TROPICAL STORM EARL DISCUSSION NUMBER  43
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL   AL072010
1100 PM EDT SAT SEP 04 2010

OVER THE PAST FEW HOURS THE WIND FIELD OF EARL HAS BECOME
INCREASINGLY ELONGATED AND THE STRONGEST WINDS ARE NOW WELL REMOVED
FROM THE CENTER.  DRY AIR ASSOCIATED WITH THE LARGE UPPER TROUGH
INTERACTING WITH EARL HAS BEEN ENTRAINED THROUGH THE SOUTHERN
SEMICIRCLE OF THE CYCLONE.  ALSO...THE EASTERN PORTION OF EARL/S
CIRCULATION IS NOW INVOLVED WITH A FRONTAL ZONE.  BASED ON ALL
OF THIS...EARL IS NOW DECLARED POST-TROPICAL...AND THIS WILL BE THE
LAST NHC ADVISORY ON EARL.  THE INITIAL INTENSITY IS HELD AT 55 KT
BASED ON SURFACE OBSERVATIONS.  WEAKENING IS EXPECTED AS EARL
COMPLETES THE EXTRATROPICAL TRANSITION PROCESS.

THE FORWARD SPEED HAS CONTINUED TO INCREASE...AND IS NOW 030/40.
THE GLOBAL MODELS ARE IN RELATIVELY GOOD AGREEMENT ON THE TRACK OF
POST-TROPICAL EARL NORTHEASTWARD ACROSS LABRADOR AND INTO THE
ATLANTIC OVER THE NEXT DAY OR SO.  EARL WILL THEN MOVE SLOWLY
NORTHWARD AND NORTHWESTWARD FOR A COUPLE OF DAYS AS IT BECOMES A
VERTICALLY STACKED COLD CORE CYCLONE BEFORE ACCELERATING EASTWARD
ACROSS THE NORTH ATLANTIC AND DISSIPATING IN 4 OR 5 DAYS. THE
OFFICIAL FORECAST IS BASED ON A BLEND OF THE GFS AND ECMWF.

EARL IS STILL PRODUCING TROPICAL STORM CONDITIONS OVER PORTIONS OF
ATLANTIC CANADA.  FOR FURTHER INFORMATION ON POST-TROPICAL EARL IN
CANADA...SEE PRODUCTS FROM ENVIRONMENT CANADA.

ADDITIONAL INFORMATION ON POST-TROPICAL EARL 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      05/0300Z 50.7N  59.2W    55 KT...POST-TROPICAL 
12HR VT     05/1200Z 52.9N  55.4W    40 KT...POST-TROP/EXTRATROP
24HR VT     06/0000Z 55.0N  52.0W    35 KT...POST-TROP/EXTRATROP
36HR VT     06/1200Z 57.0N  53.0W    35 KT...POST-TROP/EXTRATROP
48HR VT     07/0000Z 57.0N  55.0W    35 KT...POST-TROP/EXTRATROP
72HR VT     08/0000Z 54.0N  50.0W    35 KT...POST-TROP/EXTRATROP
96HR VT     09/0000Z 52.0N  36.0W    25 KT...POST-TROP/EXTRATROP
120HR VT     10/0000Z...DISSIPATED

$$
FORECASTER BRENNAN