000 AGXX40 KNHC 171929 MIMATS MARINE WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 330 PM EDT WED APR 17 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... A FAIRLY SHARP SHORT WAVE TROUGH OVER THE CENTRAL GULF OF MEXICO IS LIFTING ENE THIS AFTERNOON. INCREASED STABILITY BEHIND THE TROUGH AXIS IS ALLOWING FOG AND LOW STRATUS TO PERSIST ALONG THE TEXAS COAST DESPITE THE MIXING OF MODERATE TO FRESH BREEZES TO THE SURFACE. WINDS WILL REMAIN FRESH TONIGHT AND THU AS A STRONGER TROUGH CURRENTLY OVER THE WESTERN CONUS SWEEPS EWD OUT OVER THE SOUTHERN PLAINS WITH QUASI-STATIONARY LOW PRES CENTERED OVER THE REGION ENHANCING THE PRESSURE GRADIENT BETWEEN THE LOW AND HIGH PRES OVER THE WRN ATLC. GLOBAL MODELS REMAIN IN GOOD AGREEMENT WITH THE ECMWF/UKMET MODELS SLIGHTLY FASTER IN SHOWING AN ASSOCIATED COLD FRONT MOVING OFF THE TEXAS COAST BY THU EVENING. THE MAIN FORECAST ISSUE REMAINS THE POTENTIAL FOR GALE FORCE WINDS BEHIND THE FRONT OVER THE FAR WESTERN GULF THU NIGHT AND FRI. WINDS BEHIND THE FRONT WILL INCREASE TO NEAR GALE FORCE OFF THE TEXAS COAST...WITH THE POTENTIAL FOR FREQUENT GUSTS TO GALE FORCE FARTHER OUT OVER WARMER WATERS. GFS ENSEMBLE PROBABILITIES REMAIN UNCHANGED FOR GALES...70%...OVER GMZ111 THU NIGHT...AND 80% OVER GMZ117 AND GMZ123...SOUTHERN VERACRUZ ON FRI. DETERMINISTIC OUTPUT FROM GLOBAL MODELS SHOW 30-35 KT BEHIND FRONT... SLIGHTLY LOWER THAN EARLIER INDICATED. WILL INCLUDE THESE VALUES IN FORECAST AND GRIDS AND INCLUDED HEADLINE FOR GALES FRI. LOOKING AHEAD ...GLOBAL MODEL CONSENSUS SHOWS THE FRONT STALLING OVER THE SE GULF BY LATE SAT WITH WINDS AND SEAS SUBSIDING OVER THE WESTERN GULF. FRONT DISSIPATES SUN WITH LIGHT TO MODERATE E TO SE FLOW WILL COVERING THE GULF SUN AND MON. CARIBBEAN SEA AND TROPICAL N ATLC S OF 22N W OF 55W... WEAKER HIGH PRES ACROSS CENTRAL ATLC IS MAINTAINING FRESH TRADES OVER THE S CENTRAL CARIBBEAN AND IN THE GULF OF HONDURAS WITH MAINLY MODERATE EASTERLY WINDS PREVAILING ACROSS THE REMAINDER OF THE CARIBBEAN. STRENGTHENING HIGH PRES ACROSS THE NW ATLC WILL BUILD S INTO THE REGION LATE THU THROUGH THE WEEKEND TO STRENGTHEN FLOW AREA WIDE. WINDS AND SEAS SLOWLY SUBSIDE MON. OBSERVATIONS FROM LA CEIBA HONDURAS INDICATE SMOKE FROM FOREST FIRES CONTINUES TO BE AN ISSUE...AND GUIDANCE FROM SATELLITE ANALYSIS INDICATES LIMITATIONS TO VISIBILITY DUE TO SMOKE CONTINUES TO AFFECT THE GULF OF HONDURAS. SW N ATLC S OF 31N W OF 55W... A PAIR OF WEAK 1019 MB LOW PRES CENTERS ARE ANALYZED NEAR 30N70W AND 29N76W RESPECTIVELY...ALONG A MEANDERING AND DISSIPATING FRONTAL TROUGH. THE LOW PRES AREAS WILL DISSIPATE TONIGHT OR EARLY THU AS RIDGING EXTENDING FROM HIGH PRES IN THE CENTRAL ATLC DOMINATES CONDITIONS ACROSS THE BASIN. MODERATE TO LOCALLY FRESH EASTERLY WINDS SHOULD PREVAIL WITH SEAS 5 TO 7...LOCALLY 8 FT OUTSIDE THE BAHAMAS... AND 1 TO 3 FT INSIDE THE BAHAMAS THROUGH THE FORECAST PERIOD. STRONG HIGH PRES ACROSS THE NW ATLC WILL BUILD S ACROSS THE AREA THU NIGHT THROUGH THE WEEKEND TO STRENGTHEN FLOW AREA WIDE AND PRODUCE FRESH TO STRONG E TO SE TRADES S OF 26N WITH SEAS BUILDING TO 9 FT. WINDS AND SEAS SUBSIDE SLOWLY ON MON. WARNINGS... GULF OF MEXICO... .GALE CONDITIONS EXPECTED GMZ011...GMZ017...GMZ023 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 COBB