000
AGXX40 KNHC 061825
MIMATS

MARINE WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
130 PM EST TUE JAN 06 2009

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

GULF OF MEXICO AND ATLANTIC...
A LONGWAVE TROUGH OVER THE PLAINS WILL PASS E THROUGH THE GULF 
OF MEXICO ON THU AND INTO THE SW N ATLC BY FRI.  THE ASSOCIATED 
SURFACE COLD FRONT IS EXPECTED TO GENERATE WINDS TO GALE FORCE 
AHEAD OF IT OVER THE SW N ATLC ZONE N OF 29N ON WED/THU.  THE 
MODELS ARE IN REASONABLE AGREEMENT WITH THE STRENGTH AND TIMING 
OF THIS COLD FRONT...BUT APPEAR TO BE RUNNING SLIGHTLY WEAK WITH 
THE STRENGTH OF THE SOUTHERLY FLOW AHEAD OF THE COLD FRONT.  THE 
1238 UTC QUIKSCAT PASS SHOWS WINDS INTO THE 25 TO 30 KT RANGE 
HERE WHILE THE 35 KM RESOLUTION GFS DOES NOT GENERATE WIND THAT 
STRONG UNTIL 0000 UTC.  EVEN THE 20 KM NAM IS WEAKER THAN 
QUIKSCAT AND SEVERAL SURFACE OBSERVATIONS AHEAD OF THE FRONT ARE 
REPORTING.  THEREFORE...BUMPED THE WINDS UP SLIGHTLY AHEAD OF 
THE COLD FRONT INTO THE FORECAST PERIOD.  BELIEVE THE WINDS WILL 
GET TO GALE FORCE AS THE FRONT EMERGES OFF THE FL/GA COAST WED 
AFTERNOON THROUGH THU.

A SECOND COLD FRONT WILL PUSH SOUTHEASTWARD INTO THE NORTHERN 
GULF OF MEXICO OVER THE WEEKEND.  WITH THE STEERING FLOW 
BECOMING MORE ZONAL ACROSS THE CENTRAL AND EASTERN U.S. ON 
FRI/SAT...THE MODELS ARE HAVING A HARD TIME AGREEING ON THE 
STRENGTH AND TIMING OF THE COLD FRONT OVER THE GULF.  THE GFS 
AND NOGAPS SOLUTIONS ARE GENERALLY FASTER TO CARRY THE LEADING 
EDGE OF THE FRONT EASTWARD THROUGH THE GULF THAN THE UKMET AND 
ECMWF.  GIVEN THE TREND IN THE FORECAST FOR MORE ZONAL 
FLOW...THINK THE UKMET AND ECMWF MAY BE TOO SLOW.  DO NOT HAVE A 
GOOD REASON TO STRAY FROM THE GFS.

CARIBBEAN...
THE SOUTHERN END OF THE COLD FRONT CURRENTLY OVER THE GULF OF 
MEXICO IS EXPECTED TO PASS THROUGH THE YUCATAN CHANNEL TOMORROW 
AND DISSIPATE OVER THE NW CARIBBEAN THU.  WINDS OVER THE NW 
CARIBBEAN ARE ALREADY BEGINNING TO TURN MORE SOUTHERLY AHEAD OF 
THE COLD FRONT AND ARE EXPECTED TO TURN MORE N OF E AS THE FRONT 
PASSES THROUGH...BUT CONSIDERING THIS IS A RELATIVELY WEAK FRONT 
ONCE IT REACHES THE CARIBBEAN...WINDS ARE NOT EXPECTED TO EXCEED 
25 KT DUE TO THE FRONTAL PASSAGE.  WINDS OVER 25 KT ARE BEING 
REPORTED NEAR THE COAST OF COLOMBIA ACCORDING TO THE 1428 ASCAT 
PASS...AND WINDS ARE EXPECTED TO REMAIN ABOVE 25 KT HERE THROUGH 
THE PERIOD DUE TO THE PRESSURE GRADIENT BETWEEN LOW PRESSURE 
OVER SOUTH AMERICA AND MEAN HIGH PRESSURE N OF THE CARIBBEAN 
CENTERED NEAR 25N.


ATLANTIC...
NONE.

CARIBBEAN...
NONE.

GULF OF MEXICO...
NONE.

FORECASTER SCHAUER CLARK. TROPICAL PREDICTION CENTER.