000
AGXX40 KNHC 270657
MIMATS

MARINE WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
200 AM EST MON DEC 27 2010

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

GULF OF MEXICO...
WINDS HAVE DIMINISHED BELOW 20 KT W OF 90W ACCORDING TO 
OBSERVATIONS THROUGH 06Z AND THE 0340 UTC ASCAT PASS. THE MWW3 
IS RUNNING AROUND 2 FT TOO HIGH WITH THE SUBSIDING SWELL IN THE 
SW AND CENTRAL GULF OF MEXICO COMPARED TO THE 06Z OBSERVATIONS. 
WINDS WILL CONTINUE TO DIMINISH THROUGH THE CENTRAL AND EASTERN 
GULF TODAY. RELIED PRIMARILY ON THE MWW3 FOR WAVE HEIGHT 
GUIDANCE BUT ATTEMPTED TO CORRECT FOR THE BIAS IN THE MWW3 TO 
HOLD ONTO HIGHER SEAS TOO LONG AFTER THE WINDS HAVE DIMINISHED. 
THE 00Z GFS AND 00Z ECMWF AGREE ON BRINGING THE SE RETURN FLOW 
IN THE NW GULF TO 20 KT OVERNIGHT MON NIGHT AND TO 25 KT 
OVERNIGHT TUE NIGHT CONTINUING THROUGH THU NIGHT. THERE IS 
BETTER AGREEMENT WITH THESE MODELS THAN THIS TIME YESTERDAY WHEN 
THE ECMWF WAS NOT CARRYING 25 KT WINDS IN THE NW GULF. THE TWO 
MODELS ARE IN BETTER AGREEMENT ALOFT WITH THE SOUTHERN STREAM 
TROUGH PASSING THROUGH MEXICO THROUGH WED AND THE SHORTWAVE 
ENERGY EXPECTED TO MOVE AHEAD OF THE TROUGH THROUGH THE GULF 
COAST STATES ON THE N SIDE OF THE RIDGE ON WED. THE 00Z ECMWF 
AND GFS ALSO AGREE WELL ON THE TIMING OF THE FRONT EXPECTED TO 
REACH THE TX COAST FRI NIGHT.

CARIBBEAN AND TROPICAL N ATLC...
SURFACE OBSERVATIONS AND THE 0156Z ASCAT PASS SHOW WINDS HAVE 
DIMINISHED BELOW 20 KT IN THE EASTERN CARIBBEAN TONIGHT WHILE 
STRONG NE WINDS HAVE MOVED INTO THE WESTERN AND S CENTRAL 
CARIBBEAN WITH THE COLD FRONT THAT CURRENTLY LIES FROM EASTERN 
CUBA TO COSTA RICA. THE 00Z ECMWF AND 00Z GFS CONTINUE TO BE IN 
GOOD AGREEMENT WITH THE TIMING OF THE FRONT. THE LEADING EDGE OF 
THE COLD FRONT TRAVELS THROUGH THE WINDWARD PASSAGE MON AND THE 
MONA AND ANEGADA PASSAGES TUE. WINDS WILL LIKELY BE INTENSIFIED 
AS THEY FUNNEL THROUGH THE PASSAGES...WITH THE GFS SHOWING WINDS 
TO JUST BELOW GALE FORCE IN THE MONA PASSAGE AND OFF THE SE 
COAST OF THE DOMINICAN REPUBLIC FROM TUE MORNING TO WED MORNING. 
THE 00Z ECMWF IS NOT AS STRONG...ONLY BRIEFLY SHOWING A SMALL 
AREA OF 30 KT WINDS HERE EARLY WED MORNING. GIVEN THIS IS A 
CLIMATOLOGICALY FAVORED LOCATION FOR WINDS TO BE ENHANCED...THE 
FORECAST HEDGES TOWARD THE STRONGER GFS HERE.

SW N ATLC...
THE 0200Z ASCAT PASS SHOWS GALE FORCE WINDS WITHIN THE GALE 
WARNING AREA WITHIN 210 NM AHEAD OF THE FRONT AS WELL AS BEHIND 
THE FRONT N OF 27N. A SECONDARY SURGE OF COLD DRY AIR IS MOVING 
IN BEHIND THE MAIN FRONT OVER N WATERS WITH A TROUGH FROM 31N75W 
TO 30N79W. THE MODELS CAUGHT ONTO THIS SECONDARY SURGE A FEW 
RUNS AGO...EXPANDING THE WIND FIELD W. THE FORECAST REFLECT 
THIS. THE GFS IS SLIGHTLY FASTER TO DIMINISH WINDS BELOW 20 KT 
OVER THE W PORTION THAN THE ECMWF. FOR NOW...WILL STICK WITH THE 
STRONGER ECMWF WHICH BEEN MORE CONSISTENT WITH THIS SECONDARY 
SURGE IN THE FORECAST PERIOD. 


WARNINGS..

ATLC...
.GALE WARNING N OF 26N...AMZ080.

CARIBBEAN...
.NONE.

GULF OF MEXICO...
.NONE.

FOR ADDITIONAL INFORMATION PLEASE VISIT 
HTTP://WWW.HURRICANES.GOV/MARINE

$$
FORECASTER SCHAUER