000 AGXX40 KNHC 111820 MIMATS MARINE WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 230 PM EDT THU APR 11 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... W ATLC HIGH PRES RIDGE MAINTAINS STEADY SE TO S FRESH BREEZE ACROSS EASTERN HALF OF GULF WHILE STRONGER S RETURN FLOW EXTENDS ACROSS WESTERN PART OF BASIN AHEAD OF SHALLOW COLD FRONT WHICH CURRENTLY EXTENDS FROM 29N92W TO 23N98W. ABUNDANT TROPICAL MOISTURE BRINGS OVERCAST SKIES AND SCATTERED TSTMS ALONG AND WITHIN 60-90 NM OF FRONTAL BOUNDARY. NUMEROUS SHIP AND BUOY REPORTS INDICATE NEAR GALE WIND FORCE WITH SEAS 10-12 FT...2-3 FT ABOVE GFS GUIDANCE AND MORE IN TUNE WITH ECMWF. STRONG SE TO S FLOW AHEAD OF FRONT WITH SEAS 8-10 FT PRECEDE FRONT AND CURRENTLY EXTEND TO 88W. UPPER LEVEL SUPPORT SHIFT NE AWAY FROM GULF REGION WEAKENING FRONT...AND ITS WINDS...BY EARLY SAT. FRONT THEN STALLS ACROSS EASTERN PART OF GULF FROM SW FLORIDA TO YUCATAN PENINSULA LATE SAT OR SUN. STRENGTHENING W ATLC RIDGE MAY HOLD FRONT TILL IT DISSIPATES OR MAY PUSH IT N AS A WARM FRONT OVER EASTERN GULF. MODEL GUIDANCE LOWER WINDS BY EARLY SAT WITH LINGERING N SWELLS SUBSIDING BELOW 6 FT BY SUN. SW N ATLC S OF 31N W OF 55W... HIGH PRES CENTER 1024 MB OVER CENTRAL ATLC HAS BROAD RIDGE EXTEND E TO W RIDGE ACROSS ENTIRE SW N ATLC BASIN. WEAKENING GULF OF MEXICO COLD FRONT CROSSES N FLORIDA FRI NIGHT FORCING RIDGE E AND INCREASING SE-S RETURN FLOW TO A STRONG BREEZE ALONG E FLORIDA COAST N OF 29N. COLD FRONT LOSES ITS UPPER LEVEL SUPPORT BY THE TIME IT ENTERS BASIN AND ITS WINDS W OF BOUNDARY ARE NOT EXPECTED TO BE NOTHING ABOVE A FRESH BREEZE. SEAS SHOULD REMAIN AT 8 FT OR LESS. CARIBBEAN SEA AND TROPICAL N ATLC S OF 22N W OF 55W... PRES GRADIENT WEAKENS BRIEFLY ABOVE MENTIONED COLD FRONT PUSHES RIDGE EASTWARD...BUT THE CHANGE WINDS STRENGTH ACROSS THE CARIBBEAN CHANGES LITTLE. LOW PRES CENTER 1009 MB OVER NW COAST OF COLOMBIA SUFFICES TO MAINTAIN STRONG TO NEAR GALE FORCE WINDS ALONG ITS COAST. IF ANY SIGNIFICANT CHANGE HAPPENS...IT WOULD A DECREASE IN SE FLOW IN THE GULF OF HONDURAS WITH THE APPROACHING GULF OF MEXICO FRONT BECOMING DIFFUSE BY SAT. WARNINGS... GULF OF MEXICO... .NONE. 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 WALLY BARNES