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#43385 (Received by flhurricane at: 4:28 PM 31.Aug.2005) TCDAT3 TROPICAL STORM LEE DISCUSSION NUMBER 6 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 5 PM EDT WED AUG 31 2005 THERE IS AN UNCERTAINTY IN THE INTENSITY OF THE TROPICAL CYCLONE AT THIS TIME. HOWEVER...THE CLOUD PATTERN HAS BECOME A LITTLE BETTER ORGANIZED AND THE LOW-LEVEL CENTER IS ESTIMATED TO BE UNDER THE CONVECTION...BUT THE OUTFLOW IS LIMITED. BASED ON 2.5 DVORAK T-NUMBERS FROM TAFB AND SAB RESPECTIVELY AND AMSU ESTIMATES FROM CIMSS/NESDIS...THE INITIAL INTENSITY HAS BEEN INCREASED FROM 30 TO 35 KNOTS. THIS REQUIRES UPGRADING THE TROPICAL DEPRESSION TO TROPICAL STORM LEE...THE 12TH TROPICAL STORM OF THE 2005 SEASON. THE INTENSITY FORECAST CALLS FOR ONLY A SLIGHT STRENGTHENING SINCE THE OCEAN IS RELATIVELY WARM BUT THE UPPER-LEVEL ENVIRONMENT IS NOT VERY FAVORABLE. LEE IS MOVING TOWARD THE NORTH-NORTHEAST OR 020 DEGREES AT 12 KNOTS AROUND A MID-TO UPPER LEVEL LOW LOCATED TO THE NORTHWEST. THEREFORE...THE CYCLONE SHOULD TURN MORE TO THE NORTH AND NORTH-NORTHWEST WITH THE FLOW AROUND THE UPPER LOW AND A DECREASE IN FORWARD SPEED. THIS IS A SIGNIFICANT CHANGE FROM THE PREVIOUS FORECAST TRACK WHICH KEPT THE CYCLONE MOVING TOWARD THE NORTH NORTHEAST. THIS CHANGE IS BASED ON THE LASTEST RUN OF THE GLOBAL MODELS AND THE GFDL WHICH TAKE A LOW PRESSURE AREA...OR THE MODEL REPRESENTATION OF TROPICAL STORM LEE...AROUND THE LARGER UPPER-LOW AND A BUILDING HIGH PRESSURE OVER THE EASTERN NORTH ATLANTIC. ANY MOTION IS EXPECTED TO BE VERY SLOW. FORECASTER AVILA FORECAST POSITIONS AND MAX WINDS INITIAL 31/2100Z 30.5N 49.7W 35 KT 12HR VT 01/0600Z 32.3N 49.2W 40 KT 24HR VT 01/1800Z 34.0N 49.0W 40 KT 36HR VT 02/0600Z 35.0N 49.5W 40 KT 48HR VT 02/1800Z 36.0N 50.0W 40 KT 72HR VT 03/1800Z 37.0N 50.5W 35 KT 96HR VT 04/1800Z 38.0N 51.0W 30 KT 120HR VT 05/1800Z 39.0N 51.5W 25 KT...EXTRATROPICAL |