Show Selection: |
#43983 (Received by flhurricane at: 10:34 AM 04.Sep.2005) TCDAT4 HURRICANE MARIA DISCUSSION NUMBER 13 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 11 AM EDT SUN SEP 04 2005 THERE HAS BEEN NO SIGNIFICANT INCREASE IN THE ORGANIZATION OF THE CLOUD PATTERN...AND DVORAK T-NUMBERS FROM TAFB AND SAB REMAIN AT 4.0...CORRESPONDING TO A CURRENT INTENSITY OF 65 KT. MARIA HAS FAIRLY WELL-ESTABLISHED UPPER-LEVEL OUTFLOW...PARTICULARLY IN CHANNELS TO THE NORTHWEST AND SOUTHEAST. THE HURRICANE WILL CONTINUE TO TRAVERSE WARM WATERS SO STRENGTHENING IS LIKELY UNTIL WESTERLY VERTICAL SHEAR INCREASES SIGNIFICANTLY...WHICH IS EXPECTED TO OCCUR IN 48 HOURS OR SO. IN 4-5 DAYS...GLOBAL MODELS GUIDANCE SUGGESTS THAT MARIA WILL BE TRANSFORMING INTO A VIGOROUS EXTRATROPICAL CYCLONE. THE OFFICIAL INTENSITY FORECAST IS IDENTICAL TO THE PREVIOUS ONE. MOTION CONTINUES TOWARD THE NORTH-NORTHWEST...340/11. MARIA IS BEING STEERED BY THE FLOW ON THE SOUTHWEST PERIPHERY OF A MID-TROPOSPHERIC ANTICYCLONE OVER THE SUBTROPICAL EASTERN ATLANTIC. A 500 MB TROUGH CURRENTLY OVER THE NORTHEASTERN UNITED STATES IS FORECAST TO MOVE EASTWARD...AND APPROACH MARIA'S LONGITUDE WITHIN A COUPLE OF DAYS. THIS SHOULD CAUSE THE TROPICAL CYCLONE TO TURN NORTHWARD AND NORTHEASTWARD. THERE ARE SIGNIFICANT DIFFERENCES IN THE FORWARD SPEED AT 3-5 DAYS PREDICTED BY THE VARIOUS DYNAMICAL TRACK MODELS. SOME GUIDANCE...SUCH AS THE GFS...SHOW MARIA OR ITS EXTRATROPICAL VERSION BECOMING WELL EMBEDDED IN THE FLOW ASSOCIATED WITH THE TROUGH AND ACCELERATING EASTWARD. OTHER MODELS SUGGEST THAT THE TROUGH COULD BYPASS THE SYSTEM. THE OFFICIAL FORECAST IS A COMPROMISE OF THESE POSSIBILITIES AND SHOWS NO ACCELERATION THROUGH THE END OF THE PERIOD. THIS IS JUST SLIGHTLY TO THE RIGHT OF THE PREVIOUS ADVISORY FORECAST TRACK. FORECASTER PASCH FORECAST POSITIONS AND MAX WINDS INITIAL 04/1500Z 28.8N 55.5W 65 KT 12HR VT 05/0000Z 30.3N 56.1W 70 KT 24HR VT 05/1200Z 32.3N 56.4W 75 KT 36HR VT 06/0000Z 34.1N 56.1W 80 KT 48HR VT 06/1200Z 35.9N 54.7W 75 KT 72HR VT 07/1200Z 39.0N 50.5W 65 KT 96HR VT 08/1200Z 41.0N 45.5W 55 KT...BECOMING EXTRATROPICAL 120HR VT 09/1200Z 42.5N 40.0W 50 KT...EXTRATROPICAL |