000 WTNT41 KNHC 230300 TCDAT1 TROPICAL STORM FAY DISCUSSION NUMBER 30 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL062008 1100 PM EDT FRI AUG 22 2008 THE CENTER OF FAY CROSSED THE COAST OF THE BIG BEND AREA OF FLORIDA NEAR KEATON BEACH AT ABOUT 2200 UTC...EMERGING OVER APALACHEE BAY IN THE EXTREME NORTHEASTERN GULF OF MEXICO. THE CIRCULATION CENTER ITSELF IS NOT ESPECIALLY WELL-DEFINED IN RADAR IMAGERY...BUT A POTENT NARROW BAND OF CONVECTION HAS PERSISTED OVER WATER IN THE SOUTHERN SEMICIRCLE. FLIGHT-LEVEL AND SFMR DATA FROM AN AIR FORCE RECONNAISSANCE AIRCRAFT SUGGEST THE MAXIMUM WINDS IN THIS BAND ARE ABOUT 45 KT...SO THAT IS THE INITIAL INTENSITY. AN EXPANSIVE RAIN SHIELD EXTENDS WELL INLAND TO THE NORTH OF THE CENTER...AND WHILE WINDS ARE GUSTY IN THOSE REGIONS...SUSTAINED WINDS OF TROPICAL STORM FORCE DO NOT APPEAR TO BE OCCURRING INLAND. THE AIRCRAFT FIXES LEAD TO AN INITIAL MOTION ESTIMATE OF 270/7...AS FAY LUMBERS ALONG TO THE WEST ALONG THE SOUTHERN PERIPHERY OF A MID-LEVEL RIDGE OVER THE NORTHEASTERN UNITED STATES. THAT RIDGE SHOULD CONTINUE TO FORCE FAY WESTWARD FOR THE NEXT COUPLE OF DAYS AT SPEED SIMILAR TO THAT CURRENTLY OBSERVED. AS A RESULT...FAY WILL BE SKIRTING THE FLORIDA PANHANDLE...ALABAMA...AND MISSISSIPPI COASTS DURING THE NEXT COUPLE OF DAYS. THE VARIOUS TRACK MODELS ARE IN QUITE GOOD AGREEMENT ON THIS SCENARIO THROUGH ABOUT 48 HOURS. THEREAFTER...MODEL GUIDANCE FORECASTS THE STEERING CURRENTS TO COLLAPSE AGAIN...AND VARIOUS SOLUTIONS ENSUE REGARDING WHERE AND HOW FAST A WEAKENING FAY WILL GO. MOST OF THE MODELS SHOW RELATIVELY LITTLE NET MOTION ON DAYS 3 THROUGH 5. THE NEW OFFICIAL TRACK FORECAST ONLY SHOWS A SLOW BEND TO THE NORTH BY THE END OF THE FORECAST PERIOD. THE CENTER OF FAY WILL BE NEAR OR OVER WATER DURING THE NEXT 48 HOURS OR SO...WHILE ATMOSPHERIC CONDITIONS REMAIN CONDUCIVE TO SUPPORT A TROPICAL STORM. THERE IS NO OBVIOUS REASON TO FORECAST WEAKENING DURING THE NEXT DAY OR SO...GIVEN THAT FAY WILL REMAIN NEAR THE COAST AND APPEARS NOT LIKELY TO CHANGE MUCH IN STRUCTURE. BEYOND 24 HOURS...INCREASING LAND INTERACTION AND A GRADUAL RAMPING UP OF VERTICAL WIND SHEAR SHOULD INDUCE A WEAKENING TREND. THE NEW OFFICIAL FORECAST OF FAY TO REMAIN A TROPICAL STORM FOR THE NEXT COUPLE OF DAYS REQUIRES A WESTWARD EXTENSION OF THE COASTAL WATCHES AND WARNINGS. REGARDLESS OF ITS EXACT TRACK...FAY WILL BE MOVING RATHER SLOWLY DURING THE NEXT SEVERAL DAYS...POSING A SIGNIFICANT HEAVY RAINFALL AND FLOOD HAZARD TO A VERY LARGE AREA. FORECAST POSITIONS AND MAX WINDS INITIAL 23/0300Z 29.7N 84.2W 45 KT 12HR VT 23/1200Z 29.8N 85.3W 45 KT...NEAR COAST 24HR VT 24/0000Z 30.1N 86.9W 45 KT...OVER WATER 36HR VT 24/1200Z 30.5N 88.5W 40 KT...NEAR COAST 48HR VT 25/0000Z 30.5N 90.0W 35 KT...INLAND 72HR VT 26/0000Z 30.5N 91.0W 30 KT...INLAND 96HR VT 27/0000Z 31.5N 91.5W 25 KT...INLAND 120HR VT 28/0000Z 33.0N 90.5W 25 KT...REMNANT LOW $$ FORECASTER KNABB