Show Selection: |
#535059 (Received by flhurricane at: 10:35 PM 17.Aug.2012) TCDAT3 TROPICAL STORM GORDON DISCUSSION NUMBER 10 NWS NATIONAL HURRICANE CENTER MIAMI FL AL082012 1100 PM AST FRI AUG 17 2012 A SERIES OF SSMIS MICROWAVE OVERPASSES FROM THE NAVY/NRL TC PAGE INDICATE THAT DEEP CONVECTIVE BANDING HAS DEVELOPED OVER THE SOUTHERN HALF OF GORDON. BASED ON THE IMPROVED CLOUD PATTERN...THE TAFB SATELLITE INTENSITY ESTIMATE...AND TWO EARLIER CIRA AMSU-A ESTIMATES OF 62 AND 70 KT...THE INITIAL INTENSITY IS INCREASED TO 60 KT. THE OCEAN IS WARM AND THE SHEAR IS RELATIVELY LOW...FOR AT LEAST THE NEXT 24 HOURS. SUBSEQUENTLY...GORDON COULD STILL BECOME A HURRICANE IN THE SHORT TERM ALTHOUGH THE INTENSITY FORECAST DOES NOT EXPLICITLY INDICATE STRENGTHENING. VERTICAL SHEAR IS FORECAST TO INCREASE SIGNIFICANTLY BY DAY 2 WHICH SHOULD INDUCE A WEAKENING TREND. GORDON SHOULD COMPLETE EXTRATROPICAL TRANSITION AROUND THE 72 HOUR PERIOD...AS INDICATED BY A MAJORITY OF THE GLOBAL MODELS AND THE FLORIDA STATE CYCLONE PHASE EVOLUTION DIAGRAM. THE NHC INTENSITY FORECAST IS BASED ON THE IVCN STATISTICAL-DYNAMICAL INTENSITY MODEL CONSENSUS AND REFLECTS DISSIPATION AT DAY 5. THE INITIAL MOTION IS ESTIMATED TO BE 090/16 KT...WITHIN THE MID- TO UPPER-LEVEL MID-LATITUDE WESTERLIES. GORDON SHOULD CONTINUE MOVING GENERALLY EASTWARD AT A RAPID CLIP THROUGH DAY 3 AS IT MOVES SOUTH OF A LARGER EXTRATROPICAL LOW SITUATED A FEW HUNDRED MILES WEST OF THE UNITED KINGDOM. THROUGH THE REMAINDER OF THE FORECAST PERIOD...GORDON SHOULD BE A WEAK POST-TROPICAL CYCLONE...AND IS EXPECTED TO DECREASE IN FORWARD SPEED BY DAY 5 IN RESPONSE TO THE LOW-LEVEL NORTHERLY FLOW PRODUCED BY HIGH PRESSURE TO THE WEST. THE OFFICIAL TRACK FORECAST IS VERY CLOSE TO THE PREVIOUS ADVISORY AND THE TVCA MULTI-MODEL CONSENSUS. FORECAST POSITIONS AND MAX WINDS INIT 18/0300Z 34.2N 42.1W 60 KT 70 MPH 12H 18/1200Z 34.1N 39.3W 60 KT 70 MPH 24H 19/0000Z 34.4N 35.3W 60 KT 70 MPH 36H 19/1200Z 35.2N 31.3W 55 KT 65 MPH 48H 20/0000Z 36.4N 27.4W 50 KT 60 MPH 72H 21/0000Z 39.0N 20.0W 40 KT 45 MPH...POST-TROP/EXTRATROP 96H 22/0000Z 39.0N 16.0W 35 KT 40 MPH...POST-TROP/EXTRATROP 120H 23/0000Z...DISSIPATED $$ FORECASTER ROBERTS |