000
WTNT43 KNHC 152033
TCDAT3
TROPICAL STORM BILL DISCUSSION NUMBER   2
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL   AL032009
500 PM AST SAT AUG 15 2009
 
SATELLITE IMAGERY INDICATES THAT THE DEPRESSION IN THE FAR EASTERN
ATLANTIC HAS CONTINUED TO BECOME BETTER ORGANIZED. THE CYCLONE IS
LARGE AND HAS NUMEROUS CYCLONICALLY-CURVED CONVECTIVE BANDS WITH
THE OUTFLOW PRIMARILY ON THE WESTERN SEMICIRCLE. DVORAK T-NUMBERS
HAVE INCREASED AND SUPPORT UPGRADING THE SYSTEM TO TROPICAL STORM
STATUS WITH AN INITIAL INTENSITY OF 35 KNOTS. BILL IS EXPECTED TO
REMAIN OVER WARM WATERS AND EMBEDDED WITHIN LIGHT SHEAR THROUGH THE
FORECAST PERIOD. STRENGTHENING IS INDICATED AND BILL IS EXPECTED TO
BECOME A HURRICANE IN 3 TO 4 DAYS. THIS IS CONSISTENT WITH THE
UPWARD INTENSITY TREND INDICATED BY THE GUIDANCE.

BILL IS IN THE DEEP TROPICS AND IS WELL-EMBEDDED WITHIN THE EASTERLY
TRADE WINDS. THE CYCLONE IS MOVING JUST SOUTH OF DUE WEST OR 265
DEGREES AT 14 KNOTS. IN GENERAL...NO SIGNIFICANT CHANGE IN THE
STEERING CURRENTS IS ANTICIPATED AND BILL SHOULD BEGIN TO TURN A
LITTLE MORE TO THE WEST-NORTHWEST AROUND THE PERIPHERY OF THE
SUBTROPICAL RIDGE IN A DAY OR SO...WITH LITTLE CHANGE IN FORWARD
SPEED. THERE HAS NOT BEEN A SIGNIFICANT CHANGE IN THE GUIDANCE...AND
THE BULK OF THE MODELS HAS BILL AS A HURRICANE JUST NORTH AND VERY
NEAR THE NORTHERN LEEWARD ISLANDS AND SO DOES THE OFFICIAL
FORECAST.
 
 
FORECAST POSITIONS AND MAX WINDS
 
INITIAL      15/2100Z 11.3N  35.2W    35 KT
 12HR VT     16/0600Z 11.2N  37.2W    35 KT
 24HR VT     16/1800Z 11.5N  40.0W    45 KT
 36HR VT     17/0600Z 12.0N  43.0W    50 KT
 48HR VT     17/1800Z 13.0N  46.0W    55 KT
 72HR VT     18/1800Z 14.5N  52.0W    60 KT
 96HR VT     19/1800Z 17.0N  58.0W    75 KT
120HR VT     20/1800Z 19.5N  63.5W    90 KT
 
$$
FORECASTER AVILA