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#53457 (Received by flhurricane at: 11:20 PM 23.Oct.2005) TCDAT4 HURRICANE WILMA DISCUSSION NUMBER 35 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 11 PM EDT SUN OCT 23 2005 WILMA HAS CONTINUED TO BECOME BETTER ORGANIZED THIS EVENING WITH THE LARGE 45 NMI DIAMETER BECOMING VERY DISTINCT IN BOTH SATELLITE AND RADAR IMAGERY. AIR FORCE RECON FOUND 700 MB FLIGHT-LEVEL WINDS OF 114 KT IN THE NORTHEAST QUADRANT AT 0104Z... WHICH EQUALS ABOUT 103 KT SURFACE WINDS. DOPPLER VELOCITY DATA FROM KEY WEST HAS ALSO BEEN AS HIGH AS 109 KT AT 12000 FT. THE CENTRAL PRESSURE HAS DECREASED TO 958 MB... OR ABOUT 104 KT USING A STANDARD PRESSURE-WIND RELATIONSHIP. BASED ON THIS WIND INFORMATION AND THE CONTINUED INCREASE IN THE EYEWALL CONVECTION... THE INITIAL INTENSITY HAS BEEN CONSERVATIVELY INCREASED TO 100 KT... OR CATEGORY THREE/MAJOR HURRICANE STATUS. A RECON VORTEX MESSAGE JUST HANDED TO ME NOW INDICATES THE PRESSURE HAS DECREASED TO 957 MB. THE INITIAL MOTION IS 050/16. DUE TO A SLIGHT NORTHWARD TILT... THE SURFACE CENTER HAS BEEN PLACED ABOUT ONE-TENTH OF A DEGREE SOUTH OF THE RECON POSITIONS. WILMA HAS INCREASED ITS FORWARD SPEED BY 4 KT DURING THE PAST 6 HOURS... AND CONTINUED ACCELERATION IS EXPECTED FOR THE NEXT 24 HOURS. WILMA WILL LIKELY BE MOVING AT FORWARD SPEEDS OF 20 KT OR GREATER WHEN IT REACHES THE SOUTHWESTERN FLORIDA COAST AND CROSSES OVER THE SOUTHERN FLORIDA PENINSULA. THE NHC MODEL GUIDANCE IS NOW TIGHTLY PACKED AROUND THE PREVIOUS FORECAST TRACK... SO NO SIGNIFICANT CHANGES WERE MADE OTHER THAN TO INCREASE FORWARD SPEED AT ALL TIMES... ESPECIALLY AFTER WILMA EMERGES OVER THE WESTERN ATLANTIC. IN THE SHORT TERM... WATER VAPOR IMAGERY... 00Z UPPER-AIR DATA... AND DROPSONDE DATA FROM THE NOAA G-IV JET AIRCRAFT INDICATE THE DEEP LAYER TROUGH OVER THE CENTRAL U.S. HAS EXTENDED ITS INFLUENCE INTO THE WESTERN AND CENTRAL GULF OF MEXICO. WESTERLY MID-LEVEL WINDS OF 15-20 KT ARE NOW IMPINGING ON THE WESTERN SIDE OF WILMA... SO A CONTINUED NORTHEASTWARD MOTION TOWARD THE SOUTHWEST FLORIDA COAST AND ACROSS THE SOUTHERN FLORIDA SEEMS LIKELY. THEREFORE... A TRACK FROM COLLIER COUNTY TO NEAR LAKE OKEECHOBEE AND EXITING PALM BEACH COUNTY DURING THE NEXT 18 HOURS SEEMS QUITE REASONABLE. HOWEVER... GIVEN THAT WILMA HAS A 40-50 NMI DIAMETER EYE... HURRICANE-FORCE WINDS WILL