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Tropical Storm ISAAC


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BULLETIN
TROPICAL STORM ISAAC ADVISORY NUMBER  25
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL092012
500 AM EDT MON AUG 27 2012
 
...ISAAC CONTINUES WEST-NORTHWESTWARD...EXPECTED TO STRENGTHEN...NEW
WATCHES AND WARNINGS ISSUED FOR THE COAST OF LOUISIANA...
 
 
SUMMARY OF 500 AM EDT...0900 UTC...INFORMATION
----------------------------------------------
LOCATION...25.2N 84.2W
ABOUT 180 MI...290 KM SW OF FT. MYERS FLORIDA
ABOUT 405 MI...650 KM SE OF THE MOUTH OF THE MISSISSIPPI RIVER
MAXIMUM SUSTAINED WINDS...65 MPH...100 KM/H
PRESENT MOVEMENT...WNW OR 300 DEGREES AT 14 MPH...22 KM/H
MINIMUM CENTRAL PRESSURE...990 MB...29.23 INCHES
 
 
WATCHES AND WARNINGS
--------------------
CHANGES WITH THIS ADVISORY...
 
A TROPICAL STORM WARNING HAS BEEN ISSUED FROM INTRACOASTAL CITY TO
MORGAN CITY LOUISIANA.
 
A HURRICANE WATCH HAS BEEN ISSUED FROM INTRACOASTAL CITY TO MORGAN
CITY LOUISIANA.
 
A TROPICAL STORM WATCH HAS BEEN ISSUED FROM EAST OF SABINE PASS TO
WEST OF INTRACOASTAL CITY LOUISIANA.
 
THE HURRICANE WATCH FOR THE FLORIDA PANHANDLE FROM EAST OF DESTIN
TO INDIAN PASS HAS BEEN DISCONTINUED.
 
THE TROPICAL STORM WARNING HAS BEEN DISCONTINUED ALONG THE EAST
COAST OF FLORIDA NORTH OF OCEAN REEF AND FOR LAKE OKEECHOBEE.
 
SUMMARY OF WATCHES AND WARNINGS IN EFFECT...
 
A HURRICANE WARNING IS IN EFFECT FOR...
* EAST OF MORGAN CITY LOUISIANA TO DESTIN FLORIDA...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 FLORIDA PENINSULA FROM OCEAN REEF SOUTHWARD ON THE EAST COAST
AND FROM TARPON SPRINGS SOUTHWARD ON THE WEST COAST
* FLORIDA KEYS...INCLUDING THE DRY TORTUGAS AND FLORIDA BAY
* EAST OF DESTIN FLORIDA TO THE SUWANNEE 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. 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. A WATCH IS TYPICALLY ISSUED 48 HOURS
BEFORE THE ANTICIPATED FIRST OCCURRENCE OF TROPICAL STORM FORCE
WINDS...CONDITIONS THAT MAKE OUTSIDE PREPARATIONS DIFFICULT OR
DANGEROUS.
 
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.
 
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. 
 
 
DISCUSSION AND 48-HOUR OUTLOOK
------------------------------
AT 500 AM EDT...0900 UTC...THE CENTER OF TROPICAL STORM ISAAC WAS
LOCATED BY AN AIR FORCE RESERVE HURRICANE HUNTER AIRCRAFT NEAR
LATITUDE 25.2 NORTH...LONGITUDE 84.2 WEST. ISAAC IS MOVING TOWARD
THE WEST-NORTHWEST NEAR 14 MPH...22 KM/H...AND THIS GENERAL MOTION
IS EXPECTED TO CONTINUE TODAY WITH A GRADUAL DECREASE IN FORWARD
SPEED. A TURN TOWARD THE NORTHWEST IS EXPECTED ON TUESDAY. ON THE
FORECAST TRACK...THE CENTER OF ISAAC WILL MOVE OVER THE EASTERN
GULF OF MEXICO TODAY AND APPROACH THE NORTHERN GULF COAST IN THE
HURRICANE WARNING AREA ON TUESDAY.
 
MAXIMUM SUSTAINED WINDS ARE NEAR 65 MPH...100 KM/H...WITH HIGHER
GUSTS. SOME STRENGTHENING IS FORECAST DURING THE NEXT 48 HOURS...AND
ISAAC IS EXPECTED TO BECOME A HURRICANE IN A DAY OR SO.
 
TROPICAL STORM FORCE WINDS EXTEND OUTWARD UP TO 240 MILES...390
KM...FROM THE CENTER.
 
THE ESTIMATED MINIMUM CENTRAL PRESSURE BASED ON DATA FROM THE
AIRCRAFT IS 990 MB...29.23 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...
 
* SOUTHEAST LOUISIANA...MISSISSIPPI...AND ALABAMA...6 TO 12 FT
* SOUTH-CENTRAL LOUISIANA...3 TO 6 FT
* FLORIDA PANHANDLE...3 TO 6 FT
* FLORIDA WEST COAST INCLUDING APALACHEE BAY...1 TO 3 FT
* SOUTHEAST FLORIDA COAST AND THE FLORIDA KEYS...1 TO 2 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 LARGE AND DANGEROUS WAVES.
 
WIND...TROPICAL STORM CONDITIONS ARE OCCURRING OVER THE FLORIDA
KEYS...AND SHOULD SPREAD NORTHWARD ALONG THE FLORIDA WEST COAST IN
THE TROPICAL STORM WARNING AREA TODAY.
 
TROPICAL STORM CONDITIONS ARE EXPECTED TO REACH THE NORTHERN GULF
COAST IN THE HURRICANE WARNING AREA LATER TODAY...WITH HURRICANE
CONDITIONS EXPECTED ON TUESDAY.
 
RAINFALL...ISAAC IS EXPECTED TO PRODUCE ADDITIONAL RAIN
ACCUMULATIONS OF 1 TO 3 INCHES OVER CENTRAL AND SOUTHERN FLORIDA...
WHERE ISOLATED MAXIMUM STORM TOTAL AMOUNTS OF 15 INCHES ARE
POSSIBLE. TOTAL RAINFALL AMOUNTS OF 6 TO 12 INCHES...WITH MAXIMUM
AMOUNTS OF 18 INCHES...ARE POSSIBLE IN SOUTHEASTERN LOUISIANA...
SOUTHERN ALABAMA...MISSISSIPPI AND THE WESTERN FLORIDA PANHANDLE.
 
TORNADOES...ISOLATED TORNADOES ARE POSSIBLE FROM CENTRAL FLORIDA
THROUGH THE NORTHEASTERN GULF COAST TODAY AND TONIGHT. THE TORNADO
THREAT WILL DIMINISH OVER SOUTH FLORIDA AND THE FLORIDA KEYS THIS
MORNING.
 
SURF...DANGEROUS SURF AND RIP CURRENT CONDITIONS WILL CONTINUE TO
AFFECT THE NORTHWESTERN BAHAMAS...THE FLORIDA PENINSULA AND THE
FLORIDA KEYS DURING THE NEXT DAY OR SO...AND BEGIN TO AFFECT
PORTIONS OF THE NORTHERN GULF COAST TODAY. PLEASE CONSULT PRODUCTS
FROM YOUR LOCAL WEATHER OFFICE FOR MORE INFORMATION.
 
 
NEXT ADVISORY
-------------
NEXT INTERMEDIATE ADVISORY...800 AM EDT.
NEXT COMPLETE ADVISORY...1100 AM EDT.
 
$$
FORECASTER BRENNAN
 
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