|
Show Selection: |
| #382256 (Received by flhurricane at: 10:37 AM 10.Oct.2010) TCDAT2 TROPICAL STORM OTTO DISCUSSION NUMBER 18 NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL172010 1100 AM AST SUN OCT 10 2010 RECENT SATELLITE IMAGERY SHOWS THE DEVELOPMENT OF FRONTAL CLOUD BANDS AND ALSO INDICATES THAT COOL DRY AIR HAS WRAPPED AROUND THE SOUTHERN SEMICIRCLE OF OTTO AND INTO THE CENTER. THE REMAINING CONVECTION IS NOW NORTH AND WEST OF THE CENTER AND AMSU TEMPERATURE PROFILES SHOW THAT THE UPPER-LEVEL WARM CORE HAS WEAKENED. BASED ON ALL OF THIS...OTTO IS NOW A POST-TROPICAL EXTRATROPICAL CYCLONE... AND THIS WILL BE THE LAST NHC ADVISORY. THE INITIAL INTENSITY IS HELD AT 55 KT...AND SLOW WEAKENING SHOULD BEGIN LATER TODAY AS OTTO MOVES AWAY FROM THE BEST BAROCLINIC DYNAMICS. GRADUAL WEAKENING IS EXPECTED TO CONTINUE FOR THE REST OF THE PERIOD. HOWEVER...IT IS WORTH NOTING THAT THE GFS AND ECMWF STRENGTHEN OTTO A LITTLE AT THE END OF THE PERIOD...SO THE OFFICIAL FORECAST COULD BE A LITTLE LOW ON DAYS 4 AND 5. OTTO IS RACING TOWARD THE NORTHEAST AT 35 TO 40 KNOTS...EMBEDDED WITHIN DEEP-LAYER SOUTHWESTERLY FLOW TO THE SOUTHEAST OF A LARGE MID/UPPER-LEVEL TROUGH CENTERED BETWEEN 55W AND 60W. THE GLOBAL MODELS ARE IN GENERALLY GOOD AGREEMENT IN SHOWING POST-TROPICAL OTTO ESCAPING THE WESTERN ATLANTIC TROUGH AND TURNING EASTWARD AND THEN SOUTHEASTWARD WITHIN 48 HOURS AS IT COMES UNDER THE INFLUENCE OF A DEEP-LAYER LOW CENTERED OVER THE IBERIAN PENINSULA AND WESTERN MEDITERRANEAN SEA. LATE IN THE PERIOD THE DEEP-LAYER LOW MOVES EAST...LEAVING OTTO BEHIND TO MOVE SLOWLY EASTWARD OR NORTHEASTWARD BY DAY 5. THE OFFICIAL FORECAST IS BASED ON A CONSENSUS OF THE GFS ...UKMET...ECMWF...AND CANADIAN GLOBAL MODELS. FUTURE INFORMATION ON POST-TROPICAL OTTO CAN BE FOUND IN HIGH SEAS FORECASTS ISSUED BY THE NATIONAL WEATHER SERVICE UNDER AWIPS HEADER NFDHSFAT1 AND WMO HEADER FZNT01 KWBC...AND BY METEO-FRANCE UNDER WMO HEADER FQNT50 LFPW. FORECAST POSITIONS AND MAX WINDS INITIAL 10/1500Z 37.3N 41.1W 55 KT...POST-TROP/EXTRATROP 12HR VT 11/0000Z 40.0N 35.6W 50 KT...POST-TROP/EXTRATROP 24HR VT 11/1200Z 42.6N 29.7W 45 KT...POST-TROP/EXTRATROP 36HR VT 12/0000Z 43.0N 26.3W 45 KT...POST-TROP/EXTRATROP 48HR VT 12/1200Z 41.5N 24.1W 40 KT...POST-TROP/EXTRATROP 72HR VT 13/1200Z 37.0N 22.0W 35 KT...POST-TROP/EXTRATROP 96HR VT 14/1200Z 36.0N 20.5W 30 KT...POST-TROP/EXTRATROP 120HR VT 15/1200Z 37.0N 19.5W 30 KT...POST-TROP/EXTRATROP $$ FORECASTER BRENNAN |
