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| #52692 (Received by flhurricane at: 10:58 PM 20.Oct.2005) TCDAT4 HURRICANE WILMA DISCUSSION NUMBER 23 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 11 PM EDT THU OCT 20 2005 REPORTS FROM A NOAA HURRICANE HUNTER AIRCRAFT BEFORE 00Z INDICATED THAT THE CENTRAL PRESSURE OF WILMA HAD RISEN TO 923 MB...AND THE MAXIMUM 700 MB FLIGHT-LEVEL WINDS HAD DECREASED TO 130-140 KT. SINCE THEN...SATELLITE IMAGERY SHOWS AN IMPROVED EYE PRESENTATION AND COOLING CLOUD TOPS AROUND THE CENTER..ALTHOUGH NOT ENOUGH TO JUSTIFY AN INCREASE IN INTENSITY. BASED ON THIS...THE INITIAL INTENSITY REMAINS 130 KT. THE NEXT AIRCRAFT WILL INVESTIGATE WILMA AROUND 05Z. WILMA HAS TURNED MORE TO THE RIGHT DURING THE PAST FEW HR...WITH THE INITIAL MOTION NOW 325/5. THE HURRICANE IS MOVING INTO A COL AREA BETWEEN MID-LEVEL RIDGES TO THE EAST AND WEST...WHILE THE STRONGER WESTERLIES REMAIN NORTH OF 26N ACCORDING TO DATA FROM THE NOAA G4 JET. THIS IS A GOOD FORMULA FOR SLOW MOTION...AND ALL MODELS AGREE ON THIS FOR THE NEXT 24-48 HR. HOWEVER...THE DYNAMICAL MODELS STEER WILMA NORTHWESTWARD INTO THE YUCATAN PENINSULA DURING THE NEXT 12-24 HR...A MOTION THAT IS NOT SUPPORTED BY THE CURRENT RIGHT TURN OR THE JET DATA. THEREFORE...THE FORECAST TRACK WILL BE WELL TO THE RIGHT OF THE MODEL GUIDANCE...WITH THE CENTER FORECAST TO PASS OVER THE EXTREME NORTHEASTERN TIP OF THE YUCATAN PENINSULA. THIS TRACK ALSO REQUIRES AN EARLIER RECURVATURE INTO THE WESTERLIES THAN ANY OF THE GUIDANCE AND A FASTER PROGRESS TOWARD THE NORTHEAST AND THE FLORIDA PENINSULA. THE NEW FORECAST TRACK IS SIMILAR TO THE PREVIOUS FORECAST...EXCEPT SOMEWHAT SLOWER THROUGH 96 HR. GIVEN THE RADICAL DEPARTURE FROM THE MODEL GUIDANCE...THIS IS A LOW CONFIDENCE FORECAST. THE INTENSITY FORECAST IS VERY PROBLEMATIC. FIRST...THE INTENSITY FORECAST CALLS FOR WEAKENING DUE TO PASSAGE OVER THE YUCATAN PENINSULA. IF WILMA MOVES AS FAR INLAND AS THE MODELS FORECAST... IT WILL WEAKEN CONSIDERABLY AND LIKELY BE MUCH WEAKER THAN FORECAST ALONG THE REST OF THE TRACK. ON THE OTHER HAND...IF THE EYE MOVES EAST OF THE TRACK THE HURRICANE WILL LIKELY STAY STRONGER THAN FORECAST...AT LEAST FOR THE FIRST 36-48 HR. SECOND...ALL AVAILABLE DATA SHOWS THAT THE OUTFLOW HAS DECREASED TO THE WEST AS WEAK WESTERLY FLOW IMPINGES ON WILMA. THIS WILL LIKELY NOT PREVENT THE INTENSIFICATION FORECAST DURING THE NEXT 24 HR...ALTHOUGH IT MAY BE A PRECURSOR TO THE SHEAR FORECAST TO AFFECT THE HURRICANE OVER THE GULF OF MEXICO. THIS SHEAR SHOULD CAUSE WILMA TO WEAKEN REGARDLESS OF HOW STRONG IT IS AFTER PASSING YUCATAN. THIRD...WATER VAPOR IMAGERY CONTINUES TO SHOW VERY DRY MID/UPPER-LEVEL AIR COVERING THE GULF OF MEXICO. AS WILMA INTERACTS WITH THE WESTERLIES...THIS AIR SHOULD BEGIN TO ENTRAIN INTO THE HURRICANE...AND INDEED THERE HAS BEEN SOME EROSION OF THE WESTERN SIDE OF THE CLOUD PATTERN DURING THE PAST 6 HR. FINALLY...WILMA SHOULD PASS OVER THE WARM LOOP CURRENT FOLLOWED BY COOLER WATERS NEAR THE FLORIDA PENINSULA. THE LATTER SHOULD AID THE SHEAR-INDUCED WEAKENING. GIVEN THE UNCERTAINTIES...THE INTENSITY FORECAST WILL CHANGE LITTLE FROM THE PREVIOUS ADVISORY. IT SHOULD BE NOTED THAT IF WILMA MISSES YUCATAN THERE IS A CHANCE THAT IN SPITE OF ALL THE NEGATIVE FACTORS IT COULD BE A MAJOR HURRICANE AT LANDFALL IN FLORIDA. NOAA BUOY 42003 IN THE EASTERN GULF OF MEXICO REPORTS THAT LARGE SWELLS GENERATED BY WILMA ARE PROPAGATING TOWARD PORTIONS OF THE NORTHERN GULF COAST...AND COULD REACH THE COAST ON FRIDAY. FORECASTER BEVEN FORECAST POSITIONS AND MAX WINDS INITIAL 21/0300Z 19.3N 86.0W 130 KT 12HR VT 21/1200Z 19.9N 86.4W 140 KT 24HR VT 22/0000Z 20.8N 87.0W 145 KT...INLAND 36HR VT 22/1200Z 21.5N 87.1W 120 KT...INLAND 48HR VT 23/0000Z 22.1N 86.7W 105 KT...OVER WATER 72HR VT 24/0000Z 23.5N 84.5W 95 KT 96HR VT 25/0000Z 27.5N 79.5W 65 KT 120HR VT 26/0000Z 38.5N 69.5W 60 KT...EXTRATROPICAL |
