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Hurricane ISAAC


ZCZC MIATCPAT4 ALL
TTAA00 KNHC DDHHMM
 
BULLETIN
HURRICANE ISAAC INTERMEDIATE ADVISORY NUMBER  34A
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL092012
1200 PM CDT WED AUG 29 2012
 
...ISAAC SOAKING SOUTHEASTERN LOUISIANA AND SOUTHERN MISSISSIPPI
WITH HEAVY RAIN...DANGEROUS COASTAL STORM SURGE AND INLAND FLOOD
THREAT EXPECTED THROUGH TONIGHT...
 
 
SUMMARY OF 1200 PM CDT...1700 UTC...INFORMATION
-----------------------------------------------
LOCATION...29.7N 90.8W
ABOUT 10 MI...15 KM NW OF HOUMA LOUISIANA
ABOUT 45 MI...75 KM WSW OF NEW ORLEANS LOUISIANA
MAXIMUM SUSTAINED WINDS...75 MPH...120 KM/H
PRESENT MOVEMENT...NW OR 310 DEGREES AT 6 MPH...9 KM/H
MINIMUM CENTRAL PRESSURE...973 MB...28.73 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...
* EAST OF THE MISSISSIPPI-ALABAMA BORDER TO THE ALABAMA-FLORIDA
BORDER
* 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...PLEASE MONITOR
PRODUCTS ISSUED BY YOUR LOCAL NATIONAL WEATHER SERVICE FORECAST
OFFICE. 
 
 
DISCUSSION AND 48-HOUR OUTLOOK
------------------------------
AT 1200 PM CDT...1700 UTC...THE CENTER OF HURRICANE ISAAC WAS
LOCATED BY NOAA DOPPLER WEATHER RADAR NEAR LATITUDE 29.7 NORTH...
LONGITUDE 90.8 WEST. ISAAC IS MOVING TOWARD THE NORTHWEST NEAR 6
MPH...9 KM/H. THIS GENERAL MOTION IS EXPECTED TO CONTINUE THROUGH
TONIGHT...FOLLOWED BY A TURN TOWARD THE NORTH-NORTHWEST BY THURSDAY
NIGHT OR EARLY FRIDAY. ON THE FORECAST TRACK...THE CENTER OF ISAAC
WILL MOVE FARTHER INLAND OVER LOUISIANA TODAY AND TOMORROW...AND
MOVE OVER SOUTHERN ARKANSAS BY EARLY FRIDAY.
 
MAXIMUM SUSTAINED WINDS ARE NEAR 75 MPH...120 KM/H...WITH HIGHER
GUSTS. ISAAC IS A CATEGORY ONE HURRICANE ON THE SAFFIR-SIMPSON
HURRICANE WIND SCALE. GRADUAL WEAKENING IS FORECAST DURING THE NEXT
48 HOURS AS ISAAC CONTINUES MOVING FARTHER INLAND...AND ISAAC IS
EXPECTED TO WEAKEN TO A TROPICAL STORM LATER TODAY.
 
HURRICANE-FORCE WINDS EXTEND OUTWARD UP TO 45 MILES...75 KM...FROM
THE CENTER...AND TROPICAL-STORM-FORCE WINDS EXTEND OUTWARD UP TO 175
MILES...280 KM.
 
A GUST TO 71 MPH WAS RECENTLY REPORTED AT PILOT STATION NEAR THE
MOUTH OF THE MISSISSIPPI RIVER.
 
THE ESTIMATED MINIMUM CENTRAL PRESSURE BASED ON NEARBY SURFACE
OBSERVATIONS IS 973 MB...28.73 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
 
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.
 
STORM SURGE VALUES OF ABOUT 8 FEET HAVE RECENTLY BEEN REPORTED AT
SHELL BEACH LOUISIANA AND WAVELAND MISSISSIPPI.
 
WIND...TROPICAL STORM CONDITIONS WILL CONTINUE ACROSS THE WARNING
AREA TODAY...AND HURRICANE CONDITIONS WILL CONTINUE TO AFFECT
PORTIONS OF SOUTHEASTERN LOUISIANA AND MISSISSIPPI IN THE HURRICANE
WARNING AREA INTO THIS AFTERNOON.
 
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...AND
SOUTHWEST ALABAMA THROUGH FRIDAY MORNING. THESE RAINS COULD RESULT
IN SIGNIFICANT LOWLAND FLOODING. RAINS ARE EXPECTED TO INCREASE
NORTHWARD INTO ARKANSAS ON THURSDAY...WITH AMOUNTS OF 3 TO 6 INCHES
EXPECTED OVER SOUTHERN ARKANSAS BY FRIDAY MORNING.
 
TORNADOES...ISOLATED TORNADOES ARE POSSIBLE ALONG THE CENTRAL GULF
COAST REGION AND PARTS OF THE LOWER MISSISSIPPI RIVER VALLEY
THROUGH THURSDAY.
 
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 PM CDT.
NEXT COMPLETE ADVISORY...400 PM CDT.
 
$$
FORECASTER STEWART/ZELINSKY
 
NNNN


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Page last modified: Monday, 31-Dec-2012 12:09:25 UTC