000 WTNT34 KNHC 290656 TCPAT4 BULLETIN HURRICANE ISAAC INTERMEDIATE ADVISORY NUMBER 32B NWS NATIONAL HURRICANE CENTER MIAMI FL AL092012 200 AM CDT WED AUG 29 2012 ...ISAAC REMAINS NEARLY STATIONARY NEAR THE COAST OF SOUTHEAST LOUISIANA...DANGEROUS STORM SURGE AND FLOOD THREAT FROM HEAVY RAINS CONTINUES... SUMMARY OF 200 AM CDT...0700 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...STATIONARY MINIMUM CENTRAL PRESSURE...968 MB...28.58 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...PLEASE MONITOR PRODUCTS ISSUED BY YOUR LOCAL NATIONAL WEATHER SERVICE FORECAST OFFICE. DISCUSSION AND 48-HOUR OUTLOOK ------------------------------ AT 200 AM CDT...0700 UTC...THE CENTER OF HURRICANE ISAAC WAS LOCATED NEAR LATITUDE 29.0 NORTH...LONGITUDE 90.0 WEST. ISAAC HAS MOVED LITTLE OVER THE PAST FEW HOURS...BUT A SLOW NORTHWESTWARD MOTION IS EXPECTED TO RESUME LATER THIS MORNING. 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 175 MILES...280 KM. A SUSTAINED WIND OF 56 MPH WITH A GUST TO 71 MPH WAS OBSERVED WITHIN THE PAST HOUR AT LAKEFRONT AIRPORT IN NEW ORLEANS. A SUSTAINED WIND OF 45 MPH WITH A GUST TO 67 MPH WAS RECENTLY REPORTED AT BOOTHVILLE LOUISIANA. THE LATEST MINIMUM CENTRAL PRESSURE REPORTED BY AN AIR FORCE HURRICANE HUNTER AIRCRAFT WAS 968 MB...28.58 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 10.7 FEET WAS RECENTLY REPORTED AT SHELL BEACH LOUISIANA. A STORM SURGE OF 7.5 FEET WAS RECENTLY REPORTED 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 COMPLETE ADVISORY...400 AM CDT. $$ FORECASTER PASCH/ROBERTS