EXTEND WELL AWAY FROM WHERE THE EXACT CENTER PASSES. IN THE LONGER TERM... ONCE WILMA EMERGES OVER THE ATLANTIC... THE DEEP LAYER TROUGH IS FORECAST TO CONTINUE DIGGING SHARPLY SOUTHWARD OVER THE SOUTHEASTERN U.S. AND THE GULF OF MEXICO. THIS SHOULD ACT TO LIFT WILMA RAPIDLY NORTHEAST TO NORTH-NORTHEASTWARD AND CONTINUE TO ACCELERATE THE HURRICANE OFF THE U.S. EAST COAST... WITH A POSSIBLE SECOND LANDFALL OCCURRING OVER NOVA SCOTIA AS A POWERFUL AND VERY LARGE EXTRATROPICAL LOW PRESSURE SYSTEM. THE OFFICIAL FORECAST TRACK IS SIMILAR TO THE PREVIOUS FORECAST... AND IS CLOSE TO THE NHC GUNA CONSENSUS MODEL. NOW THAT WILMA HAS ACCELERATED NORTHEASTWARD... THE EFFECTS OF ANY UPPER-LEVEL SHEAR SHOULD BE MINIMIZED RIGHT UP UNTIL THE HURRICANE REACHES THE FLORIDA EAST COAST. THE VARIOUS GLOBAL MODELS INDICATE THE DUAL OUTFLOW CHANNELS SHOULD REMAIN INTACT UNTIL WILMA REACHES THE ATLANTIC OCEAN... WHICH FAVOR AT LEAST SUSTAINING THE CURRENT INTENSITY. EYES THIS LARGE ARE ALSO MORE STABLE AND ARE MORE RESISTANT TO VERTICAL SHEAR. AS SUCH... WILMA IS EXPECTED TO BE A MAJOR HURRICANE AT LANDFALL ALONG THE SOUTHWEST FLORIDA COAST EARLY MONDAY MORNING. HOWEVER... ANOTHER 5-KT INCREASE IN INTENSITY MAY OCCUR WHILE WILMA REMAINS OVER THE SLIGHTLY WARMER GULF LOOP CURRENT. GIVEN THE FAST FORWARD SPEED EXPECTED AS WILMA TRAVERSES THE SOUTHERN FLORIDA PENINSULA... LESS WEAKENING SHOULD OCCUR AS COMPARED TO TYPICAL HURRICANES MOVING OVER LAND. THEREFORE... WILMA IS EXPECTED TO BE A CATEGORY TWO HURRICANE WHEN IT REACHES THE FLORIDA EAST COAST. AFTER EMERGING OVER THE ATLANTIC... INCREASING VERTICAL SHEAR IN EXCESS OF 50 KT AND MERGER WITH A FRONTAL SYSTEM SHOULD RESULT IN WILMA TRANSITIONING INTO A SIGNIFICANT EXTRATROPICAL WINTER-TYPE STORM SYSTEM... WHICH MAY PRODUCE A LARGE GALE AREA ON THE WEST SIDE OF THE STORM THAT COULD AFFECT PORTIONS OF THE U.S. EAST COAST AND THE CANADIAN MARITIMES. FORECASTER STEWART FORECAST POSITIONS AND MAX WINDS INITIAL 24/0300Z 24.4N 83.7W 100 KT 12HR VT 24/1200Z 26.2N 81.2W 100 KT...INLAND SWRN FLORIDA 24HR VT 25/0000Z 30.2N 76.3W 75 KT...OVER ATLANTIC 36HR VT 25/1200Z 36.5N 69.9W 65 KT...BECOMING EXTRATROPICAL 48HR VT 26/0000Z 42.9N 64.7W 60 KT...EXTRATROPICAL 72HR VT 27/0000Z 48.0N 60.0W 55 KT...EXTRATROPICAL 96HR VT 28/0000Z 49.5N 49.5W 55 KT...EXTRATROPICAL 120HR VT 29/0000Z 50.0N 38.0W 55 KT...EXTRATROPICAL |