Flhurricane.com - Central Florida Hurricane Center - Tracking Storms since 1995Hurricanes Without the Hype! Since 1995
The Atlantic is quiet
|
Show Selection: |
| #538968 (Received by flhurricane at: 4:50 AM 31.Aug.2012) TCDAT2 TROPICAL STORM LESLIE DISCUSSION NUMBER 4 NWS NATIONAL HURRICANE CENTER MIAMI FL AL122012 500 AM AST FRI AUG 31 2012 WATER VAPOR IMAGERY SUGGESTS THAT THE EASTERLY SHEAR THAT HAS BEEN AFFECTING LESLIE IS GRADUALLY SUBSIDING. THE STORM IS PRODUCING GOOD OUTFLOW IN ALL QUADRANTS...AND IT APPEARS THAT THE LOW-LEVEL CENTER HAS MIGRATED FARTHER INTO THE CONVECTIVE CANOPY. DVORAK ESTIMATES HAVE INCREASED TO T3.5 FROM BOTH TAFB AND SAB...AND THE INITIAL INTENSITY IS RAISED TO 55 KT. LESLIE IS CURRENTLY MOVING AT 285/14 KT...AND A WEST-NORTHWESTWARD MOTION SHOULD CONTINUE AS THE CYCLONE APPROACHES A BREAK IN THE SUBTROPICAL RIDGE OVER THE WESTERN ATLANTIC. THE RIDGE IS FORECAST TO NEARLY VANISH BY DAY 3 AS LESLIE BECOMES POSITIONED BETWEEN TWO MID/UPPER-LEVEL LOWS AND WELL TO THE SOUTH OF THE MID-LATITUDE WESTERLIES. BECAUSE OF THE COLLAPSE IN THE STEERING FLOW...LESLIE IS EXPECTED TO TURN NORTHWARD BUT SLOW DOWN CONSIDERABLY BY DAYS 4 AND 5. THE TRACK GUIDANCE IS IN GOOD AGREEMENT ON THIS SCENARIO... BUT THERE HAS BEEN A NOTICEABLE SOUTHWESTWARD SHIFT ON DAYS 4 AND 5. THE NEW NHC FORECAST IS THEREFORE SLOWER AND FARTHER WEST OF THE PREVIOUS FORECAST AT THE LATTER END OF THE FORECAST PERIOD... BUT IT IS STILL EAST OF THE MODEL CONSENSUS TVCA ON DAY 5. THE UPPER-LEVEL ENVIRONMENT AROUND LESLIE IS IMPROVING...AND THE GLOBAL MODELS SUGGEST THAT THE STORM SHOULD HAVE AN OUTFLOW PATTERN BENEFICIAL FOR STRENGTHENING FOR AT LEAST THE NEXT 3 DAYS. THE OFFICIAL FORECAST THEREFORE SHOWS STEADY INTENSIFICATION THROUGH 72 HOURS AND ACTUALLY ENDS UP A BIT HIGHER THAN THE INTENSITY GUIDANCE. THERE IS SOME DISAGREEMENT AMONG THE MODELS ON DAYS 4 AND 5...HOWEVER. THE OPERATIONAL GFS MAINTAINS A GOOD UPPER-LEVEL OUTFLOW PATTERN ON THOSE DAYS...WHILE THE ECMWF...UKMET...GFS ENSEMBLE MEAN...AND ECMWF ENSEMBLE MEANS ALL SHOW AN INCREASE IN SHEAR. THE NHC FORECAST HEDGES ON THE SCENARIO SHOWN BY THE MAJORITY OF THESE MODELS...AS WELL AS THE STATISTICAL-DYNAMICAL GUIDANCE...AND INDICATES SOME POSSIBLE WEAKENING ON DAYS 4 AND 5. FORECAST POSITIONS AND MAX WINDS INIT 31/0900Z 15.2N 47.8W 55 KT 65 MPH 12H 31/1800Z 16.1N 50.0W 65 KT 75 MPH 24H 01/0600Z 17.4N 52.7W 70 KT 80 MPH 36H 01/1800Z 18.6N 55.2W 80 KT 90 MPH 48H 02/0600Z 19.9N 57.4W 85 KT 100 MPH 72H 03/0600Z 23.0N 60.5W 90 KT 105 MPH 96H 04/0600Z 25.5N 62.0W 85 KT 100 MPH 120H 05/0600Z 27.0N 62.0W 80 KT 90 MPH $$ FORECASTER BERG |
