000 WTNT42 KNHC 260849 TCDAT2 HURRICANE GUSTAV DISCUSSION NUMBER 5 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL072008 500 AM EDT TUE AUG 26 2008 GUSTAV HAS CONTINUED TO INTENSIFY DURING THE LATE NIGHT HOURS. AN AIR FORCE RESERVE RECONNAISSANCE MISSION HAS FOUND FLIGHT-LEVEL WINDS OF 90 KT...PEAK SFMR SURFACE WINDS OF 76 KT...AND A RECENT ESTIMATED PRESSURE OF 984 MB. THE INITIAL INTENSITY IS CONSERVATIVELY RAISED TO 75 KT. SATELLITE IMAGES SHOW AN ORGANIZING PATTERN WITH A CENTRAL DENSE OVERCAST BECOMING MORE PROMINENT AND GUSTAV IS LIKELY NOT DONE INTENSIFYING BEFORE IT PASSES OVER SOUTHWESTERN HAITI LATER TODAY. SOME WEAKENING IS SHOWN IN 24 HR DUE TO THE LAND INTERACTION WITH HAITI. THEREAFTER...THE HURRICANE IS FORECAST TO BE OVER EXTREMELY WARM WATERS WITH RELATIVELY LIGHT SHEAR. THE OFFICIAL INTENSITY FORECAST IS INCREASED AND NOW CALLS FOR GUSTAV TO BE A MAJOR HURRICANE IN THE NORTHWESTERN CARIBBEAN SEA. IT IS WORTH NOTING THAT BOTH THE GFDL/HWRF FORECAST SHOW AN EVEN STRONGER HURRICANE. MOST INDICATIONS ARE THAT GUSTAV WILL BE AN EXTREMELY DANGEROUS HURRICANE IN THE NORTHWESTERN CARIBBEAN SEA IN A FEW DAYS. THE INITIAL MOTION ESTIMATE IS 315/8...THOUGH GUSTAV MAY RECENTLY BE MOVING A BIT MORE TO THE RIGHT. THE BIGGEST CHANGE TO NOTE THIS MORNING IS A DRAMATIC SOUTHWESTWARD SHIFT WITH ALMOST ALL GUIDANCE. A LARGE UPPER TROUGH OVER THE WESTERN ATLANTIC IS EXPECTED TO MOVE EAST AWAY FROM GUSTAV...LEAVING RIDGING OVER THE BAHAMAS AND FLORIDA. GLOBAL MODELS HAVE COME INTO MUCH BETTER AGREEMENT THAT THE HURRICANE WILL TURN TO THE WEST-NORTHWEST OR EVEN WEST IN A DAY OR SO DUE TO THIS BUILDING RIDGE. THE OFFICIAL FORECAST HAS BEEN ADJUSTED SOUTHWESTWARD BEYOND 24 HR BUT IS STILL ON THE NORTHERN EDGE OF THE GUIDANCE ENVELOPE. THE FORECAST COULD HAVE BEEN SHIFTED EVEN MORE TO THE LEFT BUT WE'D PREFER TO WAIT UNTIL THE GUIDANCE BECOMES MORE STABLE. FORECAST POSITIONS AND MAX WINDS INITIAL 26/0900Z 17.2N 71.9W 75 KT 12HR VT 26/1800Z 18.0N 72.9W 85 KT 24HR VT 27/0600Z 18.8N 74.3W 75 KT 36HR VT 27/1800Z 19.2N 75.6W 80 KT 48HR VT 28/0600Z 19.4N 76.9W 85 KT 72HR VT 29/0600Z 20.0N 79.3W 90 KT 96HR VT 30/0600Z 21.0N 82.0W 100 KT 120HR VT 31/0600Z 23.0N 85.5W 100 KT $$ FORECASTER BLAKE/AVILA