI...150 KM ESE OF GUANTANAMO CUBA
ABOUT 105 MI...170 KM SSW OF GREAT INAGUA ISLAND
MAXIMUM SUSTAINED WINDS...60 MPH...95 KM/H
PRESENT MOVEMENT...NW OR 320 DEGREES AT 14 MPH...22 KM/H
MINIMUM CENTRAL PRESSURE...998 MB...29.47 INCHES


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

NONE.

SUMMARY OF WATCHES AND WARNINGS IN EFFECT...

A HURRICANE WARNING IS IN EFFECT FOR...
* THE FLORIDA KEYS INCLUDING THE DRY TORTUGAS
* THE WEST COAST OF FLORIDA FROM BONITA BEACH SOUTHWARD
* FLORIDA BAY

A HURRICANE WATCH IS IN EFFECT FOR...
* HAITI
* THE FLORIDA EAST COAST FROM GOLDEN BEACH SOUTHWARD
* ANDROS ISLAND IN THE BAHAMAS

A TROPICAL STORM WARNING IS IN EFFECT FOR...
* DOMINICAN REPUBLIC
* HAITI
* CUBAN PROVINCES OF CIEGO DE AVILA...SANCTI SPIRITUS...VILLA
CLARA...CAMAGUEY...LAS TUNAS...GRANMA...HOLGUIN...SANTIAGO DE
CUBA...AND GUANTANAMO
* THE BAHAMAS
* TURKS AND CAICOS ISLANDS
* THE FLORIDA EAST COAST FROM JUPITER INLET SOUTHWARD
* LAKE OKEECHOBEE

A TROPICAL STORM WATCH IS IN EFFECT FOR...
* CUBAN PROVINCES OF MATANZAS AND CIENFUEGOS
* JAMAICA
* THE FLORIDA EAST COAST NORTH OF JUPITER INLET TO SEBASTIAN INLET

A HURRICANE WARNING MEANS THAT HURRICANE CONDITIONS ARE EXPECTED
SOMEWHERE WITHIN THE WARNING AREA. A WARNING IS TYPICALLY ISSUED
36 HOURS BEFORE THE ANTICIPATED FIRST OCCURRENCE OF TROPICAL STORM
FORCE WINDS...CONDITIONS THAT MAKE OUTSIDE PREPARATIONS DIFFICULT
OR DANGEROUS. PREPARATIONS TO PROTECT LIFE AND PROPERTY SHOULD BE
RUSHED TO COMPLETION.

A HURRICANE WATCH MEANS THAT HURRICANE CONDITIONS ARE POSSIBLE
WITHIN THE WATCH AREA...IN THIS CASE WITHIN THE NEXT 24 TO 36 HOURS.

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.

INTERESTS IN THE REMAINDER OF CUBA AND THE REMAINDER OF THE FLORIDA
PENINSULA SHOULD MONITOR THE PROGRESS OF ISAAC.

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


DISCUSSION AND 48-HOUR OUTLOOK
------------------------------
AT 800 AM EDT...1200 UTC...THE CENTER OF TROPICAL STORM ISAAC WAS
LOCATED NEAR LATITUDE 19.7 NORTH...LONGITUDE 73.8 WEST. ISAAC IS
MOVING TOWARD THE NORTHWEST NEAR 14 MPH...22 KM/H...AND A
WEST-NORTHWEST TO NORTHWEST MOTION IS EXPECTED TO CONTINUE FOR THE
NEXT COUPLE OF DAYS WITH SOME INCREASE IN FORWARD SPEED. ON THE
FORECAST TRACK...THE CENTER OF ISAAC WILL MOVE NEAR OR OVER EASTERN
CUBA TODAY...AND MOVE NEAR THE NORTH COAST OF CUBA TONIGHT AND
APPROACH THE FLORIDA KEYS ON SUNDAY.

MAXIMUM SUSTAINED WINDS ARE NEAR 60 MPH...95 KM/H...WITH HIGHER
GUSTS. SOME STRENGTHENING IS FORECAST AFTER ISAAC MOVES OVER EASTERN
CUBA LATER TODAY...AND ISAAC IS EXPECTED TO BECOME A HURRICANE ON
SUNDAY.

TROPICAL STORM FORCE WINDS EXTEND OUTWARD UP TO 230 MILES...370 KM
FROM THE CENTER.

THE MINIMUM CENTRAL PRESSURE JUST REPORTED BY AN AIR FORCE RESERVE
HURRICANE HUNTER AIRCRAFT IS 998 MB...29.47 INCHES.


HAZARDS AFFECTING LAND
----------------------
RAINFALL...TOTAL RAINFALL ACCUMULATIONS OF 8 TO 12 INCHES...WITH
MAXIMUM AMOUNTS OF 20 INCHES...ARE POSSIBLE OVER HISPANIOLA. THESE
RAINS COULD CAUSE LIFE-THREATENING FLASH FLOODS AND MUD SLIDES.
TOTAL RAIN ACCUMULATIONS OF 4 TO 8 INCHES...WITH MAXIMUM AMOUNTS OF
12 INCHES...ARE POSSIBLE ACROSS JAMAICA...THE CENTRAL AND EASTERN
PORTIONS OF CUBA...THE FLORIDA KEYS AND THE SOUTHERN PENINSULA OF
FLORIDA. TOTAL RAIN ACCUMULATIONS OF 2 TO 4 INCHES ARE POSSIBLE
OVER THE CENTRAL AND SOUTHEASTERN BAHAMAS.

