Flhurricane.com - Central Florida Hurricane Center - Tracking Storms since 1995Hurricanes Without the Hype! Since 1995
The Atlantic is quiet
|
Show Selection: |
| #450468 (Received by flhurricane at: 10:37 AM 16.Aug.2011) TCDAT2 TROPICAL STORM GERT DISCUSSION NUMBER 11 NWS NATIONAL HURRICANE CENTER MIAMI FL AL072011 ISSUED BY THE HYDROMETEOROLOGICAL PREDICTION CENTER CAMP SPRINGS MD 1100 AM AST TUE AUG 16 2011 GERT CONTINUES TO WEAKEN THIS MORNING...WITH THE ASSOCIATED THUNDERSTORM ACTIVITY VIRTUALLY EVAPORATING AROUND 10Z. MORNING SATELLITE IMAGERY...AND TO SOME DEGREE DETERMINISTIC MODEL GUIDANCE...IMPLIED THAT GERT HAS ABOUT 10 KNOTS OF NORTHEASTERLY VERTICAL WIND SHEAR DUE TO THE STRONGER SOUTHWESTERLY LOW-LEVEL FLOW CONFLICTING WITH LIGHTER SOUTHWEST WINDS AT THE 300 HPA LEVEL. THE LOW-LEVEL CENTER REMAINS EXPOSED...THOUGH NEW CONVECTION IS TRYING TO DEVELOP ON ITS NORTHEAST SIDE WHICH COULD BE AN INDICATION OF A SWITCH IN THE DIRECTION OF THE VERTICAL WIND SHEAR TO SOUTHWESTERLY...WHICH WAS PREVIOUSLY ANTICIPATED. THE INITIAL WIND SPEED HAS BEEN LOWERED TO 35 KT FOR THIS ADVISORY...IN LINE WITH THE CURRENT T-NUMBER FROM TAFB BUT HIGHER THAN THAT PROVIDED BY SAB. THIS SYSTEM STILL HAS A FEW MORE HOURS BEFORE IT CROSSES THE 26C ISOTHERM...WHICH SHOULD ALLOW IT TO RETAIN ITS CURRENT INTENSITY. GERT IS FORECAST TO BECOME A POST-TROPICAL CYCLONE IN ABOUT 12 HOURS AS IT MOVES OVER WATERS NEAR 20C AND INTERACTS WITH THE APPROACHINIG COLD FRONT...WHICH COULD LEAD TO TEMPORARY RESTRENGTHENING...SO THE INTENSITY FORECAST HAS BEEN LEFT RELATIVELY UNCHANGED. THE RESULTANT LOW PRESSURE AREA SHOULD LOSE DEFINITION WITHIN THE FRONTAL ZONE DURING THE DAY WEDNESDAY. THE TROPICAL STORM IS ACCELERATING INTO THE NORTH ATLANTIC WATERS...AND THE LATEST INITIAL MOTION ESTIMATE IS 040/26. THIS SYSTEM COULD ACCELERATE SLIGHTLY MORE AS GERT BECOMES INCREASINGLY STEERED BY THE STRONG LOW-LEVEL FLOW TO THE EAST OF A DEEP-LAYER TROUGH ALONG THE UNITED STATES EAST COAST. THE OFFICIAL FORECAST IS SLIGHTLY TO THE LEFT OF THE PREVIOUS ONE BUT REMAINS ON THE EASTWARD SIDE OF THE GUIDANCE ENVELOPE. THE FORECAST TRACK AND TIMING OF EXTRATROPICAL TRANSITION INCORPORATE IDEAS COMMUNICATED BY THE OCEAN PREDICTION CENTER. FORECAST POSITIONS AND MAX WINDS INIT 16/1500Z 38.1N 57.5W 35 KT 40 MPH 12H 17/0000Z 41.0N 54.2W 35 KT 40 MPH 24H 17/1200Z 44.3N 49.0W 40 KT 45 MPH...POST-TROP/EXTRATROP 36H 18/0000Z...POST-TROP/EXTRATROP $$ FORECASTER ROTH |
