000 AGXX40 KNHC 110604 MIMATS MARINE WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 200 AM EST SAT DEC 11 2010 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 RIDGE CURRENTLY EXTENDS FROM THE FLORIDA PANHANDLE SW ACROSS THE GULF TO THE BAY OF CAMPECHE. 15-20 KT SOUTHERLY RETURN FLOW REMAINS IN PLACE OVER THE NW GULF WITH MAINLY LIGHT WINDS OVER THE REMAINDER OF THE GULF. THESE CONDITIONS WILL PERSIST THROUGH THIS MORNING. SOUTHERLY RETURN FLOW WILL INCREASE AHEAD OF AN ARCTIC FRONT WHICH WILL PUSH SE OFF THE TEXAS COAST THIS EVENING. THE FRONT WILL REACH FROM SE LOUISIANA TO NEAR THE TEXAS/MEXICO BORDER TONIGHT THEN FROM APALACHEE BAY FLORIDA TO THE SW GULF SUN MORNING AND THEN FROM THE STRAITS OF FLORIDA TO THE YUCATAN CHANNEL SUN EVENING PUSHING SE OF THE WATERS THEREAFTER. STRONG NORTHERLY FLOW OF AT LEAST 30 KT WILL ARRIVE BEHIND THE FRONT WHICH WILL BUILD SEAS TO UP TO 17 FT SUN NIGHT. LATEST MODEL GUIDANCE IS NOW TRENDING STRONGER AND THERE IS STILL THE POSSIBILITY OF BRIEF GALE FORCE WINDS BEHIND THE FRONT MAINLY IN THE NE GULF. THE LATEST GFS ENSEMBLE 34 KT WIND PROBABILITIES HAVE INCREASED TO 40 PERCENT AT 00 UTC MON WHILE SREF 34 KT WIND PROBABILITIES ARE NOW UP TO 30 PERCENT. IF THIS TREND CONTINUES WILL NEED TO ISSUE A GALE WARNING FOR ABOUT A 6 HOUR TIME FRAME SUN EVENING/NIGHT. HIGH PRES BUILDS IN BEHIND THE FRONT WITH WINDS DIMINISHING FROM W TO E ACROSS THE GULF MON AND TUE. RIDGING RETURNS ACROSS THE GULF WATERS TUE AND WED WITH SOUTHERLY FLOW AGAIN BECOMING ESTABLISHED OVER THE W GULF WATERS AHEAD OF THE NEXT COLD FRONT WHICH WILL APPROACH THE NW GULF THU. CARIBBEAN AND TROPICAL N ATLC S OF 22N W OF 55W... 1008 MB LOW PRES REMAINS PARKED OVER EASTERN PANAMA NEAR 09N78W WITH A SHEAR AXIS EXTENDING N-NE FROM THE LOW TO 15N77W TO ACROSS HAITI. A RECENT 0228 UTC ASCAT PASS INDICATED 20 KT NORTHERLY WINDS W OF THE SHEAR AXIS...EXCEPT 10-15 KT IN THE FAR NW CARIBBEAN. RECENT SHIP OBSERVATIONS REPORT 25-30 KT WINDS ALONG THE COAST OF NICARAGUA AND N OF WESTERN PANAMA WITH SEAS TO 10 FT. SCATTERED SHOWERS CONTINUE TO OCCUR ALONG THE SHEAR AXIS WITH HEAVIER RAINFALL PERSISTING OVER EASTERN PANAMA AND NORTHERN COLOMBIA WITH THE THREAT OF FLASH FLOODING AND MUDSLIDES PERSISTING. THE LOW AND SHEAR AXIS WILL REMAIN NEARLY STATIONARY THROUGH SUN. MEANWHILE FRESH TRADES EXIST OVER THE REMAINDER OF THE CENTRAL AND E CARIBBEAN AND ALSO THE TROPICAL N ATLC WATERS. 