000
WTPZ45 KNHC 312033
TCDEP5
TROPICAL STORM GIL DISCUSSION NUMBER  10
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL   EP102007
200 PM PDT FRI AUG 31 2007
 
ANIMATED INFRARED IMAGERY INDICATES THAT GIL IS UNDERGOING ANOTHER
LULL IN DEEP CONVECTION...CONSISTENT WITH A STRONGLY DIURNAL CYCLE
IN CONVECTIVE ACTIVITY. VISUAL DATA SHOWS A PARTIALLY EXPOSED LOW
LEVEL CENTER WITH WELL ORGANIZED CLOUD LINES. AN SSM/I SATELLITE
PASS AT 1317Z WAS ALSO USED TO LOCATE THE CENTER...WHICH HAS BEEN
ADJUSTED SLIGHTLY SOUTH OF THE PREVIOUS FORECAST TRACK. DVORAK
INTENSITY ESTIMATES AT 1800Z REMAIN AT 35 KT...SO WILL CONTINUE
WITH 35 KT AS THE INITIAL INTENSITY. WITHOUT ANY OTHER SUPPORTING
DATA...THE WIND RADII REMAIN THE SAME AS WELL.
 
GIL IS EXPECTED TO MAINTAIN ITS CURRENT INTENSITY FOR SEVERAL MORE
HOURS. EASTERLY VERTICAL SHEAR WILL CONTINUE TO AFFECT THE SYSTEM
OVER THE NEXT 24 TO 48 HOURS. ALTHOUGH THE T-NUMBER ESTIMATES ARE
LOWER THAN 12 HOURS AGO...THE DIURNAL PATTERN TO THE CONVECTION
SUGGESTS THEY WILL REBOUND TONIGHT...MATCHING THE CURRENT INTENSITY
VALUES ONCE AGAIN. BECAUSE THE FORECAST TRACK NEARLY PARALLELS THE
27C SST ISOTHERM...OCEAN TEMPERATURES SHOULD REMAIN A NEUTRAL
INFLUENCE. GIL IS ENTRAINING STABLE STRATOCUMULUS AIR FROM ITS
WESTERN FLANK INTO THE CORE. ALL INDICATIONS ARE IT WILL EITHER
MAINTAIN ITS CURRENT INTENSITY OR WEAKEN SLIGHTLY OVER THE NEXT 3
DAYS. THE OFFICIAL INTENSITY FORECAST IS CONSISTENT WITH THE
PREVIOUS ADVISORY.
 
THE INITIAL MOTION OF 270/9 IS THE SAME AS THE PREVIOUS ADVISORY...
AND THE TRACK FORECAST PHILOSOPHY IS UNCHANGED. TRACK GUIDANCE IS
IN GOOD AGREEMENT. GIL SHOULD CONTINUE ALONG A WESTWARD TRACK FOR
THE NEXT 24 HOURS...FOLLOWED BY A SLIGHT TURN TO THE WEST-NORTHWEST
AS IT NEARS THE WESTERN PERIPHERY OF THE SUBTROPICAL RIDGE. NONE
OF THE FORECAST AIDS ARE HINTING AT A RECURVATURE TRACK. ONCE GIL
WEAKENS TO A REMNANT LOW OVER COOLER WATERS...IT WILL BE STEERED
WESTWARD BY THE LOW LEVEL RIDGE.
 
FORECAST POSITIONS AND MAX WINDS
 
INITIAL      31/2100Z 18.9N 118.4W    35 KT
 12HR VT     01/0600Z 19.0N 120.1W    35 KT
 24HR VT     01/1800Z 19.3N 122.5W    35 KT
 36HR VT     02/0600Z 19.7N 124.7W    35 KT
 48HR VT     02/1800Z 20.1N 126.7W    30 KT
 72HR VT     03/1800Z 20.4N 131.0W    30 KT
 96HR VT     04/1800Z 20.5N 135.5W    25 KT...REMNANT LOW
120HR VT     05/1800Z 20.5N 139.5W    25 KT...REMNANT LOW
 
$$
FORECASTER MUNDELL/BLAKE