000 WTNT41 KNHC 062050 TCDAT1 TROPICAL STORM ANDREA DISCUSSION NUMBER 5 NWS NATIONAL HURRICANE CENTER MIAMI FL AL012013 500 PM EDT THU JUN 06 2013 THE CENTER OF ANDREA IS NOW NEAR THE COAST OF THE FLORIDA BIG BEND REGION. ALTHOUGH THE CENTRAL CONVECTION HAS WEAKENED CONSIDERABLY SINCE THIS MORNING...AN AIR FORCE RESERVE HURRICANE HUNTER AIRCRAFT FOUND AN INNER WIND CORE...WITH SFMR SURFACE WIND ESTIMATES OF 55 KT ABOUT 20 N MI EAST OF THE CENTER AND 850 MB FLIGHT-LEVEL WINDS OF 71 KT. THE MINIMUM CENTRAL PRESSURE WAS 993 MB. ALTHOUGH IT IS POSSIBLE THAT THERE WAS A SHOALING CONTRIBUTION TO THE SFMR DATA...THE INITIAL INTENSITY IS ESTIMATED AT 55 KT. NO ADDITIONAL STRENGTHENING IS EXPECTED BEFORE LANDFALL. THE INITIAL MOTION IS 040/15. ANDREA SHOULD ACCELERATE INTO THE WESTERLIES DURING THE NEXT 24-48 HOURS AND MOVE QUICKLY NORTHEASTWARD ALONG THE U. S. EAST COAST AND NEAR THE CANADIAN MARITIMES. AFTER 48 HOURS...THE CYCLONE IS EXPECTED TO TURN EASTWARD AND MOVE RAPIDLY INTO THE OPEN ATLANTIC...WITH THIS GENERAL MOTION CONTINUING UNTIL DISSIPATION. WHILE THE GUIDANCE SHOWS SOME SPREAD IN BOTH DIRECTION AND SPEED...THERE IS NO SIGNIFICANT CHANGE SINCE THE LAST ADVISORY AND THE NEW FORECAST TRACK IS SIMILAR TO THE OLD ONE. ANDREA SHOULD WEAKEN AFTER LANDFALL. SUBSEQUENTLY...THE CYCLONE SHOULD GRADUALLY MERGE WITH A BAROCLINIC ZONE AS IT MOVES OVER AND NEAR THE EASTERN UNITED STATES...WHICH SHOULD RESULT IN EXTRATROPICAL TRANSITION OCCURRING DURING THE NEXT 36 HOURS. AFTER THAT...THE CYCLONE SHOULD CONTINUE AS AN EXTRATROPICAL GALE UNTIL DISSIPATION AROUND 120 HOURS. THERE IS A CHANCE THAT THE CONVECTION COULD DISSIPATE BEFORE EXTRATROPICAL TRANSITION IS COMPLETE...WHICH COULD CAUSE ANDREA TO HAVE A POST-TROPICAL PHASE BEFORE IT BECOMES EXTRATROPICAL. THERE ARE NO CHANGES TO THE TROPICAL STORM WARNINGS ON THIS ADVISORY. BASED ON THE ASSUMPTION THAT ANDREA WILL BECOME POST-TROPICAL/EXTRATOPICAL IN ABOUT 36 HOURS...WE DO NOT EXPECT TO EXTEND THE TROPICAL WARNINGS ANY FARTHER NORTH ALONG THE COAST. OUR CURRENT INTENTION IS THAT ANY HAZARDOUS WIND CONDITIONS FROM THE DELMARVA PENINSULA NORTHWARD TO NEW ENGLAND WOULD BE HANDLED BY LOCAL NATIONAL WEATHER SERVICE WARNING PRODUCTS. REGARDLESS OF THE EXACT TRACK OF THE CENTER OF ANDREA...THE PRIMARY EFFECTS ARE EXPECTED TO BE HEAVY RAINFALL ACROSS MUCH OF THE FLORIDA PENINSULA AND INTO THE COASTAL SECTIONS OF THE SOUTHEASTERN UNITED STATES...STORM SURGE FLOODING ALONG PORTIONS OF THE WEST COAST OF FLORIDA...AND ISOLATED TORNADOES TONIGHT FROM THE FLORIDA PENINSULA NORTHWARD THROUGH THE COASTAL PORTIONS OF GEORGIA...SOUTH CAROLINA...AND NORTH CAROLINA. FORECAST POSITIONS AND MAX WINDS INIT 06/2100Z 29.5N 83.4W 55 KT 65 MPH...NEAR COAST 12H 07/0600Z 31.9N 81.4W 45 KT 50 MPH...INLAND 24H 07/1800Z 35.6N 78.2W 40 KT 45 MPH...INLAND 36H 08/0600Z 39.8N 73.3W 40 KT 45 MPH...POST-TROP/EXTRATROP 48H 08/1800Z 43.8N 67.2W 40 KT 45 MPH...POST-TROP/EXTRATROP 72H 09/1800Z 46.6N 50.0W 35 KT 40 MPH...POST-TROP/EXTRATROP 96H 10/1800Z 46.0N 29.5W 35 KT 40 MPH...POST-TROP/EXTRATROP 120H 11/1800Z...DISSIPATED $$ FORECASTER BEVEN