000
AGXX40 KNHC 121820
MIMATS

MARINE WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 
120 PM EST TUE DEC 12 2006

MARINE WEATHER DISCUSSION FOR GULF OF MEXICO...CARIBBEAN SEA AND 
SOUTHWEST NORTH ATLC S OF 31N W OF 55W.

GULF OF MEXICO...
WEAK COLD FRONT MOVED OFF THE TEXAS COAST THIS MORNING AND 
EXTENDS ROUGHLY FROM LAKE CHARLES LA SW INTO NE MEXICO...BUT THE 
SFC FLOW IS ALREADY TURNING NLY OVER THE SW GULF WATERS AND HAS 
MADE THE BOUNDARY DIFFICULT TO DISTINGUISH. ELY WINDS ARE SLOWLY 
DIMINISHING OVER THE E GULF WATERS WITH THE FRONT APPROACHING 
FROM THE W...BUT ARE STILL HOVERING AT OR JUST ABOVE 20 KT E OF 
88W. WAVEWATCH GUIDANCE HAS ACTUALLY BEEN A BIT UNDERDONE OVER 
THE E GULF...WHERE IT IS SHOWING 5-6 FT WHERE BUOY 42003 HAS 
BEEN REPORTING 8-9 FT. THE FRONT IS EXPECTED TO STALL AND BECOME 
RATHER DIFFUSE FROM THE FLORIDA PANHANDLE TO THE W GULF WED AND 
THU. THEREAFTER THE FORECAST ALL HINGES ON POSSIBLE LOW 
DEVELOPMENT OVER THE S/CENTRAL GULF. FOR THE PAST DAY OR 
SO...THE GFS HAS BEEN THE MAIN OUTLIER AS FAR AS RAPID SPIN-UP 
OF A LOW OVER THE E GULF AND A SUBSEQUENT TREK ACROSS FLORIDA. 
HOWEVER...THE SHORTWAVE TROUGH WHICH WILL ULTIMATELY BECOME THE 
DETERMINING INGREDIENT IS JUST NOW MOVING ONSHORE THE W COAST OF 
THE UNITED STATES AND IS NOW BEING DETECTED BY THE RADIOSONDE 
NETWORK. AS IF ON CUE...THE 12Z GFS RUN HAS COME IN MUCH MORE 
SUBDUED MATCHING THE OTHER GLOBAL MODELS AND SHOWS THE 
STALLED/DIFFUSE FRONT WITHOUT A LOW MOVING ACROSS FRI/SAT 
(ALTHOUGH IT STILL DEVELOPS A GALE-FORCE LOW OVER THE W ATLC). 
WITH THIS WEAKER SOLUTION...WINDS ARE UNLIKELY TO RISE ANY 
HIGHER THAN 15 KT AND THIS ESSENTIALLY KEEPS THE FORECAST 
LARGELY CONSISTENT FROM PREVIOUS PACKAGES. HIGH PRES TAKES 
CONTROL OVER THE GULF BEHIND THE FRONT FRI INTO SUN WITH ONLY 
PERHAPS SOME INCREASED RETURN FLOW OFF THE TEXAS COAST (AHEAD OF 
THE NEXT STORM SYSTEM).

SW N ATLC...
WINDS OVER THE CENTRAL PART OF THE ZONE ARE TRENDING DOWN IN THE 
20-25 KT RANGE...AND THIS SHOULD CONTINUE INTO LATE WED AS THE 
HIGH OFF THE CAROLINAS SHIFT E. A WEAK COLD FRONT MOVES OFF THE 
GEORGIA/N FLORIDA COAST LATE WED BUT QUICKLY STALLS JUST 
OFFSHORE THROUGH FRI. AS INDICATED ABOVE...THE 12Z GFS RUN IS 
SHOWING A LESS AGGRESSIVE LOW DEVELOPMENT SCENARIO OVER THE GULF 
OF MEXICO ALTHOUGH IT STILL SHOWS SPIN-UP OVER THE W ATLC LATE 
FRI THROUGH SUN. SINCE THE GFS FINALLY CAME IN LINE WITH THE 
OTHER MODELS FOR THE GULF (AND WHAT THE ENSEMBLE HAS BEEN 
INDICATING FOR SEVERAL DAYS)...IT SEEMS PRUDENT TO CONTINUE TO 
FOLLOW THE ENSEMBLE MEAN FOR NOW. BASED ON THIS...THE STALLED 
FRONT WILL BEGIN TO MOVE E LATE FRI AND EXTEND FROM NEAR BERMUDA 
TO THE W BAHAMAS SAT THEN MOVE E OF THE AREA SUN. WINDS COULD 
INCREASE BEHIND THE FRONT ON SUN...BUT NOT AS STRONG AS 
INDICATED BY THE GFS.

CARIBBEAN AND TROPICAL ATLC...
WINDS OVER THE NW CARIBBEAN ARE SLOWLY DIMINISHING AS THE W ATLC 
HIGH PRES AREA MOVES E. WINDS OVER THE CENTRAL CARIBBEAN REMAIN 
ON THE STRONG SIDE DUE TO THE HIGH AS BUOY 42058 CONTINUES TO 
SHOW 1-MIN WINDS OF 27 KT. NO MAJOR CHANGES ARE EXPECTED OVER 
THE CARIBBEAN WATERS THROUGH SUN WITH THE PRES GRADIENT EXPECTED 
TO REMAIN CONSTANT. E OF THE ISLANDS...WINDS ARE GENERALLY ABOUT 
15 KT WITH 6-8 FT SEAS IN NE SWELLS. HIGH PRES SLIDES E OVER THE 
CNTRL ATLC BEGINNING WED AND INCREASES WINDS OVER THE N PART OF 
THE ZONE WED THROUGH FRI WITH A BUILDING NE SWELL. WINDS AND 
SEAS DIMINISH AGAIN SAT AND SUN AS THE HIGH WEAKENS AND A FRONT 
MOVES ACROSS THE W ATLC.
  
WARNINGS...

ATLANTIC...
NONE.

CARIBBEAN...
NONE.

GULF OF MEXICO...
NONE.

FORECASTER BERG