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#384954 (Received by flhurricane at: 10:35 PM 23.Oct.2010) TCDAT4 TROPICAL STORM RICHARD DISCUSSION NUMBER 13 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL192010 1100 PM EDT SAT OCT 23 2010 DATA FROM AN AIR FORCE RESERVE UNIT AIRCRAFT INDICATE THAT RICHARD IS GRADUALLY BECOMING BETTER ORGANIZED. THE PLANE MEASURED MAXIMUM FLIGHT-LEVEL WINDS OF 71 KT AT 925 MB...SURFACE SFMR WINDS OF 58-63 KT...AND A MINIMUM PRESSURE OF 995 MB. BASED UPON THESE DATA...THE INITIAL INTENSITY IS INCREASED TO 60 KT. A 2259 UTC SSM/IS OVERPASS SHOWED A MID-LEVEL EYE FEATURE...AND THE PLANE REPORTED A FORMATIVE 20-25 N MI EYEWALL WITH A ROUGHLY 12 N MI RADIUS OF MAXIMUM WIND. RECENT MICROWAVE IMAGES SUGGEST THAT THE TILT OF THE VORTEX MAY BE GRADUALLY LESSENING...THOUGH VARIOUS SHEAR ANALYSES INDICATE THAT RESIDUAL WESTERLY SHEAR REMAINS. THE INTENSITY FORECAST REMAINS A BIT CHALLENGING. THE INTENSITY GUIDANCE HAS COME INTO BETTER AGREEMENT OVER THE LAST FEW FORECAST CYCLES...CALLING FOR A LESSER AMOUNT OF INTENSIFICATION COMPARED TO EARLIER RUNS. THE CONTINUED PRESENCE OF RELATIVELY DRY MID- TO UPPER-LEVEL AIR NEAR THE STORM CIRCULATION AND A SOMEWHAT RAGGED SATELLITE APPEARANCE OF THE CYCLONE WOULD ARGUE IN FAVOR OF THIS TREND. ON THE OTHER HAND...BARRING ANY SIGNIFICANT INTERACTION WITH LAND...THE RECENT INCREASE IN ORGANIZATION AND THE DECREASING VERTICAL WIND SHEAR COULD PORTEND ADDITIONAL STRENGTHENING PRIOR TO LANDFALL IN BELIZE. IF RICHARD SURVIVES ITS PASSAGE OVER LAND... REGENERATION OVER THE GULF OF MEXICO IS UNLIKELY GIVEN THE PROHIBITIVELY HIGH SHEAR FORECAST BY GLOBAL MODELS. THE INTENSITY WAS INCREASED DURING THE FIRST PART OF THE FORECAST DUE TO CURRENT TRENDS...AND THE CURRENT INTENSITY FORECAST IS SLIGHTLY ABOVE THE SHIPS/LGEM OUTPUT FOR THE FIRST 24 HR AND IN GOOD AGREEMENT AFTER THAT. USING RECON FIXES...THE INITIAL MOTION ESTIMATE IS 285/06. THERE HAS BEEN VIRTUALLY NO CHANGE TO THE TRACK FORECAST. GLOBAL MODELS ARE IN EXCELLENT AGREEMENT THAT A MID-LEVEL RIDGE OVER THE GULF OF MEXICO SHOULD STEER RICHARD ON A GENERALLY WEST-NORTHWESTWARD COURSE DURING THE NEXT COUPLE OF DAYS...BRINGING THE CENTER OF THE CYCLONE CLOSE TO THE BAY ISLANDS EARLY TOMORROW AND INLAND OVER BELIZE LATE SUNDAY OR EARLY MONDAY. AFTER THAT...A WEAKENING RICHARD OR ITS REMNANTS...THEN A SHALLOWER SYSTEM...SHOULD TURN NORTHWESTWARD WITHIN THE LOW-LEVEL FLOW AS IT APPROACHES THE GULF OF MEXICO. FORECAST POSITIONS AND MAX WINDS INITIAL 24/0300Z 16.3N 84.6W 60 KT 12HR VT 24/1200Z 16.5N 85.9W 65 KT 24HR VT 25/0000Z 16.8N 87.7W 70 KT 36HR VT 25/1200Z 17.1N 89.4W 45 KT...INLAND 48HR VT 26/0000Z 17.5N 90.7W 30 KT...INLAND 72HR VT 27/0000Z 19.0N 93.0W 25 KT...OVER WATER 96HR VT 28/0000Z 21.0N 94.5W 20 KT...POST-TROP/REMNT LOW 120HR VT 29/0000Z...DISSIPATED $$ FORECASTER KIMBERLAIN |