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#451616 (Received by flhurricane at: 10:58 AM 20.Aug.2011) TCDAT3 TROPICAL STORM HARVEY DISCUSSION NUMBER 7 NWS NATIONAL HURRICANE CENTER MIAMI FL AL082011 1000 AM CDT SAT AUG 20 2011 REPORTS FROM AN AIR FORCE RESERVE HURRICANE HUNTER AIRCRAFT INDICATE THAT HARVEY HAS CHANGED LITTLE IN STRENGTH DURING THE PAST FEW HOURS....WITH THE INTENSITY REMAINING NEAR 50 KT. THE AIRCRAFT REPORTED 61-KT 850 MB FLIGHT-LEVEL WINDS JUST NORTHEAST OF THE CENTER...WITH RELIABLE-LOOKING SFMR WINDS IN THE 45-50 KT RANGE. THE CENTRAL PRESSURE ON THE LAST FIX WAS NEAR 998 MB. DATA FROM THE RADAR AT BELIZE CITY SHOWS SOME CONVECTIVE BANDING IN THE SOUTHERN SEMICIRCLE...BUT THERE IS NO CLOSED EYEWALL APPARENT AT THIS TIME. THE CENTER JOGGED TO THE NORTHWEST EARLY THIS MORNING. HOWEVER...A MORE WESTWARD MOTION HAS RESUMED AND THE INITIAL MOTION FOR THIS ADVISORY IS 280/10. THE SUBTROPICAL RIDGE NORTH OF HARVEY IS EXPECTED TO STEER IT GENERALLY WESTWARD INTO BELIZE DURING THE NEXT SEVERAL HOURS...WITH A CONTINUED WESTWARD MOTION THEREAFTER UNTIL THE CYCLONE EVENTUALLY DISSIPATES. THE NEW FORECAST TRACK IS IN THE MIDDLE OF THE GUIDANCE ENVELOPE NEAR THE VARIOUS CONSENSUS MODELS. HARVEY HAS AT BEST 4-8 HOURS LEFT TO STRENGTHEN BEFORE LANDFALL. WHILE THE CHANCES OF THE CYCLONE REACHING HURRICANE STRENGTH ARE DIMINISHING...THE INNER WIND CORE IS SMALL AND THUS A 10-15 KT INCREASE IN STRENGTH CANNOT BE RULED OUT. HARVEY SHOULD WEAKEN AFTER LANDFALL...EVENTUALLY DISSIPATING OVER THE MOUNTAINS OF SOUTHEASTERN MEXICO BETWEEN 48-72 HOURS. FORECAST POSITIONS AND MAX WINDS INIT 20/1500Z 16.8N 87.6W 50 KT 60 MPH 12H 21/0000Z 17.0N 89.0W 45 KT 50 MPH...INLAND 24H 21/1200Z 17.3N 91.1W 30 KT 35 MPH...INLAND 36H 22/0000Z 17.6N 93.4W 25 KT 30 MPH...INLAND 48H 22/1200Z 17.7N 95.6W 20 KT 25 MPH...POST-TROP/REMNT LOW 72H 23/1200Z...DISSIPATED $$ FORECASTER BEVEN |