000
AGXX40 KNHC 020701
MIMATS

MARINE WEATHER DISCUSSION 
NWS NATIONAL HURRICANE CENTER MIAMI FL
300 AM EDT MON MAY 2 2011

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

SW N ATLC AND TROPICAL ATLC...
THE TAIL OF A COLD FRONT CURRENTLY OVER EASTERN WATERS OF THE SW 
N ATLC WILL DISSIPATE TODAY. NORTHERLY SWELL ASSOCIATED WITH ITS 
ANCHOR LOW WILL MAKE ITS WAY SOUTHWARD THROUGH EASTERN WATERS OF 
THE SW N ATLC TODAY THROUGH WED AND DAMPEN AS IT MOVES THROUGH 
THE TROPICAL N ATLC WED THROUGH FRI. THE MWW3 WAS A FOOT OR TWO 
TOO HIGH WITH SIGNIFICANT WAVE HEIGHTS OVER THE ORIGIN REGION OF 
THIS NORTHERLY SWELL COMPARED TO ALTIMETER DATA. THE ECMWF WAVE 
MODEL WAS SLIGHTLY BETTER INITIALIZED AND WILL BE RELIED ON FOR 
THE SWELL FORECAST.

HIGH PRES BEHIND THAT FRONT WILL REMAIN ANCHORED N OF THE AREA 
UNTIL WED WHEN A NEW COLD FRONT MOVES OFF THE N FL COAST. THE 
00Z GFS IS THE FASTEST OF THE 00Z MODELS TO MOVE THE FRONT 
SOUTHEASTWARD INTO THE SW N ATLC ON WED. A SLIGHTLY SLOWER 
VERSION OF THE GFS...IN LINE WITH A 00Z GFS-ECMWF 
COMPROMISE...SEEMS BEST HERE. THE FRONT WILL MAKE ITS WAY INTO 
NE WATERS THU AND HIGH PRES WILL MOVE EASTWARD BEHIND IT ALONG 
30N ON FRI.


CARIBBEAN...
RAINFALL WILL BE THE MAIN WEATHER STORY OVER THE CARIBBEAN THIS 
FORECAST PERIOD. TROPICAL MOISTURE WITH PRECIPITABLE WATER 
VALUES AT OR ABOVE 50 MILLIMETERS ARE CURRENTLY FOUND OVER THE 
EASTERN CARIBBEAN BUT ARE EXPECTED TO STRETCH INTO THE SW 
CARIBBEAN OVER THE NEXT FEW DAYS AS THE MID-LEVEL REMNANTS OF 
THE COLD FRONT OVER THE SW N ATLC SWING S AND CONTAIN THE 
MOISTURE OVER THE CARIBBEAN. UPPER LEVEL DIFFLUENT FLOW 
ASSOCIATED WITH THE REAR RIGHT QUADRANT OF A LINGERING UPPER JET 
WILL ALLOW FOR VERTICAL LIFT OF THIS MOISTURE WHICH SHOULD 
ENHANCE PRECIPITATION OVER THE EASTERN CARIBBEAN EARLY TODAY AND 
SHIFTING INTO THE CENTRAL CARIBBEAN INCLUDING HISPANIOLA TONIGHT 
THROUGH WED. AN INCREASE IN PRECIPITATION IS ALSO EXPECTED IN 
THE SW CARIBBEAN PRIMARILY TUE THROUGH FRI.

THE 0150 UTC ASCAT PASS SHOWS 30 KT WINDS THROUGH THE WINDWARD 
PASSAGE. THE GFS AND UKMET SHOWS WINDS AS HIGH AS 25 KT HERE 
WHILE THE ECMWF AND NOGAPS ARE WEAKER STILL. A BEEFED UP VERSION 
OF THE GFS WILL BE USED HERE THROUGH MUCH OF THE PERIOD SINCE 
THE GENERAL PATTERN OVER THE AREA...WHICH SPORTS RIDGING TO THE 
N AND TROUGHING TO THE S...SHOULD CONTINUE.


GULF OF MEXICO...
THE COLD FRONT CURRENTLY OVER EASTERN TEXAS WILL BE SLOW TO MOVE 
OFFSHORE...WAITING UNTIL OVERNIGHT TONIGHT FOR THE UPPER LEVEL 
TROUGH TO CATCH UP TO THIS SURFACE BOUNDARY. ONCE IT DOES...THE 
MODELS HINT AT WINDS TO MINIMAL GALE FORCE ALONG THE MEXICAN 
COAST EARLY TUE MORNING. THE 18Z GEFS SHOWED UP TO AN 80 PERCENT 
CHANCE OF A GALE AT 1200 UTC TUE...BUT THAT CHANCE QUICKLY 
DROPPED OFF TO A ZERO PERCENT CHANCE BY 1800 UTC. THE 00Z GEFS 
HAS BACKED OFF ON THE ODDS OF A GALE. IT SHOWS ONLY A 10 PERCENT 
CHANCE AT 1200 UTC TUE. THE 00Z GFS STILL SHOWS GALE FORCE 
WINDS...BUT THE UKMET...NOGAPS...AND ECMWF DO NOT. SEA SURFACE 
TEMPERATURES IN THE NEAR SHORE WATERS OF THE WESTERN GULF ARE 
COOLER THAN THE SURROUNDING WATER. THIS IS AN INDICATION THAT 
THE STRONGEST WINDS MAY HAVE A HARDER TIME MIXING DOWN TO THE 
SURFACE. THEREFORE...WILL NOT ISSUE A GALE WARNING BEHIND THE 
FRONT.


WARNINGS..

ATLC...
.NONE.

CARIBBEAN...
.NONE.

GULF OF MEXICO...
.NONE.

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

$$
FORECASTER SCHAUER