000 AGXX40 KNHC 160731 MIMATS MARINE WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 230 AM EDT SUN OCT 16 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. GULF OF MEXICO... A STATIONARY FRONT EXTENDS FROM SW FLORIDA NEAR NAPLES TO 25N90W TO 18N94W. A TIGHT PRES GRADIENT REMAINS ACROSS THE GULF EXCEPT FOR THE NW GULF...BETWEEN HIGH PRES OVER THE LOWER MISSISSIPPI VALLEY AND BROAD LOW PRES OVER THE GULF OF HONDURAS AND N CENTRAL AMERICA. A HIGH RESOLUTION ASCAT PASS FROM THIS MORNING SHOWED NE-E WINDS OF 20-30 KT WITH HIGHER GUSTS S OF THE FRONT WITH MAINLY 15-20 KT N OF THE FRONT IN THE NE AND N CENTRAL GULF. THE FRONT WILL LIFT N AS WARM FRONT WILL GRADUALLY DISSIPATING THROUGH MON NIGHT. WINDS WILL THEN DIMINISH LATE MON THROUGH EARLY TUE AS THE PRES GRADIENT WEAKENS AHEAD OF A COLD FRONT FORECAST TO APPROACH THE AREA. THIS COLD FRONT WILL RAPIDLY MOVE INTO THE NW GULF TUE MORNING FROM NEAR SE LOUISIANA TO THE TEXAS/MEXICO BORDER...AND REACH FROM FROM TAMPA BAY FLORIDA TO THE YUCATAN WED MORNING BEFORE IT EXITS THE GULF LATE WED. N WINDS OF 20-30 KT WILL FOLLOW IN BEHIND THE FRONT WITH THE HIGHEST OF THE WINDS EXPECTED IN THE WESTERN PORTION WITH POSSIBLE HIGHER GUSTS TO NEAR GALE FORCE IN THE SW GULF TUE THROUGH THU. LATEST GFS GUIDANCE STILL SUGGESTS GALE FORCE NW-N WINDS IN THE FAR SOUTHERN SECTION OF THE SW GULF...WHILE OTHER MODELS HOLD WINDS TO GENERALLY 20-30 KT. 34 KT WIND PROBABILITIES ARE NOT BEING SHOWN FOR THAT PART OF THE GULF...SO WILL TENTATIVELY WILL HOLD OFF ON GALE WARNINGS FOR NOW. IF OTHER FUTURE MODEL RUNS SHOW SIMILAR GALE FORCE WINDS...AND OR THE PROBABILITIES OF 34 KT WINDS DUE BECOME EVIDENT IN THAT PART OF THE GULF...THEN WILL INSERT A GALE WARNING HEADLINER. MAY HAVE TO DUE EVEN IF THE AIR MASS BEHIND THE FRONT APPEARS TO BE LIKE IT WILL BE COLDER. CARIBBEAN SEA AND TROPICAL N ATLC... THE MEAN CENTER OF BROAD LOW PRES OVER THE WESTERN CARIBBEAN IS IDENTIFIED TO BE JUST INLAND THE YUCATAN PENINSULA NEAR 19.5N 87.7W WITH A PRES OF 1004 MB. THE 0236 UTC ASCAT PASS SHOWED A LARGE SWATH OF E-SE WINDS OF 20-30 KT N OF 18N AND W OF 82.5W. LIGHTER SE-S WINDS OF MOSTLY 20 KT WERE S OF 18N AND W OF 82W. IN ADDITION TO WINDS...ANOTHER MAIN ISSUE WITH THIS AREA OF BROAD LOW PRES IS THE COPIOUS AMOUNTS OF MOISTURE EVIDENT OVER THE WESTERN CARIBBEAN AND OVER THE ISLANDS OF CUBA...JAMAICA AND WESTERN HAITI AS WELL AS THE YUCATAN PENINSULA...BELIZE... HONDURAS AND MOST OF NICARAGUA. THIS MOISTURE WILL CONTINUE TO