000
WTNT42 KNHC 092054
TCDAT2
TROPICAL STORM GABRIELLE DISCUSSION NUMBER   9
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL   AL072007
500 PM EDT SUN SEP 09 2007
 
DROPSONDE AND FLIGHT-LEVEL WIND DATA FROM THE AIR FORCE
RECONNAISSANCE MISSION THAT DEPARTED GABRIELLE JUST PRIOR
TO LANDFALL SUGGESTED THAT THE MAXIMUM WINDS WERE LIKELY 50 KT OVER
WATER SOUTH OF CAPE LOOKOUT.  THE CENTER THEN MADE LANDFALL ALONG
THE CAPE LOOKOUT NATIONAL SEASHORE AT ABOUT 1545 UTC. SINCE THEN
THE NORTHERLY SHEAR HAS TAKEN ITS TOLL ON THE CYCLONE...AND THE
EXPOSED LOW-LEVEL CENTER HAS PROCEEDED NORTHWARD OVER EXTREME
EASTERN NORTH CAROLINA.  HOWEVER...THE HEAVIEST RAINFALL HAS
REMAINED ALONG THE IMMEDIATE COAST WELL TO THE SOUTH OF THE CENTER.

THE INITIAL INTENSITY IS 45 KT.  THE SHEAR IS EXPECTED TO PERSIST
DURING THE NEXT COUPLE OF DAYS AND THE OFFICIAL INTENSITY FORECAST
INDICATES SLIGHT WEAKENING...BUT MAINTAINS GABRIELLE AS A TROPICAL
STORM UNTIL IT IS ABSORBED BY AN EXTRATROPICAL LOW BY 72 HOURS.
HOWEVER...IF CONVECTION DOES NOT RE-DEVELOP NEAR THE CIRCULATION
CENTER DURING THE NEXT 12-24 HOURS...GABRIELLE COULD WEAKEN FASTER
THAN INDICATED BELOW.
 
THE INITIAL MOTION ESTIMATE IS 010/10. THE FORECAST PHILOSOPHY
REMAINS UNCHANGED AND GABRIELLE IS EXPECTED TO TURN NORTHEASTWARD
SOON AS IT MOVES AROUND THE DEEP-LAYER RIDGE OVER THE WESTERN
ATLANTIC AND INTO THE WESTERLIES. THE TRACK GUIDANCE REMAINS
TIGHTLY CLUSTERED AND THE NEW OFFICIAL FORECAST IS CLOSE TO...BUT
SLIGHTLY SOUTH OF...THE PREVIOUS ADVISORY.   
 
FORECAST POSITIONS AND MAX WINDS
 
INITIAL      09/2100Z 35.7N  76.1W    45 KT...INLAND
 12HR VT     10/0600Z 36.7N  74.9W    40 KT...OVER ATLANTIC
 24HR VT     10/1800Z 37.8N  72.6W    40 KT
 36HR VT     11/0600Z 38.9N  69.4W    40 KT
 48HR VT     11/1800Z 40.3N  65.5W    35 KT
 72HR VT     12/1800Z...ABSORBED BY EXTRATROPICAL LOW
 
$$
FORECASTER BROWN/KNABB