000 WTNT34 KNHC 221447 TCPAT4 BULLETIN TROPICAL STORM ISAAC ADVISORY NUMBER 6 NWS NATIONAL HURRICANE CENTER MIAMI FL AL092012 1100 AM AST WED AUG 22 2012 ...RAINBANDS OF ISAAC SPREADING THROGH THE LESSER ANTILLES... SUMMARY OF 1100 AM AST...1500 UTC...INFORMATION ----------------------------------------------- LOCATION...15.9N 59.3W ABOUT 140 MI...230 KM E OF GUADELOUPE MAXIMUM SUSTAINED WINDS...45 MPH...75 KM/H PRESENT MOVEMENT...W OR 280 DEGREES AT 21 MPH...33 KM/H MINIMUM CENTRAL PRESSURE...1006 MB...29.71 INCHES WATCHES AND WARNINGS -------------------- CHANGES WITH THIS ADVISORY... NONE. SUMMARY OF WATCHES AND WARNINGS IN EFFECT... A TROPICAL STORM WARNING IS IN EFFECT FOR... * MARTINIQUE * DOMINICA * GUADELOUPE AND THE SURROUNDING ISLANDS...AND ST. MARTIN * ST. KITTS...NEVIS...ANTIGUA...BARBUDA...MONTSERRAT...AND ANGUILLA * SABA...ST. EUSTATIUS...AND ST. MAARTEN * BRITISH VIRGIN ISLANDS * PUERTO RICO...VIEQUES...CULEBRA...AND THE U.S. VIRGIN ISLANDS A HURRICANE WATCH IS IN EFFECT FOR... * PUERTO RICO...VIEQUES...CULEBRA...AND THE U.S. AND BRITISH VIRGIN ISLANDS * SOUTH COAST OF DOMINICAN REPUBLIC FROM ISLA SAONA WESTWARD TO THE HAITI-DOMINICAN REPUBLIC SOUTHERN BORDER A TROPICAL STORM WATCH IS IN EFFECT FOR... * NORTH COAST OF DOMINICAN REPUBLIC FROM THE HAITI-DOMINICAN REPUBLIC NORTHERN BORDER EASTWARD TO NORTH OF ISLA SAONA 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. INTERESTS IN HAITI AND CUBA SHOULD MONITOR THE PROGRESS OF ISAAC. 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 1100 AM AST...1500 UTC...THE CENTER OF TROPICAL STORM ISAAC WAS LOCATED NEAR LATITUDE 15.9 NORTH...LONGITUDE 59.3 WEST. ISAAC IS MOVING TOWARD THE WEST NEAR 21 MPH...33 KM/H...AND THIS GENERAL MOTION IS EXPECTED TO CONTINUE FOR THE NEXT COUPLE OF DAYS. ON THE FORECAST TRACK...THE CENTER OF ISAAC SHOULD MOVE THROUGH THE LEEWARD ISLANDS THIS EVENING...PASS NEAR OR SOUTH OF THE VIRGIN ISLANDS AND PUERTO RICO ON THURSDAY...AND APPROACH THE DOMINICAN REPUBLIC THURSDAY NIGHT AND FRIDAY. MAXIMUM SUSTAINED WINDS ARE NEAR 45 MPH...75 KM/H...WITH HIGHER GUSTS. STRENGTHENING IS FORECAST DURING THE NEXT 48 HOURS...AND ISAAC COULD BECOME A HURRICANE BY THURSDAY OR THURSDAY NIGHT. TROPICAL STORM FORCE WINDS EXTEND OUTWARD UP TO 60 MILES...95 KM FROM THE CENTER. ESTIMATED MINIMUM CENTRAL PRESSURE IS 1006 MB...29.71 INCHES. HAZARDS AFFECTING LAND ---------------------- WIND...TROPICAL STORM CONDITIONS ARE EXPECTED TO REACH THE LEEWARD ISLANDS BY THIS AFTERNOON OR EVENING...MAKING OUTSIDE PREPARATIONS DIFFICULT OR DANGEROUS. TROPICAL STORM CONDITIONS ARE EXPECTED OVER PUERTO RICO AND THE U.S. AND BRITISH VIRGIN ISLANDS ON THURSDAY. HURRICANE CONDITIONS ARE POSSIBLE OVER PUERTO RICO...THE U.S. VIRGIN ISLANDS ON THURSDAY...AND OVR THE DOMINICAN REPUBLIC BY LATE THURSDAY. RAINFALL...TOTAL RAIN ACCUMULATIONS OF 4 TO 8 INCHES ARE POSSIBLE OVER THE NORTHERN WINDWARD ISLANDS AND THE LEEWARD ISLANDS. TOTAL RAIN ACCUMULATIONS OF 1 TO 3 INCHES WITH MAXIMUM AMOUNTS OF 6 INCHES ARE POSSIBLE OVER PUERTO RICO AND THE VIRGIN ISLANDS. TOTAL RAINFALL ACCUMULATIONS OF 8 TO 12 INCHES...WITH MAXIMUM AMOUNTS OF 20 INCHES...ARE POSSIBLE OVER HISPANIOLA. THESE RAINS COULD CAUSE LIFE-THREATENING FLASH FLOODS AND MUD SLIDES. STORM SURGE...A STORM SURGE WILL RAISE WATER LEVELS BY AS MUCH AS 1 TO 3 FEET ABOVE NORMAL TIDE LEVELS IN THE NORTHERN LEEWARD ISLANDS...PUERTO RICO...AND THE U.S. AND BRITISH VIRGIN ISLANDS. NEAR THE COAST...THE SURGE WILL BE ACCOMPANIED BY DANGEROUS WAVES. SURF...DANGEROUS SURF AND RIP CURRENT CONDITIONS WILL AFFECT THE WINDWARD AND LEEWARD ISLANDS DURING THE NEXT COUPLE OF DAYS. PLEASE CONSULT PRODUCTS FROM YOUR LOCAL WEATHER OFFICE FOR MORE INFORMATION. NEXT ADVISORY ------------- NEXT INTERMEDIATE ADVISORY...200 PM AST. NEXT COMPLETE ADVISORY...500 PM AST. $$ FORECASTER BEVEN