RESULT IN MODERATE TO LOCALLY HEAVY RAINFALL OVER THOSE AREAS. THIS PERSISTENT RAINFALL MAY RESULT IN LOCALIZED FLASH FLOODING AND MUDSLIDES. THE BROAD AREA OF LOW PRES IS FORECAST TO SLOWLY SHIFT W-NW THROUGH EARLY NEXT WEEK AND WINDS WILL DIMINISH AS THAT OCCURS WITH A WEAK PRES PATTERN LEFT IN ITS WAKE. A STRONG COLD FRONT WILL QUICKLY SWEEP THROUGH THE YUCATAN CHANNEL AND INTO THE NW CARIBBEAN ON WED WITH 20-25 KT NORTHERLY WINDS BEHIND IT...WITH POSSIBLE GUSTS TO 30 KT IN AND NEAR THE YUCATAN CHANNEL. SEAS MAY BUILD UP TO 10 OR 11 FT THROUGH THE YUCATAN CHANNEL IN A N SWELL LATE WED INTO THU. OTHERWISE...A WEAK PRES PATTERN WILL REMAIN OVER THE REMAINDER OF THE CARIBBEAN AND TROPICAL N ATLC THROUGH THE FORECAST PERIOD. A WEAKENING TROPICAL WAVE HAS ENTERED THE SE TROPICAL N ATLC WATERS AND WILL DAMPEN THROUGH THE NEXT 36-48 HOURS. A STRONGER TROPICAL WAVE WILL APPROACH THE TROPICAL N ATLC LATE WED...ALSO DAMPENING OUT AS IT APPROACHES THE LESSER ANTILLES FOR THE END OF THE WEEK. SW N ATLC S OF 31N W OF 55W... THE 0600 UTC SURFACE ANALYSIS HAS A STATIONARY FRONT EXTENDING FROM 31N65W SW TO THE NW BAHAMAS AND TO OVER S FLORIDA WHERE IT TRANSITIONS TO MORE OF A WARM FRONT. THE STATIONARY FRONT PORTION E OF ABOUT 71W WILL DRIFT E THROUGH EARLY MON...WHILE THE PORTION W OF 71W BEGINS TO LIFT BACK N AS A WARM FRONT AND WEAKEN. LATEST SATELLITE IMAGERY ALONG WITH NWS DOPPLER RADARS REVEAL SCATTERED TO NUMEROUS SHOWERS AND TSTMS COVERING THE WATERS W OF 70W. THIS ACTIVITY WILL LINGER THROUGH THE MIDDLE OF THE UPCOMING WEEK AS HIGH PRES NEAR 31N SHIFTS E. NE-E WINDS WILL BE ON THE INCREASE FROM THE NORTHERN BAHAMAS W TO THE STRAITS OF FLORIDA THROUGH LATE SUN NIGHT WITH RANGES OF 20-30 KT AND HIGHER GUSTS. WINDS THEN DIMINISH MON AS THE HIGH PRES RIDGE NEAR 31N SHIFTS TO THE NE AND WEAKENS. S TO SW WINDS INCREASE OVER THE WATERS N OF 25N BEGINNING LATE TUE AND INTO WED...AHEAD OF THE GULF OF MEXICO THAT IS EXPECTED TO MOVE OFF THE NE FLORIDA COAST EARLY WED. FRESH TO STRONG W TO NW WINDS UP TO 25 KT WILL FOLLOW THE FRONT. THE FRONT WILL REACH FROM NEAR 31N75W TO S FLORIDA BY LATE WED...THEN BEGIN TO WEAKEN AS IT APPROACHES FROM NEAR 31N70W TO WESTERN CUBA BY LATE THU. NLY WINDS BEHIND THE FRONT WEAKEN THU...EXCEPT S OF ABOUT 26N W OF THE FRONT WHERE THEY SHOULD BE N-NE AT 20 KT. WARNINGS... GULF OF MEXICO... .NONE. CARIBBEAN SEA AND TROPICAL N ATLC... .NONE. SW N ATLC... .NONE. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ FORECASTER AGUIRRE