Flhurricane.com - Central Florida Hurricane Center - Tracking Storms since 1995Hurricanes Without the Hype! Since 1995
The Atlantic is quiet
|
Show Selection: |
| #457977 (Received by flhurricane at: 11:12 PM 08.Sep.2011) TCDAT4 TROPICAL STORM MARIA DISCUSSION NUMBER 10 NWS NATIONAL HURRICANE CENTER MIAMI FL AL142011 1100 PM AST THU SEP 08 2011 THE CLOUD PATTERN OF MARIA HAS STABILIZED THIS EVENING...ALBEIT IN A RATHER DISORGANIZED CONDITION. PATCHES OF CONVECTION ARE OCCURRING OVER THE NORTHERN SEMICIRCLE OF A BROAD AREA OF CYCLONIC ROTATION...WITH AN OVERALL INCREASE IN CONVECTIVE COVERAGE DURING THE PAST SEVERAL HOURS. DUE TO COMMUNICATIONS PROBLEMS...THE AIRCRAFT THAT INVESTIGATED MARIA WAS UNABLE TO TRANSMIT A FULL DATA SET. THEREFORE...IT WAS NOT DETERMINED WITH CERTAINTY WHETHER A WELL-DEFINED CLOSED CIRCULATION STILL EXISTED. HOWEVER...THE PLANE MEASURED A CENTRAL PRESSURE OF 1005 MB...SHOWING THAT AT THE VERY LEAST A LOW PRESSURE CENTER STILL EXISTED. BASED ON THIS...MARIA IS MAINTAINED AS A TROPICAL CYCLONE. THE INITIAL INTENSITY OF 35 KT IS BASED ON THE AIRCRAFT DATA AND RECENT BUOY REPORTS. THE INITIAL MOTION IS 275/18. THE DYNAMICAL MODELS FORECAST THE CYCLONE TO TURN WEST-NORTHWESTWARD DURING THE NEXT 12-24 HOURS TOWARD A WEAKNESS IN LOW/MID-LEVEL SUBTROPICAL RIDGE TO THE NORTH...A WEAKNESS POSSIBLY CAUSED BY AN UPPER-LEVEL LOW SEEN IN WATER VAPOR IMAGERY NEAR 23N61W. WHILE THE NEW FORECAST TRACK FOLLOWS THIS SCENARIO...THE CURRENT RAPID MOTION SUGGESTS THIS TURN WILL BE MORE GRADUAL THAN THE MODEL GUIDANCE IS FORECASTING...AND THUS THE FIRST PART OF THE NEW TRACK IS ON THE SOUTH SIDE OF THE GUIDANCE ENVELOPE. AFTER 24 HOURS...ALL OF THE GUIDANCE FORECASTS MARIA TO MOVE WEST-NORTHWESTWARD TO NORTHWESTWARD TOWARD THE WESTERN END OF THE SUBTROPICAL RIDGE AS A DEEP-LAYER TROUGH MOVES THROUGH THE SOUTHEASTERN UNITED STATES. AFTER SHIFTING TO THE LEFT FOR THE PREVIOUS ADVISORY...THE GUIDANCE FOR THE POST-24 HOUR PERIOD HAS SHIFTED TO THE RIGHT FOR THIS ADVISORY. THE END OF THE FORECAST TRACK WILL SHOW A SMALL RIGHT TURN...BUT STILL LIES TO THE LEFT OF THE CENTER OF THE GUIDANCE ENVELOPE. IT SHOULD BE NOTED THAT THE UKMET AND ECMWF MODELS ARE STILL TO THE WEST OF THE NEW FORECAST AT 120 HOURS. THE INTENSITY GUIDANCE HAS BECOME A BIT MORE BULLISH THIS EVENING...WITH THE SHIPS AND LGEM MODELS NO LONGER FORECASTING MARIA TO WEAKEN TO A DEPRESSION. INDEED...THE SHIPS MODEL SHOWS THE VERTICAL WIND SHEAR DECREASING TO LESS THAN 10 KT DURING THE NEXT 24 HOURS AND REMAINING THAT LIGHT THROUGH 96 HOURS. GIVEN THE PRESENCE OF THE UPPER-LEVEL LOW TO THE NORTHWEST AND THE FORECAST UPPER-LEVEL WIND PATTERNS OF THE VARIOUS MODELS...THAT MIGHT BE A BIT OPTIMISTIC. THE NEW INTENSITY FORECAST NOW CALLS FOR MARIA TO MAINTAIN A 35-KT INTENSITY FOR THE NEXT 24 HOURS...FOLLOWED BY GRADUAL STRENGTHENING THROUGH THE REST OF THE FORECAST PERIOD. THE NEW INTENSITY FORECAST IS NEAR THE LOWER EDGE OF THE INTENSITY FORECAST GUIDANCE. THE CHANGE IN THE INTENSITY FORECAST FOR THE FIRST 24 HOURS REQUIRES TROPICAL STORM WARNINGS FOR PORTIONS OF THE LEEWARD ISLANDS. FORECAST POSITIONS AND MAX WINDS INIT 09/0300Z 13.3N 54.6W 35 KT 40 MPH 12H 09/1200Z 13.5N 57.2W 35 KT 40 MPH 24H 10/0000Z 14.7N 60.4W 35 KT 40 MPH 36H 10/1200Z 16.3N 62.8W 40 KT 45 MPH 48H 11/0000Z 17.8N 65.2W 45 KT 50 MPH 72H 12/0000Z 21.0N 69.5W 50 KT 60 MPH 96H 13/0000Z 23.5N 73.0W 55 KT 65 MPH 120H 14/0000Z 26.0N 75.0W 60 KT 70 MPH $$ FORECASTER BEVEN |
