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#47841 (Received by flhurricane at: 11:08 PM 22.Sep.2005) TCDAT3 HURRICANE RITA DISCUSSION NUMBER 22 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 11 PM EDT THU SEP 22 2005 FLIGHT LEVEL WIND DATA AND RADAR OBSERVATIONS FROM THE AIR FORCE HURRICANE HUNTER AIRCRAFT INDICATE THAT THE CONCENTRIC EYEWALL CYCLE MIGHT BE NEARING COMPLETION. THERE IS NOW ONLY A SINGLE FLIGHT LEVEL WIND MAXIMUM AT A RADIUS OF ABOUT 20 N MI...ASSOCIATED WITH THE OUTER EYEWALL THAT THE AIRCRAFT RADAR INDICATE IS SLOWLY CONTRACTING... WHILE THE INNER EYEWALL CONTINUES TO DETERIORATE. RECENT GOES INFRARED IMAGERY ALSO INDICATES THAT A COMPLETE RING OF VERY COLD CONVECTIVE TOPS...COLDER THAN -70C... NOW SURROUNDS THE EYE. THE CENTRAL PRESSURE HAS ONLY RISEN SLIGHTLY TO 917 MB AS MEASURED BY THE MOST RECENT DROPSONDE. RECENT FLIGHT LEVEL AND DROPSONDE WIND DATA DO NOT SUPPORT AN INTENSITY GREATER THAN ABOUT 110 KT...BUT GIVEN THE VERY LOW PRESSURE...THE INITIAL INTENSITY IS ADJUSTED ONLY SLIGHTLY DOWNWARD TO 120 KT. RITA IS ABOUT TO PASS OVER ANOTHER EDDY OF HIGH OCEAN HEAT CONTENT. COMBINING THIS WITH THE POSSIBLE CONTRACTION OF THE OUTER EYEWALL DURING THE NEXT SEVERAL HOURS...SOME RESTRENGTHENING IS FORECAST IN THE SHORT TERM. GRADUAL WEAKENING IS POSSIBLE LATER ON FRIDAY BEFORE LANDFALL DUE TO LESSER OCEAN HEAT CONTENT CLOSER TO THE COAST...AND TO THE POSSIBILITY OF SOME INCREASE IN THE WIND SHEAR. THE BOTTOM LINE IS THAT THE INTENSITY WILL LIKELY FLUCTUATE DURING THE NEXT 36 HOURS...AND RITA IS EXPECTED TO MAKE LANDFALL AS A MAJOR HURRICANE...AT LEAST CATEGORY THREE. ALTHOUGH RITA HAS WOBBLED WESTWARD DURING THE PAST COUPLE OF HOURS...THE OVERALL MOTION DURING THE PAST SEVERAL HOURS HAS REMAINED WEST-NORTHWESTWARD...ABOUT 300/9. THERE ARE NO CHANGES TO THE OFFICIAL TRACK FORECAST...SINCE THE VARIOUS DYNAMICAL MODELS STRADDLE THE PREVIOUS ADVISORY TRACK. RITA IS EXPECTED TO GRADUALLY TURN NORTHWESTWARD AND EVENTUALLY NORTHWARD AS THE HIGH TO ITS NORTH SLIDES EASTWARD. RITA IS FORECAST TO THEN ESSENTIALLY STALL IN ABOUT THREE DAYS IN THE AREA OF NORTHEASTERN TEXAS WHERE STEERING CURRENTS ARE FORECAST TO BECOME VERY WEAK. THIS SCENARIO POSES A GREAT RISK OF VERY HEAVY RAINFALL WELL INLAND AND FOR MANY DAYS AFTER LANDFALL. FORECASTER KNABB FORECAST POSITIONS AND MAX WINDS INITIAL 23/0300Z 26.2N 90.3W 120 KT 12HR VT 23/1200Z 27.0N 91.5W 125 KT 24HR VT 24/0000Z 28.4N 93.0W 120 KT 36HR VT 24/1200Z 29.8N 94.2W 115 KT...INLAND 48HR VT 25/0000Z 31.1N 94.7W 65 KT...INLAND 72HR VT 26/0000Z 33.0N 95.0W 35 KT...INLAND 96HR VT 27/0000Z 33.0N 95.0W 25 KT...INLAND 120HR VT 28/0000Z 33.0N 95.0W 25 KT...INLAND |