TS LARRY 8 P.M. DISCUSSION.............

[dixiebreeze]

TROPICAL STORM LARRY SPECIAL DISCUSSION NUMBER 1
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
8 PM EDT WED OCT 01 2003

SATELLITE IMAGERY OVER THE LAST 24 HOURS INDICATES THAT THE
CONVECTION IN THE GULF OF MEXICO HAS BEEN GRADUALLY CONSOLIDATING
AROUND THE LOW CENTER. DATA FROM THE AIR FORCE RESERVE UNIT
RECONNAISSANCE AIRCRAFT INVESTIGATING THE LOW INDICATE LITTLE OR NO
LOW LEVEL FRONTAL TEMPERATURE GRADIENT REMAINS. THE WIND FIELD IN
THE VICINITY OF THE LOW IS ALSO BECOMING MORE CIRCULAR WITH MINIMAL
WIND SHIFTS ALONG THE OLD FRONTAL BOUNDARIES. CONSEQUENTLY...THE
LOW CAN NOW REASONABLY BE CONSIDERED A TROPICAL CYCLONE. LARRY
STILL DOES NOT HAVE A PARTICULARLY WELL-DEFINED CENTER OF
CIRCULATION...WITH A NUMBER OF CONVECTIVELY-GENERATED SWIRLS MOVING
ABOUT A BROADER CENTER. THE INITIAL INTENSITY OF 45 KT IS BASED ON
PEAK FLIGHT-LEVEL WINDS OF 56 KT IN THE SOUTHWEST QUADRANT.

THE INITIAL MOTION IS DIFFICULT TO ASSESS GIVEN THE POOR DEFINITION
OF THE CENTER...BUT IS APPROXIMATELY STATIONARY. LARRY IS
CURRENTLY TRAPPED IN A WEAK STEERING FLOW BETWEEN MID-LEVEL RIDGES
TO ITS EAST AND WEST. A STRONG MID-LEVEL WESTERLY CURRENT WILL
DEVELOP OVER THE NORTHERN GULF OVER THE NEXT FEW DAYS...BUT IT IS
NOT CLEAR THAT LARRY WILL EVER FEEL ITS INFLUENCE. GLOBAL MODEL
GUIDANCE GENERALLY INDICATES LITTLE MOTION FOR THE NEXT COUPLE OF
DAYS...WITH PERHAPS A WESTWARD DRIFT AFTER THAT.

THE UPPER-LEVEL ENVIRONMENT IS FAVORABLE FOR DEVELOPMENT...BUT THE
INNER CORE STRUCTURE NEEDS TO DEVELOP SOME BEFORE RAPID
STRENGTHENING CAN OCCUR. THE OCEANIC HEAT CONTENT IN THE
SOUTHWESTERN GULF IS NOT OVERLY HIGH...SO IF LARRY STAYS IN ONE
SPOT FOR TOO LONG THIS WILL BE AN INHIBITING FACTOR. THE
THERMODYNAMIC ENVIRONMENT NORTH AND WEST OF THE CYCLONE IS ALSO NOT
CONDUCIVE FOR RAPID DEVELOPMENT. THE OFFICIAL FORECAST CALLS FOR A
SLOW STRENGTHENING TREND.

FORECASTER FRANKLIN