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#52920 (Received by flhurricane at: 11:03 PM 21.Oct.2005) TCDAT4 HURRICANE WILMA DISCUSSION NUMBER 27 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 11 PM EDT FRI OCT 21 2005 THE EYE OF WILMA IS SLOWLY MAKING LANDFALL ON THE NORTHEASTERN COAST OF THE YUCATAN PENINSULA. EVEN BEFORE LANDFALL...AN AIR FORCE RESERVE HURRICANE HUNTER AIRCRAFT INDICATED THAT THE FLIGHT-LEVEL WINDS WERE DECREASING AND THAT THE CENTRAL PRESSURE WAS STARTING TO RISE. SINCE THE PLANE LEFT...THERE HAS BEEN A NOTABLE DECREASE IN THE SATELLITE SIGNATURE WITH THE CONVECTIVE TOPS WARMING AND THE EYE BECOMING CLOUD FILLED. THERE WAS A SURFACE WIND OF 137 KT FROM AN EYEWALL DROPSONDE EAST OF THE CENTER AROUND 23Z. WHILE THIS SURFACE WIND IS NOT SUPPORTED BY EITHER THE FLIGHT-LEVEL WINDS OR THE NORMAL DROPSONDE ANALYSIS PROCEEDURES...IT AND A COUPLE OF 127 KT SURFACE WINDS FROM EARLIER DROPS SUGGEST THE POSSIBILITY THAT WILMA MIGHT HAVE BEEN A LITTLE STRONGER THAN 120 KT THIS AFTERNOON. BASED ON THIS AND THE DECAY SINCE THE PLANE LEFT...THE INITIAL INTENSITY REMAINS 120 KT. THE INITIAL MOTION IS A WOBBLY 330/3. WILMA IS CURRENTLY IN A COL AREA BETWEEN TWO SEGMENTS OF THE SUBTROPICAL RIDGE...AND SHOULD MOVE SLOWLY NORTH-NORTHWESTWARD OR NORTHWARD FOR THE NEXT 12-24 HR INTO THE GULF OF MEXICO. AFTER THAT TIME...A POWERFUL DEEP-LAYER TROUGH DEVELOPING OVER THE EASTERN UNITED STATES SHOULD BEGIN TO TURN THE HURRICANE NORTHEASTWARD WITH GRADUAL ACCELERATION. THE DYNAMICAL MODELS ARE IN BETTER AGREEMENT THAT WILMA WILL CROSS THE FLORIDA PENINSULA IN 60-72 HR...ALTHOUGH THE NOGAPS IS STILL A LITTLE SLOWER. HOWEVER...THERE IS SOME SPREAD AS TO WHICH PART OF FLORIDA THE CENTER WILL CROSS...WITH THE GFDL AND GFS POINTING MORE NORTHWARD TOWARDS CHARLOTTE HARBOR...AND THE UKMET AND ECMWF POINTING MORE TOWARD THE FLORIDA KEYS. THE OFFICIAL FORECAST TRACK IS SHIFTED A LITTLE TO THE RIGHT OF THE PREVIOUS TRACK FOR THE FIRST 96 HR...AND LIES ON THE RIGHT SIDE OF THE GUIDANCE ENVELOPE. GIVEN THE UNCERTAINTY OF WHERE THE CENTER WILL CROSS FLORIDA...ALL INTERESTS IN THE FLORIDA PENINSULA SHOULD CONTINUE TO MONITOR THE PROGRESS OF WILMA AND MAKE APPROPRIATE PREPARATIONS. THE INTENSITY FORECAST REMAINS PROBLEMATIC. THE FIRST QUESTION IS HOW STRONG WILL WILMA BE WHEN IT EMERGES INTO THE GULF OF MEXICO... A QUESTION COMPLICATED BY THE EYEWALL REPLACEMENT CYCLE IT IS UNDERGOING AS IT MAKES LANDFALL. SINCE THE NEW FORECAST TRACK CALLS FOR LESS TIME OVER YUCATAN THAN EARLIER...THE INTENSITY FORECAST HAS WILMA EMERGING OVER THE GULF AT A SLIGHTLY HIGHER INTENSITY THAN THE PREVIOUS ADVISORY. ONCE OVER THE GULF...THERE IS A WINDOW OF OPPORTUNITY FROM 24-48 HR FOR WILMA TO RE-INTENSIFY AS IT PASSES OVER THE LOOP CURRENT. AFTER 48 HR...THE LARGE-SCALE MODELS AGREE THAT VERTICAL SHEAR WILL INCREASE SIGNIFICANTLY OVER WILMA...WHICH WILL LIKELY CAUSE WEAKENING. THE INTENSITY FORECAST CALLS FOR WILMA TO REACH 95 KT BEFORE THE SHEAR HITS...AND IT WILL PROBABLY REACH FLORIDA AS A CATEGORY TWO HURRICANE. WILMA SHOULD WEAKEN DURING AFTER AFTER CROSSING FLORIDA...BECOMING EXTRATROPICAL OVER THE ATLANTIC BETWEEN 96-120 HR. FORECASTER BEVEN FORECAST POSITIONS AND MAX WINDS INITIAL 22/0300Z 20.8N 86.9W 120 KT 12HR VT 22/1200Z 21.2N 87.1W 100 KT...INLAND 24HR VT 23/0000Z 21.7N 87.2W 90 KT...OVER WATER 36HR VT 23/1200Z 22.3N 86.9W 95 KT 48HR VT 24/0000Z 23.5N 85.4W 95 KT 72HR VT 25/0000Z 27.0N 80.0W 65 KT 96HR VT 26/0000Z 35.0N 71.0W 55 KT...EXTRATROPICAL 120HR VT 27/0000Z 45.0N 59.0W 55 KT...EXTRATROPICAL |