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| #52785 (Received by flhurricane at: 11:07 AM 21.Oct.2005) TCDAT4 HURRICANE WILMA DISCUSSION NUMBER 25 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 11 AM EDT FRI OCT 21 2005 WHETHER DUE TO INTERACTION WITH LAND OR SOME OTHER FACTORS... THE WESTERN PORTION OF THE INNER CORE CONVECTION BRIEFLY WEAKENED EARLIER THIS MORNING... BUT THAT DID NOT LAST LONG. THE RING OF VERY DEEP CONVECTION HAS RECONSTITUTED AROUND THE ENTIRE 30 N MI WIDE EYE... WHICH HAS BECOME A LITTLE CLEARER AND WARMER IN SATELLITE IMAGERY. THE CANCUN RADAR DEPICTS A VERY SOLID OUTER EYEWALL OVER COZUMEL... AND THE INNER EYEWALL IS LIKELY WEAKER BUT PERHAPS NOT AS WEAK AS IT SEEMS ON RADAR DUE TO ATTENUATION. PASSIVE MICROWAVE OVERPASSES FROM AMSR-E AND AMSU DURING THE PAST FEW HOURS DEPICT THE OUTER EYEWALL AT A RADIUS OF ABOUT 45 N MI... AND EARLIER AIRCRAFT DATA CONTAIN WIND MAXIMA AT RADII OF ABOUT 20 AND 45 N MI. IT IS POSSIBLE THAT THE OUTER EYEWALL WILL CONTRACT AND LEAD TO INTENSIFICATION IN THE SHORT TERM... BUT EYEWALLS WITH THIS LARGE OF A DIAMETER SOMETIMES REMAIN STEADY-STATE. DVORAK INTENSITY ESTIMATES AT 12Z DID NOT QUITE SUPPORT THE CURRENT ADVISORY INTENSITY OF 125 KT... BUT THAT WAS BEFORE THE DEEP CONVECTIVE RING REFORMED. WILMA IS LOCATED IN BETWEEN A MID-LEVEL RIDGE CENTERED OVER WESTERN MEXICO AND A MORE EXTENSIVE RIDGE OVER THE SUBTROPICAL ATLANTIC. THE ATLANTIC RIDGE SEEMED TO HAVE MORE INFLUENCE UNTIL VERY RECENTLY... WHEN THE NORTH-NORTHWESTWARD MOTION SLOWED. THE INITIAL MOTION ESTIMATE IS NOW NORTHWESTWARD...325/4...AND THE SHORT TERM MOTION MIGHT BE EVEN SLOWER. 12Z UPPER-AIR DATA FROM THIS MORNING'S NOAA G-IV JET SURVEILLANCE MISSION INDICATE PERHAPS EVEN A LITTLE MORE RIDGING OVER THE GULF OF MEXICO THAN CONTAINED IN THE SHORT-TERM FORECASTS FROM THE 06Z MODELS... SO THE SLOWER MOTION NOW OBSERVED IS NOT SURPRISING. NEARLY ALL OF THE DYNAMICAL MODELS FORECAST THE CENTER OF WILMA TO MAKE LANDFALL ON NORTHEASTERN YUCATAN TODAY... AS DOES THE OFFICIAL FORECAST. THE MODELS DO NOT AGREE ON HOW LONG WILMA WILL SPEND OVER LAND... AND THE NEW OFFICIAL FORECAST...WHILE ADJUSTED WESTWARD AND SLOWER THAN THE PREVIOUS ADVISORY THROUGH 48 HOURS...REMAINS TO THE EAST OF MOST OF THE MODELS AND KEEPS WILMA ON LAND FOR LESS THAN 18 HOURS. OBVIOUSLY... A LONGER STAY OVER YUCATAN COULD CAUSE MORE WEAKENING THAN FORECAST...BUT THE OPPOSITE IS ALSO TRUE. IN THE 3 TO 5 DAY TIME FRAME...THE NEW OFFICIAL FORECAST IS BASICALLY UNCHANGED. FORTUNATELY FOR THE SAKE OF BETTER AGREEMENT AMONG THE MODELS... THE NOGAPS NO LONGER KEEPS WILMA IN THE CARIBBEAN FOR FIVE DAYS AND IS NOW MORE IN LINE WITH THE REMAINING MODELS. THIS RESULTS IN THE DYNAMICAL CONSENSUS BEING IN FAIRLY GOOD AGREEMENT WITH THE PREVIOUS ADVISORY AT DAYS 3-5. HOWEVER... THE SPREAD IN THE MODELS REMAINS QUITE LARGE... AND BOTH THE LOCATION AND TIMING OF THE IMPACTS ON FLORIDA REMAIN VERY UNCERTAIN. THE NEW INTENSITY FORECAST IS VERY SIMILAR TO THE PREVIOUS ADVISORY IN STEADILY WEAKENING WILMA OVER THE GULF OF MEXICO DUE PRIMARILY TO INCREASING SHEAR. HOWEVER... IF WILMA DOES NOT SPEND MUCH TIME OVER YUCATAN... IT COULD BE STRONGER THAN FORECAST WHEN IT CROSSES FLORIDA. FORECASTER KNABB FORECAST POSITIONS AND MAX WINDS INITIAL 21/1500Z 20.2N 86.5W 125 KT 12HR VT 22/0000Z 20.8N 87.0W 135 KT...INLAND 24HR VT 22/1200Z 21.3N 87.4W 105 KT...INLAND 36HR VT 23/0000Z 21.8N 87.4W 105 KT 48HR VT 23/1200Z 22.3N 86.9W 100 KT 72HR VT 24/1200Z 24.5N 83.5W 90 KT 96HR VT 25/1200Z 29.5N 77.5W 65 KT 120HR VT 26/1200Z 39.0N 67.0W 60 KT...EXTRATROPICAL |
