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#47044 (Received by flhurricane at: 11:08 PM 19.Sep.2005) TCDAT3 TROPICAL STORM RITA DISCUSSION NUMBER 9 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 11 PM EDT MON SEP 19 2005 RITA REMAINS JUST UNDER HURRICANE STRENGTH. THE STORM PRODUCED A MASSIVE BURST OF COLD CONVECTION NEAR THE CENTER DURING THE EVENING...AND RADAR IMAGERY INDICATED AN INCREASE IN BANDING. HOWEVER...THIS INCREASE IN ORGANIZATION HAS NOT YET PRODUCED SIGNIFICANT INTENSIFICATION. AN AIR FORCE RESERVE HURRICANE HUNTER HAS REPORTED MAXIMUM 700 MB FLIGHT-LEVEL WINDS OF 59 KT 39 N MI NORTHWEST OF OF THE CENTER...AND A CENTER DROPSONDE OF 992 MB WITH 33 KT SURFACE WINDS. BASED ON THE THIS...THE CENTRAL PRESSURE IS 990 MB...AND THE INITIAL INTENSITY REMAINS 60 KT. THE INITIAL MOTION IS A SOMEWHAT UNCERTAIN 285/12...UNCERTAIN BECAUSE THE SHORT-TERM MOTION SEEMS TO BE A LITTLE MORE TO THE LEFT. OTHER THAN THAT...THERE IS LITTLE CHANGE IN THE FORECAST PHILOSOPHY FOR THE FIRST 72 HR. A STRONG DEEP-LAYER RIDGE ALONG THE NORTHERN GULF COAST SHOULD STEER RITA ON A GENERAL WEST-NORTHWESTWARD TO WESTWARD TRACK...AND ALL GUIDANCE AGREES WITH THIS SCENARIO. AFTER 72 HR...THERE IS SOME DIVERGENCE IN THE HANDLING OF THE GULF COAST RIDGE. THE UKMET AND NOGAPS KEEP THE RIDGE SOMEWHAT FARTHER WEST...THUS FORECASTING RITA TO MOVE INTO THE LOWER OR MIDDLE TEXAS COASTS IN 4-5 DAYS TIME. THE GFDL AND GFS CALL FOR THE RIDGE TO MOVE FATHER EASTWARD AND FORECAST RITA TO MAKE LANDFALL ALONG THE MIDDLE TO UPPER TEXAS COAST. THE FORECAST TRACK AFTER 72 HR WILL COMPROMISE BETWEEN THESE TWO EXTREMES... CALLING FOR A LANDFALL ON THE MIDDLE TEXAS COAST. THE TRACK AFTER 72 HR IS ALSO A LITTLE SLOWER THAN THE GUIDANCE CONSENSUS DUE TO THE MODEL SPREAD. UP TO NOW...RITA HAS HAD PROBLEMS DEVELOPING A WELL-DEFINED INNER CORE. THIS MIGHT BE DUE TO EASTERLY SHEAR CAUSED BY THE STRONG UPPER-LEVEL HIGH TO THE EAST-NORTHEAST OF THE CYCLONE AND AN UPPER-LEVEL LOW TO THE SOUTH-SOUTHWEST. OTHER THAN THAT... CONDITIONS APPEAR FAVORABLE FOR STRENGTHENING...AND IT IS LIKELY THAT RITA WILL REACH HURRICANE STRENGTH IN A FEW HOURS. THE INTENSITY FORECAST FOLLOWS THE SHIPS AND FSU SUPERENSEMBLE... ALTHOUGH STRONGER THAN BOTH. THE GFDL CONTINUES TO FORECAST VERY RAPID INTENSIFICATION TO MAJOR HURRICANE STATUS OVER THE VERY WARM WATERS OF THE FLORIDA STRAITS. SO FAR THIS HAS NOT HAPPENED...BUT THE GFDL COULD BE RIGHT IF RITA ESTABLISHES A BETTER INNER CORE. THERE IS THUS A POSSIBILITY THAT RITA COULD BECOME A MAJOR HURRICANE BEFORE PASSING THE FLORIDA KEYS. IT SHOULD BE NOTED THAT THE GFDL CALLS FOR RITA TO PEAK IN 24 HOURS AND THEN SLOWLY WEAKENS THE STORM FOR THE REST OF THE NEXT FIVE DAYS. THIS IS LIKELY DUE TO THE SEA SURFACE TEMPERATURES AND OCEANIC HEAT CONTENT OF THE GULF OF MEXICO BEING LESS THAN THOSE IN THE FLORIDA STRAITS...EXCEPT IN THE LOOP CURRENT. THE INITIAL WIND RADII WERE REVISED BASED ON AIRCRAFT DATA. FORECASTER BEVEN FORECAST POSITIONS AND MAX WINDS INITIAL 20/0300Z 23.3N 77.8W 60 KT 12HR VT 20/1200Z 23.7N 79.5W 75 KT 24HR VT 21/0000Z 24.2N 82.1W 85 KT 36HR VT 21/1200Z 24.5N 84.9W 95 KT 48HR VT 22/0000Z 24.8N 87.4W 100 KT 72HR VT 23/0000Z 25.5N 91.5W 105 KT 96HR VT 24/0000Z 27.5N 94.0W 105 KT 120HR VT 25/0000Z 30.5N 96.0W 60 KT...INLAND |