000
WTNT43 KNHC 010232
TCDAT3
TROPICAL STORM CHANTAL DISCUSSION NUMBER   5
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL   AL032007
1100 PM EDT TUE JUL 31 2007
 
SATELLITE IMAGERY SUGGESTS THAT CHANTAL IS RAPIDLY BECOMING
EXTRATROPICAL.  THE CONVECTIVE BAND THAT WAS WRAPPING AROUND THE 
CENTER DURING THE AFTERNOON HAS WEAKENED THIS EVENING.  SATELLITE
INTENSITY ESTIMATES CONTINUE TO SUPPORT AN INITIAL INTENSITY OF 45
KT.  AS CHANTAL PASSED VERY NEAR BUOY 44912 AROUND 2300 UTC...THE
BUOY REPORTED A MINIMUM PRESSURE OF 995.1 MB.  THE GLOBAL MODELS
SUGGEST THAT THE SYSTEM WILL INTENSIFY INTO A POWERFUL
EXTRATROPICAL LOW OVER THE NORTH ATLANTIC DURING THE NEXT 2-3 
DAYS.  

THE INITIAL MOTION ESTIMATE IS 045/28.  THE TRACK GUIDANCE IS
TIGHTLY CLUSTERED ON A NORTHEASTWARD MOTION DURING THE DAY OR SO. 
ON THIS TRACK...EXTRATROPICAL CHANTAL IS EXPECTED TO PASS OVER OR
VERY NEAR THE AVALON PENINSULA OF NEWFOUNDLAND IN ABOUT 12 HOURS. 
BEYOND 72 HOURS...THE MODEL SPREAD IS MUCH GREATER...WITH THE ECMWF
SHOWING A SLOWER MOTION THAN EITHER THE GFS OR NOGAPS.  THE
OFFICIAL FORECAST IS CLOSE TO THE PREVIOUS ADVISORY AND IS NEAR THE
GFS GLOBAL MEAN ENSEMBLE.

THIS IS THE LAST ADVISORY ISSUED BY THE NATIONAL HURRICANE CENTER ON
CHANTAL.  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
 
INITIAL      01/0300Z 43.6N  58.5W    45 KT
 12HR VT     01/1200Z 46.6N  53.6W    45 KT...EXTRATROPICAL
 24HR VT     02/0000Z 51.7N  45.1W    45 KT...EXTRATROPICAL
 36HR VT     02/1200Z 56.0N  37.0W    50 KT...EXTRATROPICAL
 48HR VT     03/0000Z 57.9N  32.3W    60 KT...EXTRATROPICAL
 72HR VT     04/0000Z 60.0N  25.0W    50 KT...EXTRATROPICAL
 96HR VT     05/0000Z 62.0N  16.5W    40 KT...EXTRATROPICAL
120HR VT     06/0000Z 65.5N   8.0W    35 KT...EXTRATROPICAL
 
$$
FORECASTER BROWN