[Tropical] Tropical Cyclone Discussion

[EMWIN Server]

WTNT42 KNHC 301500
TCDAT2
HURRICANE GUSTAV DISCUSSION NUMBER  23
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL   AL072008
1100 AM EDT SAT AUG 30 2008

AFTER RAPIDLY INTENSIFYING OVERNIGHT...THE STRENGTHENING RATE
APPEARS TO HAVE SLOWED A LITTLE...ALTHOUGH THE CENTRAL PRESSURE
REPORTED BY RECON HAS CONTINUED TO FALL THIS MORNING...WITH THE
MOST RECENT VALUE DOWN TO 954 MB.  THE BRIEF TIME GUSTAV WILL SPEND
OVER WESTERN CUBA DURING THE NEXT DAY OR SO SHOULD NOT WEAKEN THE
HURRICANE MUCH...AND ALL INTENSITY GUIDANCE INDICATES CONDITIONS
ARE CONDUCIVE OVER THE GULF OF MEXICO FOR ADDITIONAL
STRENGTHENING...ESPECIALLY OVER THE SOUTHERN GULF WHERE OCEANIC
HEAT CONTENT IS GREATEST.  THE NEW OFFICIAL INTENSITY FORECAST
PEAKS A LITTLE HIGHER AT 120 KT...VERY CLOSE TO A CONSENSUS OF THE
AVAILABLE MODELS.  DESPITE THE IMPLIED WEAKENING BETWEEN 48 AND 72
HOURS DUE TO FORECAST LANDFALL...NO DRAMATIC WEAKENING IS FORECAST
WHILE GUSTAV REMAINS OVER THE GULF...AND IT COULD REACH THE
NORTHERN GULF COAST AS A MAJOR HURRICANE.

GUSTAV JOGGED NORTHWARD DURING THE PAST FEW HOURS...AND IT IS NOT
YET CLEAR IF IT HAS RESUMED A NORTHWESTWARD HEADING...BUT THE
LONG-TERM MOTION ESTIMATE IS NORTHWESTWARD OR 320/12.  THE STEERING
CURRENTS PUSHING GUSTAV NORTHWESTWARD ARE GENERALLY WELL-DEFINED
AND SHOULD REMAIN THAT WAY FOR AT LEAST THE NEXT COUPLE OF
DAYS...AS THE HURRICANE MOVES AROUND THE WESTERN PERIPHERY OF A
MID-LEVEL RIDGE OVER THE WESTERN ATLANTIC.  BEYOND 48 HOURS...MOST
OF THE GUIDANCE INDICATES A SLOWING OF THE FORWARD MOTION AS A
STRONG BUT DISTANT RIDGE BUILDS OVER THE NORTHEASTERN UNITED STATES
AND STEERING CURRENTS WEAKEN OVER THE GULF COAST STATES.  NONE OF
THE MODELS HAVE SIGNIFICANTLY CHANGED THEIR TRACK SOLUTION COMPARED
TO THE PREVIOUS CYCLE...SO THE CONSENSUS HAS REMAINED IN PLACE.
THE SPREAD AT 3-5 DAYS IS STILL SUBSTANTIAL...HOWEVER...WITH SOME
MODELS INCLUDING THE UKMET AND HWRF CALLING FOR GUSTAV TO TURN
WESTWARD JUST BEFORE REACHING THE NORTHERN GULF COAST.  THE NEW
OFFICIAL FORECAST TRACK REMAINS CONSISTENT WITH THE REMAINING
GUIDANCE IN TAKING GUSTAV INLAND IN LESS THAN 72 HOURS...AND IS
JUST EDGED EVER SO SLIGHTLY TO THE RIGHT...IN PART TO ACCOUNT FOR
THE RECENT RIGHT OF TRACK MOTION.  REGARDLESS OF THE DETAILS IN THE
TRACK...GUSTAV WILL LIKELY SLOW DOWN SIGNIFICANTLY IN THE
LONGER-TERM...WHICH COULD CAUSE A CONSIDERABLE FLOODING THREAT OVER
LOUISIANA AND TEXAS.


FORECAST POSITIONS AND MAX WINDS

INITIAL      30/1500Z 21.2N  82.1W   110 KT
 12HR VT     31/0000Z 22.5N  83.5W   105 KT...OVER WESTERN CUBA
 24HR VT     31/1200Z 24.3N  85.4W   115 KT
 36HR VT     01/0000Z 26.0N  87.3W   120 KT
 48HR VT     01/1200Z 27.8N  89.2W   110 KT
 72HR VT     02/1200Z 30.5N  92.5W    65 KT...INLAND
 96HR VT     03/1200Z 31.5N  94.0W    35 KT...INLAND
120HR VT     04/1200Z 32.0N  95.5W    30 KT...INLAND

$$
FORECASTER KNABB



This weather bulletin was brought to you by:
www.nashvilleweather.net