Skip Navigation Links
NOAA NOAA United States Department of Commerce

Tropical Depression GIL


ZCZC MIATCDEP5 ALL
TTAA00 KNHC DDHHMM
TROPICAL DEPRESSION GIL DISCUSSION NUMBER  11
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL   EP102007
800 PM PDT FRI AUG 31 2007
 
WHILE GIL CONTINUES TO GENERATE A CLUSTER OF DEEP CONVECTION WEST OF
THE CENTER...THE CONVECTIVE COVERAGE HAS DECREASED DURING THE PAST
24 HR...AND THE CONVECTION IS FARTHER FROM THE NOW EXPOSED
LOW-LEVEL CENTER.  SATELLITE INTENSITY ESTIMATES ARE 35 KT FROM
TAFB AND 30 KT FROM SAB.  BASED ON THIS AND THE OVERALL WEAKENED
APPEARANCE...GIL IS DOWNGRADED TO A 30 KT DEPRESSION.
 
THE INITIAL MOTION IS 265/8.  GIL IS ON THE SOUTH SIDE OF A
MID/UPPER-LEVEL RIDGE.  THE LARGE-SCALE MODELS FORECAST A WEAKNESS
IN THE RIDGE NORTHWEST OF GIL BY 72 HR...WHICH FILLS THEREAFTER. 
THIS WOULD ALLOW GIL TO TURN WEST-NORTHWESTWARD DURING THE NEXT 72
HR...WITH WHATEVER IS LEFT OF THE SYSTEM TURNING WESTWARD
THEREAFTER AS THE RIDGE BUILDS.  THE FORECAST TRACK FOLLOWS THIS
SCENARIO AND IS IN THE MIDDLE OF A SOMEWHAT SPREAD GUIDANCE SUITE.
 
THE FORECAST TRACK CALLS FOR GIL TO MOVE OVER DECREASING SEA SURFACE
TEMPERATURES...WITH THE TEMPERATURES UNDER THE CYCLONE DOWN TO 24C
BY 48 HR.  THIS SHOULD CAUSE WEAKENING EVEN THOUGH THE VERTICAL
WIND SHEAR IS FORECAST TO REMAIN LIGHT.  THE INTENSITY FORECAST
CALLS FOR GIL TO WEAKEN TO A REMNANT LOW IN ABOUT 72 HR...AND IT IS
POSSIBLE THIS COULD OCCUR EARLIER.
 
FORECAST POSITIONS AND MAX WINDS
 
INITIAL      01/0300Z 18.6N 119.0W    30 KT
 12HR VT     01/1200Z 18.7N 120.3W    30 KT
 24HR VT     02/0000Z 19.1N 122.4W    30 KT
 36HR VT     02/1200Z 19.5N 124.4W    30 KT
 48HR VT     03/0000Z 19.9N 126.3W    25 KT
 72HR VT     04/0000Z 20.0N 130.0W    20 KT...REMNANT LOW
 96HR VT     05/0000Z 20.0N 134.0W    20 KT...REMNANT LOW
120HR VT     06/0000Z 20.0N 137.5W    20 KT...REMNANT LOW
 
$$
FORECASTER BEVEN
 
NNNN