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Hurricane ISAAC


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BULLETIN
HURRICANE ISAAC INTERMEDIATE ADVISORY NUMBER  32A...CORRECTED
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL092012
1200 AM CDT WED AUG 29 2012

CORRECTED SPELLING ERROR IN HEADLINE
 
...ISAAC MOVING SLOWLY ALONG THE COAST OF SOUTHEAST LOUISIANA AND
PRODUCING A DANGEROUS STORM SURGE...FLOODING FROM RAINFALL ALSO
EXPECTED...
 
 
SUMMARY OF 1200 AM CDT...0500 UTC...INFORMATION
-----------------------------------------------
LOCATION...29.0N 90.0W
ABOUT 60 MI...95 KM SE OF HOUMA LOUISIANA
ABOUT 70 MI...110 KM S OF NEW ORLEANS LOUISIANA
MAXIMUM SUSTAINED WINDS...80 MPH...130 KM/H
PRESENT MOVEMENT...WNW OR 290 DEGREES AT 7 MPH...11 KM/H
MINIMUM CENTRAL PRESSURE...969 MB...28.61 INCHES
 
 
WATCHES AND WARNINGS
--------------------
CHANGES WITH THIS ADVISORY...
 
NONE.
 
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 SABINE PASS TEXAS
 
A TROPICAL STORM WATCH IS IN EFFECT FOR...
* EAST OF HIGH ISLAND TEXAS TO JUST WEST OF SABINE PASS
 
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 1200 AM CDT...0500 UTC...
AT 1200 AM CDT...0500 UTC...THE CENTER OF HURRICANE ISAAC WAS
LOCATED NEAR LATITUDE 29.0 NORTH...LONGITUDE 90.0 WEST.  ISAAC HAS
BEEN WOBBLING BUT IS MOVING GENERALLY TOWARD THE WEST-NORTHWEST
NEAR 7 MPH...11 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 WILL CONTINUE MOVING NEAR OR OVER THE
SOUTHEASTERN COAST OF LOUISIANA THIS MORNING...AND MOVE INLAND OVER
SOUTHEASTERN LOUISIANA DURING THE NEXT DAY OR SO.
 
MAXIMUM SUSTAINED WINDS ARE NEAR 80 MPH...130 KM/H...WITH HIGHER
GUSTS.  ISAAC IS A CATEGORY ONE HURRICANE ON THE SAFFIR-SIMPSON
HURRICANE WIND SCALE.  LITTLE CHANGE IN STRENGTH IS FORECAST THIS
MORNING.  SLOW WEAKENING IS EXPECTED AFTER THAT.
 
HURRICANE FORCE WINDS EXTEND OUTWARD UP TO 60 MILES...95 KM...FROM
THE CENTER...AND TROPICAL STORM FORCE WINDS EXTEND OUTWARD UP TO 185
MILES...295 KM.  A SUSTAINED WIND OF 44 MPH WITH A GUST TO 69 MPH
WAS OBSERVED WITHIN THE PAST HOUR AT NEW ORLEANS INTERNATIONAL
AIRPORT.  A SUSTAINED WIND OF 51 MPH WITH A GUST TO 69 MPH WAS
RECENTLY REPORTED AT SHELL BEACH LOUISIANA.
 
THE LATEST MINIMUM CENTRAL PRESSURE REPORTED BY AN AIR FORCE
HURRICANE HUNTER AIRCRAFT WAS 969 MB...28.61 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...3 TO 6 FT
* SOUTH-CENTRAL LOUISIANA...3 TO 6 FT
* FLORIDA PANHANDLE AND 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.
 
A STORM SURGE OF 11.0 FEET WAS RECENTLY REPORTED AT A NATIONAL
OCEAN SERVICE TIDE GAUGE AT SHELL BEACH LOUISIANA.  A STORM SURGE
OF 6.9 FEET WAS OBSERVED AT A NATIONAL OCEAN SERVICE TIDE GAUGE IN
WAVELAND MISSISSIPPI.
 
WIND...TROPICAL STORM CONDITIONS WILL CONTINUE ACROSS THE WARNING
AREA THIS MORNING...AND HURRICANE CONDITIONS WILL CONTINUE TO SPREAD
ONSHORE ACROSS SOUTHEASTERN LOUISIANA.
 
WINDS AFFECTING THE UPPER FLOORS OF HIGH-RISE BUILDINGS WILL BE
SIGNIFICANTLY STRONGER THAN THOSE NEAR GROUND LEVEL. AT ABOUT THE
30TH STORY...WINDS WOULD LIKELY BE ONE SAFFIR-SIMPSON CATEGORY
STRONGER THAN AT THE SURFACE.
 
RAINFALL...ISAAC IS EXPECTED TO PRODUCE TOTAL RAINFALL AMOUNTS OF
7 TO 14 INCHES...WITH POSSIBLE ISOLATED MAXIMUM AMOUNTS OF 20
INCHES...OVER MUCH OF LOUISIANA...SOUTHERN MISSISSIPPI...SOUTHERN
ALABAMA...AND THE EXTREME WESTERN FLORIDA PANHANDLE.  THESE RAINS
COULD RESULT IN SIGNIFICANT LOWLAND FLOODING.
 
TORNADOES...ISOLATED TORNADOES ARE POSSIBLE ALONG THE CENTRAL GULF
COAST REGION AND PARTS OF THE LOWER MISSISSIPPI RIVER VALLEY
THROUGH WEDNESDAY.
 
SURF...DANGEROUS SURF AND RIP CURRENT CONDITIONS WILL CONTINUE TO
AFFECT THE WEST COAST OF FLORIDA AND THE NORTHERN GULF COAST FOR THE
NEXT DAY OR SO.
 
 
NEXT ADVISORY
-------------
NEXT INTERMEDIATE ADVISORY...200 AM CDT.
NEXT COMPLETE ADVISORY...400 AM CDT.
 
$$
FORECASTER PASCH/ROBERTS
 
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