000 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