000 WTNT34 KNHC 292358 TCPAT4 BULLETIN TROPICAL STORM ISAAC INTERMEDIATE ADVISORY NUMBER 35A NWS NATIONAL HURRICANE CENTER MIAMI FL AL092012 700 PM CDT WED AUG 29 2012 ...SLOW-MOVING ISAAC DUMPING HEAVY RAINS AND STILL PRODUCING A SIGNIFICANT STORM SURGE... SUMMARY OF 700 PM CDT...0000 UTC...INFORMATION ---------------------------------------------- LOCATION...30.1N 91.1W ABOUT 30 MI...50 KM S OF BATON ROUGE LOUISIANA ABOUT 60 MI...95 KM W OF NEW ORLEANS LOUISIANA MAXIMUM SUSTAINED WINDS...60 MPH...90 KM/H PRESENT MOVEMENT...NW OR 315 DEGREES AT 5 MPH...7 KM/H MINIMUM CENTRAL PRESSURE...977 MB...28.85 INCHES WATCHES AND WARNINGS -------------------- CHANGES WITH THIS ADVISORY... THE TROPICAL STORM WARNING EAST OF THE MISSISSIPPI-ALABAMA BORDER HAS BEEN DISCONTINUED. SUMMARY OF WATCHES AND WARNINGS IN EFFECT... A TROPICAL STORM WARNING IS IN EFFECT FOR... * CAMERON LOUISIANA TO THE MISSISSIPPI-ALABAMA BORDER FOR STORM INFORMATION SPECIFIC TO YOUR AREA...INCLUDING POSSIBLE INLAND WATCHES AND WARNINGS...PLEASE MONITOR PRODUCTS ISSUED BY YOUR LOCAL NATIONAL WEATHER SERVICE FORECAST OFFICE. DISCUSSION AND 48-HOUR OUTLOOK ------------------------------ AT 700 PM CDT...0000 UTC...THE CENTER OF TROPICAL STORM ISAAC WAS LOCATED BY NOAA DOPPLER WEATHER RADAR NEAR LATITUDE 30.1 NORTH... LONGITUDE 91.1 WEST. ISAAC IS MOVING TOWARD THE NORTHWEST NEAR 5 MPH...7 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 TONIGHT AND TOMORROW...AND MOVE OVER SOUTHERN ARKANSAS BY EARLY FRIDAY. MAXIMUM SUSTAINED WINDS HAVE DECREASED TO NEAR 60 MPH...90 KM/H... WITH HIGHER GUSTS. THE STRONGEST WINDS ARE PRIMARILY OCCURRING OVER WATER OR NEAR THE COAST. STEADY WEAKENING IS EXPECTED DURING THE NEXT 48 HOURS AS ISAAC CONTINUES TO MOVE FARTHER INLAND...AND ISAAC IS FORECAST TO BECOME A TROPICAL DEPRESSION BY THURSDAY NIGHT. TROPICAL-STORM-FORCE WINDS EXTEND OUTWARD UP TO 175 MILES...280 KM FROM THE CENTER. SUSTAINED WINDS OF 46 MPH WITH A GUST TO 55 MPH WAS RECENTLY REPORTED NEAR MANDEVILLE LOUISIANA. A WIND GUST TO 67 MPH WAS REPORTED AT GULFPORT MISSISSIPPI DURING THE PAST COUPLE OF HOURS. THE ESTIMATED MINIMUM CENTRAL PRESSURE BASED ON NEARBY SURFACE OBSERVATIONS IS 977 MB...28.85 INCHES. HAZARDS AFFECTING LAND ---------------------- EVEN THOUGH ISAAC IS NO LONGER A HURRICANE...LIFE-THREATENING HAZARDS FROM STORM SURGE AND INLAND FLOODING ARE STILL OCCURRING. 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 * SOUTH-CENTRAL LOUISIANA...3 TO 6 FT * ALABAMA...2 TO 4 FT * FLORIDA PANHANDLE AND APALACHEE BAY...1 TO 2 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 NEARLY 7 FEET IS STILL OCCURRING AT WAVELAND MISSISSIPPI. WIND...TROPICAL STORM CONDITIONS WILL CONTINUE ACROSS THE WARNING AREA THROUGH TONIGHT. RAINFALL...ISAAC IS EXPECTED TO PRODUCE TOTAL RAINFALL AMOUNTS OF 7 TO 14 INCHES...WITH POSSIBLE ISOLATED MAXIMUM AMOUNTS OF 25 INCHES...OVER MUCH OF LOUISIANA...SOUTHERN AND CENTRAL MISSISSIPPI...SOUTHWEST ALABAMA AND SOUTHERN AND CENTRAL ARKANSAS THROUGH FRIDAY. THESE RAINS COULD RESULT IN SIGNIFICANT LOWLAND FLOODING. AN UNOFFICIAL RAINFALL TOTAL OF 18.35 INCHES HAS BEEN REPORTED IN GRETNA LOUISIANA...LOCATED IN METROPOLITAN NEW ORLEANS. 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 COMPLETE ADVISORY...1000 PM CDT. $$ FORECASTER BROWN/KIMBERLAIN