WIND...TROPICAL STORM CONDITIONS ARE OCCURRING OVER PORTIONS OF THE
DOMINICAN REPUBLIC AND HAITI...EASTERN CUBA...THE SOUTHEASTERN
BAHAMAS AND THE TURKS AND CAICOS ISLANDS. TROPICAL STORM CONDITIONS
ARE EXPECTED OVER THE CENTRAL BAHAMAS LATER TODAY AND TONIGHT...AND
OVER THE NORTHWESTERN BAHAMAS BY SUNDAY MORNING. HURRICANE
CONDITIONS ARE POSSIBLE ON ANDROS ISLAND ON SUNDAY. TROPICAL STORM
CONDITIONS ARE EXPECTED OVER CENTRAL CUBA BY LATER TODAY AND
TONIGHT. TROPICAL STORM CONDITIONS ARE EXPECTED TO REACH
NORTHWESTERN CUBA AND THE NORTHWESTERN BAHAMAS BY TONIGHT OR
SUNDAY.

HURRICANE CONDITIONS ARE EXPECTED IN THE HURRICANE WARNING AREA IN
SOUTHWEST FLORIDA AND THE FLORIDA KEYS ON SUNDAY...WITH TROPICAL
STORM CONDITIONS EXPECTED BY EARLY SUNDAY. HURRICANE CONDITIONS ARE
POSSIBLE IN THE HURRICANE WATCH AREA IN SOUTHEAST FLORIDA ON
SUNDAY...WITH TROPICAL STORM CONDITIONS EXPECTED IN THE TROPICAL
STORM WARNING AREA IN FLORIDA BY EARLY SUNDAY.

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...

SOUTHWEST FLORIDA COAST...5 TO 7 FT
SOUTHEAST FLORIDA COAST AND THE FLORIDA KEYS...1 TO 3 FT
HISPANIOLA AND EASTERN CUBA...1 TO 3 FT
THE BAHAMAS AND TURKS AND CAICOS...1 TO 3 FT

THE DEEPEST WATER WILL OCCUR ALONG THE IMMEDIATE COAST IN AREAS OF
ONSHORE FLOW. 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 DANGEROUS WAVES.

SURF...DANGEROUS SURF AND RIP CURRENT CONDITIONS WILL AFFECT PUERTO
RICO...HISPANIOLA...THE BAHAMAS...THE TURKS AND CAICOS...EASTERN
AND CENTRAL CUBA...AND THE EAST COAST OF FLORIDA AND THE FLORIDA
KEYS DURING THE NEXT COUPLE OF DAYS. PLEASE CONSULT PRODUCTS FROM
YOUR LOCAL WEATHER OFFICE FOR MORE INFORMATION.


NEXT ADVISORY
-------------
NEXT COMPLETE ADVISORY...1100 AM EDT.

$$
FORECASTER BEVEN

[srainhoutx]

PRELIMINARY EXTENDED FORECAST DISCUSSION
NWS HYDROMETEOROLOGICAL PREDICTION CENTER COLLEGE PARK MD
245 AM EDT SAT AUG 25 2012

VALID 12Z WED AUG 29 2012 - 12Z SAT SEP 01 2012


...ISAAC EXPECTED TO MAKE LANDFALL ALONG THE NORTHERN GULF COAST
THIS PERIOD...


USED THE DETERMINISTIC ECMWF FOR THE PRELIMINARY FRONTS AND
PRESSURES FOR DAYS 3 AND 4...SWITCHING TO THE ECENS MEAN
THEREAFTER TO ADDRESS THE UNCERTAINTIES IN SYNOPTIC DETAIL AMONG
THE ARRAY OF GLOBAL MODEL SOLUTIONS. CHOSE TO MANUALLY MODIFY THE
ISOBARS OVER THE DEEP SOUTH NEAR AND AROUND ISAAC TO FIT THE MOST
RECENT NATIONAL HURRICANE CENTER FORECAST...AS OPPOSED TO CHOOSING
A MODEL OF BEST FIT FOR THAT SYSTEM AT THE EXPENSE OF THE FLOW
OVER THE REMAINDER OF THE NATION. IN THIS CASE...THE GFS IS QUITE
CLOSE TO THE OFFICIAL ISAAC FORECAST...BUT DIFFERS ENOUGH FROM THE
OTHER GUIDANCE WITH THE MAIN BAND OF WESTERLIES TO PRECLUDE ITS
WHOLESALE USE

[srainhoutx]

First VIS Imagery suggest that Isaac may well miss the NE tip of Cuba as it heads toward the Florida Straits...