000
AGXX40 KNHC 160800
MIMATS

MARINE WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
400 AM EDT TUE APR 16 2013

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... DEEP LAYER RIDGING IS BUILDING ACROSS THE GULF 
OF MEXICO...FOLLOWING A SHORT WAVE TROUGH IN THE MID LEVELS OF 
THE ATMOSPHERE AND ATTENDANT SURFACE LOW THAT EXITED EAST OF THE 
AREA ON MON. A TIGHTENING GRADIENT BETWEEN HIGH PRES OVER THE 
EASTERN UNITED STATES AND QUASISTATIONARY LOW PRES OVER N 
CENTRAL TEXAS/SOUTH CENTRAL OKLAHOMA WILL MAINTAIN MODERATE TO 
FRESH SE FLOW WILL DOMINATE THE WESTERN GULF WATERS THROUGH 
MIDWEEK...WITH LIGHT TO MODERATE E FLOW ELSEWHERE. MEANWHILE 
TROUGHING OVER THE NORTHERN ROCKIES WILL SWING EASTWARD INTO THE 
PLAINS STATES THROUGH THE LATTER HALF OF THE WEEK. GLOBAL MODELS 
REMAIN IN CLOSE AGREEMENT SHOWING AN ASSOCIATED COLD FRONT 
MOVING OFF THE TEXAS COAST BY LATE THU. THE MAIN FORECAST ISSUE 
CONTINUES TO BE THE POTENTIAL FOR GALE FORCE WINDS BEHIND THE 
FRONT OVER THE FAR WESTERN GULF LATE THU THROUGH FRI. THE ECMWF 
IS COMING INTO BETTER AGREEMENT WITH THE GFS INDICATING 10M 
WINDS TO GALE FORCE OVER THE WATERS OFFSHORE OF THE MEXICAN 
COAST. GFS ENSEMBLE PROBABILITIES FOR GALES ARE STILL REACHING AS 
HIGH AS 40% OFF THE TAMAULIPAS AND VERACRUZ COAST. SREF OUTPUT 
INDICATES PROBABILITIES FOR GALES FROM TAMPICO TO VERACRUZ CITY 
AS HIGH AS 60% BY FRI AFTERNOON. LOOKING AHEAD...GLOBAL MODEL 
CONSENSUS SHOWS THE FRONT STALLING OVER THE FAR SE GULF BY LATE 
SAT WITH WINDS AND SEAS SUBSIDING OVER THE WESTERN GULF.

CARIBBEAN SEA AND TROPICAL N ATLC S OF 22N W OF 55W...       
HIGH PRES NE OF THE AREA IN THE CENTRAL ATLC IS MAINTAINING 
FRESH TO STRONG TRADES OVER THE S CENTRAL CARIBBEAN AND IN THE 
GULF OF HONDURAS. LITTLE CHANGE IS EXPECTED IN THE OVERALL 
PATTERN THROUGH THE WEEK...ALTHOUGH THE RIDGE MAY WEAKEN ENOUGH 
BY THE END OF THE WEEK TO ALLOW FOR WINDS TO DIMINISH TO FRESH 
IN THE CENTRAL CARIBBEAN. THE STRONGER WINDS IN THE GULF OF 
HONDURAS WILL BE MORE PREVALENT IN THE OVERNIGHT HOURS DUE TO 
DRAINAGE EFFECTS. OTHERWISE MAINLY MODERATE EASTERLY WINDS WILL 
PREVAIL ACROSS THE REMAINDER OF THE CARIBBEAN...LOCALLY FRESH IN 
THE TROPICAL N ATLC...THROUGH THE FORECAST PERIOD. NO MAJOR 
DIFFERENCE IN GLOBAL MODEL SOLUTIONS FOR THE BASIN ARE NOTED. 

SW N ATLC S OF 31N W OF 55W...                                   
A LOW PRES NEAR 32N76W WILL MOVE SE A STALLED FRONTAL BOUNDARY 
ALONG 30N...REACHING 28N68W BY EARLY TUE. THE FRONT WILL 
DISSIPATE OVER FORECAST WATERS THROUGH TUE AS THE LOW PRES 
SHIFTS E OF THE AREA. RIDGING EXTENDING FROM HIGH PRES IN THE 
CENTRAL ATLC WILL DOMINATE CONDITIONS ACROSS THE BASIN THROUGH 
THE WEEK WITH MAINLY MODERATE TO LOCALLY FRESH EASTERLY WINDS 
PREVAILING. SEAS WILL BE 4 TO 7 FT OUTSIDE THE BAHAMAS...AND 1 
TO 3 FT INSIDE THE BAHAMAS THROUGH THE FORECAST PERIOD. NO MAJOR 
DIFFERENCE IN GLOBAL MODEL SOLUTIONS FOR THE BASIN ARE NOTED.
                                 
WARNINGS...
GULF OF MEXICO...
.GALE CONDITIONS EXPECTED AMZ017-019 AND AMZ023 FRI.
CARIBBEAN SEA AND TROPICAL N ATLC...
.NONE.
SW N ATLC...
.NONE.

EFFECTIVE 9 APRIL 2013...TAFB GRIDDED MARINE FORECASTS FOR 10-M 
WINDS...10-M WIND GUSTS...SIGNIFICANT WAVE HEIGHTS AND HAZARDS 
FOR THE OFFSHORE AND HIGH SEAS DOMAIN ARE AVAILABLE IN THE 
NATIONAL DIGITAL FORECAST DATABASE (NDFD) ON AN EXPERIMENTAL 
BASIS AT: HTTP://PREVIEW.WEATHER.GOV/GRAPHICAL

ADDITIONAL INFORMATION IS AVAILABLE AT: 
WWW.NWS.NOAA.GOV/OM/NOTIFICATION/PNS13OFFSHORE_HIGHSEAS.HTM

NOTE...GRIDDED MARINE FORECASTS AT: 
WWW.NHC.NOAA.GOV/TAFB/GRIDDED_MARINE ARE NO LONGER AVAILABLE. 

$$
FORECASTER CHRISTENSEN