000 WTNT42 KNHC 162039 TCDAT2 POST-TROPICAL CYCLONE GERT DISCUSSION NUMBER 12 NWS NATIONAL HURRICANE CENTER MIAMI FL AL072011 500 PM AST TUE AUG 16 2011 IT HAS BEEN MORE THAN 12 HR SINCE GERT LAST PRODUCED SIGNIFICANT ORGANIZED CONVECTION...A TREND THAT IS LIKELY TO CONTINUE AS THE CENTER MOVES OVER INCREASING COLDER WATERS. IN ADDITION...AN ASCAT OVERPASS AT 1420 UTC WAS AMBIGUOUS...AT BEST...AS TO WHETHER A CLOSED CIRCULATION STILL EXISTED. BASED ON THIS INFORMATION...GERT IS DOWNGRADED TO A POST-TROPICAL CYCLONE. THE CYCLONE IS LIKELY TO PERSIST FOR ANOTHER 12 HR OR SO BEFORE WEAKENING TO A TROUGH IN DEEP-LAYER SOUTHWESTERLY FLOW. IT SHOULD BE NOTED THAT QUALITY CONTROL ON A REPORT OF 44-KT WINDS FROM SHIP WDC6923 SUGGESTS THE REPORTED WINDS ARE A LITTLE TOO HIGH. THE INITIAL INTENSITY IS THEREFORE IN LINE WITH THE ASCAT DATA. THIS IS THE LAST ADVISORY ON GERT FROM THE NATIONAL HURRICANE CENTER. ADDITIONAL INFORMATION ON THIS SYSTEM CAN BE FOUND IN HIGH SEAS FORECASTS ISSUED BY THE NATIONAL WEATHER SERVICE...UNDER AWIPS HEADER NFDHSFAT1 AND WMO HEADER FZNT01 KWBC. FORECAST POSITIONS AND MAX WINDS INIT 16/2100Z 39.5N 54.7W 35 KT 40 MPH...POST-TROPICAL 12H 17/0600Z 41.9N 50.8W 35 KT 40 MPH...POST-TROPICAL 24H 17/1800Z...DISSIPATED $$ FORECASTER BEVEN