000
WTPZ42 KNHC 072038
TCDEP2
 
TROPICAL STORM GILMA DISCUSSION NUMBER   3
NWS NATIONAL HURRICANE CENTER MIAMI FL       EP072012
200 PM PDT TUE AUG 07 2012

GILMA HAS CONTINUED TO BECOME BETTER ORGANIZED THIS AFTERNOON...WITH
A CONVECTIVE BAND WRAPPING MORE THAN HALFWAY AROUND THE CIRCULATION
CENTER.  THE LATEST SATELLITE INTENSITY ESTIMATES ARE 35 KT FROM
TAFB AND 45 KT FROM SAB.  BASED ON THIS...THE INITIAL INTENSITY IS
INCREASED TO A POSSIBLY CONSERVATIVE 40 KT.  THE CIRRUS OUTFLOW IS
GOOD IN THE WESTERN SEMICIRCLE AND POOR ELSEWHERE.

THE INITIAL MOTION IS NOW 290/10.  GILMA IS SOUTH OF A MID-LEVEL
RIDGE EXTENDING FROM THE SOUTHWESTERN UNITED STATES AND THE
HAWAIIAN ISLANDS.  THIS SHOULD ALLOW A WEST-NORTHWESTWARD TO
WESTWARD MOTION TO CONTINUE FOR 36-48 HR.  AFTER THAT TIME...THE
GLOBAL MODELS SUGGEST THAT A LARGE AREA OF BROAD LOW-LEVEL CYCLONIC
FLOW WILL DEVELOP OVER THE NORTHEASTERN PACIFIC...POSSIBLY IN
RESPONSE TO ATLANTIC TROPICAL STORM ERNESTO OR ITS REMNANTS
CROSSING MEXICO AND RE-DEVELOPING IN THE PACIFIC.  WHILE THE UKMET
STILL SHOWS GILMA TURNING EASTWARD IN RESPONSE TO THIS
DEVELOPMENT...THE OTHER GLOBAL MODELS HAVE COME INTO BETTER
AGREEMENT THAT GILMA WILL CONTINUE A SLOW WESTWARD TO
WEST-NORTHWESTWARD MOTION.  THE NEW FORECAST TRACK NOW CALLS FOR AN
ERRATIC WESTWARD DRIFT AFTER 72 HR AND IS NUDGED A LITTLE NORTH OF
THE PREVIOUS FORECAST.  THE FORECAST CONFIDENCE IS HIGH DURING THE
FIRST 36 HR...THEN DECREASES SIGNIFICANTLY AFTER THAT.
 
GILMA IS CURRENTLY OVER WATER OF NEAR 29C AND IN AN ENVIRONMENT OF
LIGHT EAST-NORTHEASTERLY VERTICAL WIND SHEAR.  WHILE THE UPPER-LEVEL
WINDS SHOULD BE FAVORABLE FOR DEVELOPMENT...THE STORM IS FORECAST
TO MOVE OVER DECREASING SEA SURFACE TEMPERATURES...REACHING WATERS
OF 26C IN ROUGHLY 48 HR.  AFTER THAT...A COMBINATION OF INCREASING
SHEAR AND DECREASING SEA SURFACE TEMPERATURES SHOULD CAUSE STEADY
WEAKENING.  THE NEW INTENSITY FORECAST CALLS FOR GILMA TO PEAK IN
36-48 HR...AND THEN AGAIN SHOWS A FASTER WEAKENING RATE AFTER THAT
TIME.  IF THE CURRENT DEVELOPMENT RATE CONTINUES...GILMA COULD
BECOME A HURRICANE BEFORE REACHING THE COOLER WATERS.
 
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  07/2100Z 15.1N 113.9W   40 KT  45 MPH
 12H  08/0600Z 15.7N 115.4W   50 KT  60 MPH
 24H  08/1800Z 16.4N 117.1W   55 KT  65 MPH
 36H  09/0600Z 16.9N 118.6W   60 KT  70 MPH
 48H  09/1800Z 17.2N 119.8W   60 KT  70 MPH
 72H  10/1800Z 17.5N 121.0W   55 KT  65 MPH
 96H  11/1800Z 18.0N 121.5W   45 KT  50 MPH
120H  12/1800Z 18.0N 122.0W   35 KT  40 MPH
 
$$
FORECASTER BEVEN