000 WTNT41 KNHC 060242 TCDAT1 TROPICAL STORM ANDREA DISCUSSION NUMBER 2 NWS NATIONAL HURRICANE CENTER MIAMI FL AL012013 1000 PM CDT WED JUN 05 2013 SATELLITE IMAGERY INDICATES THAT THE STRUCTURE OF ANDREA HAS NOT CHANGED MUCH OVER THE PAST FEW HOURS. MOST OF THE DEEP CONVECTION REMAINS DISPLACED IN BANDS AND CLUSTERS WELL TO THE EAST AND SOUTHEAST OF THE CENTER DUE TO APPROXIMATELY 25 KT OF SOUTHWESTERLY SHEAR. THE INITIAL INTENSITY REMAINS 35 KT AND THE CENTRAL PRESSURE OF 1002 MB IS SUPPORED BY A RECENT OBSERVATION OF 1003 MB WITH 20 KT OF WIND FROM NOAA BUOY 42003. ANOTHER AIR FORCE RESERVE HURRICANE HUNTER AIRCRAFT WILL BE SAMPLING ANDREA OVERNIGHT AND PROVIDE INFORMATION ON THE INTENSITY AND STRUCTURE OF THE CYCLONE. WHILE ANDREA WILL REMAIN IN A MARGINAL ENVIRONMENT FOR STRENGTHENING AS A TROPICAL CYCLONE...BAROCLINIC FORCING AHEAD OF AN UPPER- TROUGH WILL BEGIN TO AFFECT THE SYSTEM IN THE NEXT 24 HOURS. THIS FORCING SHOULD RESULT IN SOME DEEPENING FROM A PRESSURE STANDPOINT...BUT LITTLE CHANGE IN THE PEAK WINDS IS EXPECTED BEFORE OR AFTER ANDREA BECOMES EXTRATROPICAL IN ABOUT 48 HOURS. THE INITIAL MOTION ESTIMATE IS AN UNCERTAIN 010/05...GIVEN THE RELATIVELY RECENT REFORMATION OF THE CURRENT CENTER EARLIER TODAY. A GRADUAL ACCELERATION TOWARD THE NORTH-NORTHEAST AND NORTHEAST IS EXPECTED DURING THE NEXT COUPLE OF DAYS AHEAD OF A MID- TO UPPER-LEVEL TROUGH THAT IS MOVING INTO THE EASTERN UNITED STATES. WHILE OVERALL THE GLOBAL MODELS ARE IN GENERAL AGREEMENT ON THIS SCENARIO...THERE REMAIN SOME SIZEABLE DIFFERENCES IN FORWARD SPEED. IN PARTICULAR...THE GFS REMAINS QUITE FAST AND SHOWS A SOMEWHAT DISCONTINUOUS TRACK OF THE LOW COMPARED TO THE ECMWF AND THE ECMWF AND GEFS ENSEMBLE MEANS. THE NEW NHC FORECAST IS CLOSE TO THE PREVIOUS ONE AND IS RELATIVELY CLOSE TO THE ECMWF THROUGH THE PERIOD. 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...STORM SURGE FLOODING ALONG PORTIONS OF THE WEST COAST OF FLORIDA...AND ISOLATED TORNADOES OVERNIGHT AND THURSDAY ACROSS THE FLORIDA PENINSULA. FORECAST POSITIONS AND MAX WINDS INIT 06/0300Z 26.0N 86.3W 35 KT 40 MPH 12H 06/1200Z 27.3N 85.6W 40 KT 45 MPH 24H 07/0000Z 29.6N 83.7W 40 KT 45 MPH 36H 07/1200Z 33.0N 80.3W 40 KT 45 MPH...INLAND 48H 08/0000Z 37.5N 75.8W 40 KT 45 MPH...POST-TROP/EXTRATROP 72H 09/0000Z 44.0N 61.0W 40 KT 45 MPH...POST-TROP/EXTRATROP 96H 10/0000Z 44.5N 42.0W 40 KT 45 MPH...POST-TROP/EXTRATROP 120H 11/0000Z 47.5N 20.0W 40 KT 45 MPH...POST-TROP/EXTRATROP $$ FORECASTER BRENNAN