9-11 FT NE SWELL EXISTS ACROSS THE TROPICAL N ATLC. A STRONG COLD FRONT WILL BLAST SE THROUGH THE YUCATAN CHANNEL SUN EVENING REACHING FROM EASTERN CUBA ACROSS JAMAICA TO CENTRAL PANAMA BY MON MORNING THEN FROM THE DOMINICAN REPUBLIC TO EASTERN PANAMA MON EVENING AND THEN FROM PUERTO RICO TO NW COLOMBIA TUE MORNING WHERE IT WILL STALL OUT AND WEAKEN THROUGH WED. NORTHERLY WINDS OF 20-30 KT BEHIND THE FRONT WILL BUILD SEAS TO UP TO 14 FT...HIGHEST ALONG THE COAST OF NICARAGUA. THE FRONT WILL SIGNIFICANTLY WEAKEN AS IT ENTERS THE NW PORTION OF THE TROPICAL N ATLC TUE NIGHT THROUGH WED ALTHOUGH SEAS WILL BUILD TO UP TO 13 FT IN NW SWELL BEHIND THE BOUNDARY. SW N ATLC S OF 31N W OF 55W... A COMPLEX WEATHER PATTERN REMAINS OVER THE REGION. 1013 MB LOW PRES IS POSITIONED NEAR 27N70W WITH A COASTAL TROUGH ARCHING FROM THE LOW CENTER THROUGH THE NORTHERN BAHAMAS TO 31N80W. A 0230 UTC ASCAT PASS CAPTURED NE TO E WINDS OF 20-30 KT N OF THIS BOUNDARY AND OBSERVATIONS AT NDBC BUOY 41047 NEAR 27N71W HAVE BEEN REPORTING 30 KT SUSTAINED WINDS FOR SEVERAL HOURS ALONG WITH 15 FT SEAS. MEANWHILE 10-15 KT WINDS EXIST S OF THE TROUGH. THE LOW IS EXPECTED TO DISSIPATE TODAY WHILE THE TROUGH REMAINS NEARLY STATIONARY BEFORE DISSIPATING TONIGHT. 1012 MB LOW PRES IS CENTERED NEAR 24N67W WITH A FRONTAL TROUGH EXTENDING FROM 31N53W TO 26N63W THROUGH THE LOW TO THE NORTHERN DOMINICAN REPUBLIC. A 0050 UTC ASCAT PASS SHOWED NE TO E WINDS OF 20-30 KT N OF THE TROUGH WITH 20-25 KT E-SE WINDS WITHIN 180 NM SE OF THE TROUGH. THE LOW WILL DISSIPATE TONIGHT WITH THE FRONTAL TROUGH MOVING NE OF THE AREA BY SUN MORNING. SW FLOW WILL RAPIDLY INCREASE OVER THE FAR NW WATERS LATE TONIGHT AHEAD OF AN ARCTIC COLD FRONT. MODEL GUIDANCE HAS TRENDED STRONG AHEAD OF THE FRONT WITH GFS ENSEMBLE 34 KT WIND PROBABILITIES NEAR 80 PERCENT ALONG 31N AND THUS A GALE WARNING IS NOW IN EFFECT N OF 28N WITHIN 150 NM SE OF THE FRONT BEGINNING AT 18 UTC SUN. THE MAIN FRONT WILL REACH FROM NEAR 31N78W TO SE FLORIDA SUN EVENING THEN FROM NEAR 31N74W TO EASTERN CUBA MON MORNING THEN FROM NEAR BERMUDA TO PUERTO RICO TUE MORNING PUSHING E OF THE AREA WED. MODEL GUIDANCE CONTINUES TO INDICATE 25-35 KT WINDS N OF 27N BEHIND THE FRONT BEGINNING SUN NIGHT (4TH PERIOD). SEAS WILL RAPIDLY BUILD TO UP TO 25 FT ALONG 31N MON NIGHT THROUGH TUE. WINDS WILL DIMINISH FROM W TO E TUE NIGHT THROUGH WED AS RIDGING BUILDS IN EXTENDING FROM HIGH PRES CENTERED OVER THE CAROLINAS SE ACROSS THE WATERS BY LATE WED. WARNINGS... ATLC... .AMZ080...GALE WARNING N OF 28N WITHIN 150 NM E OF FRONT SUN AFTERNOON THROUGH MON. .AMZ080...GALE WARNING N OF 27N W OF FRONT SUN NIGHT THROUGH TUE. CARIBBEAN... .NONE. GULF OF MEXICO... .NONE. 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