|
Show Selection: |
| #519662 (Received by flhurricane at: 10:44 AM 20.Jun.2012) TCDAT3 TROPICAL STORM CHRIS DISCUSSION NUMBER 4 NWS NATIONAL HURRICANE CENTER MIAMI FL AL032012 1100 AM AST WED JUN 20 2012 THE SATELLITE APPEARANCE OF CHRIS HAS IMPROVED SINCE YESTERDAY. THE TROPICAL CYCLONE HAS BECOME MORE SYMMETRIC WITH SEVERAL BANDS OF SHOWERS WRAPPING AROUND THE CENTER. THE LATEST DVORAK INTENSITY ESTIMATE FROM TAFB AND RECENT UW/CIMSS ADVANCED DVORAK TECHNIQUE T-NUMBERS SUPPORT AN INITIAL WIND SPEED OF 45 KT. ENVIRONMENTAL CONDITIONS ARE EXPECTED TO REMAIN MARGINALLY CONDUCIVE FOR SOME SLIGHT STRENGTHENING DURING THE NEXT 12-18 HOURS. AFTER THAT TIME...CHRIS WILL BE INTERACTING WITH A FRONTAL BOUNDARY AND MOVING OVER MUCH COLDER WATERS. HOWEVER...THE GLOBAL MODELS INDICATE THAT THE CYCLONE WILL INITIALLY MAINTAIN ITS STRENGTH AS AN EXTRATROPICAL CYCLONE...BEFORE WEAKENING IN 2-3 DAYS. RECENT RUNS OF THE GLOBAL MODELS SUGGEST THAT THE POST-TROPICAL LOW COULD REMAIN THE DOMINANT SYSTEM AND NOT BE THE ONE ABSORBED BY ANOTHER EXTRATROPICAL LOW. FOR NOW THE NHC FORECAST WILL CONTINUE TO CALL FOR POST-TROPICAL CHRIS TO BE ABSORBED...BUT CHANGES TO THIS SCENARIO MAY BE REQUIRED IF MODEL TRENDS CONTINUE. CHRIS APPEARS TO HAVE TURNED EASTWARD WITH AN INITIAL MOTION OF 090/19 KT. THE OFFICIAL FORECAST REASONING REMAINS UNCHANGED FROM THE PREVIOUS ADVISORY. CHRIS IS EXPECTED TO TURN TOWARD THE NORTHEAST...THEN NORTHWARD WITHIN THE NEXT 24-36 HOURS AS A CLOSED LOW FORMS OVER THE NORTH ATLANTIC. LATER IN THE PERIOD...THE POST-TROPICAL CYCLONE IS FORECAST TO ROTATE CYCLONICALLY AROUND THE UPPER-LEVEL LOW. THE NHC FORECAST IS CLOSE TO THE GFS... ECMWF...AND ON THE POST-TROPICAL PORTION OF THE TRACK PROVIDED BY THE NOAA OCEAN PREDICTION CENTER. FORECAST POSITIONS AND MAX WINDS INIT 20/1500Z 38.1N 51.3W 45 KT 50 MPH 12H 21/0000Z 38.6N 47.6W 50 KT 60 MPH 24H 21/1200Z 40.5N 43.3W 45 KT 50 MPH 36H 22/0000Z 43.6N 41.8W 45 KT 50 MPH...POST-TROP/EXTRATROP 48H 22/1200Z 45.0N 43.2W 40 KT 45 MPH...POST-TROP/EXTRATROP 72H 23/1200Z 43.0N 45.5W 30 KT 35 MPH...POST-TROP/EXTRATROP 96H 24/1200Z...ABSORBED BY A LARGER EXTRATROPICAL LOW $$ FORECASTER BROWN |
