000 AGXX40 KNHC 201924 MIMATS MARINE WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 224 PM EST WED JAN 20 2010 MARINE WEATHER DISCUSSION FOR GULF OF MEXICO...CARIBBEAN SEA AND SOUTHWEST NORTH ATLC S OF 31N W OF 55W GULF OF MEXICO... A TIGHT PRES GRADIENT BETWEEN HIGH PRES ALONG THE FLORIDA ATLC COAST AND A LOW PRES SYSTEM IN THE GREAT PLAINS HAS ALLOWED FOR SOUTHERLY RETURN FLOW TO INCREASE IN THE GULF. A 1523 UTC ASCAT PASS CAPTURED 15-20 KT WINDS OVER THE GULF. A FRONTAL TROUGH WILL MOVE OFF THE TEXAS COAST TONIGHT WITH 20-25 KT WINDS EXPECTED N OF 27N AHEAD OF THE TROUGH. MODELS HAVE COME INTO BETTER AGREEMENT WITH REGARD TO THE TRACK OF THE LOW WHICH WILL MOVE FROM THE GREAT PLAINS TO THE APPALACHIANS WHILE A SECOND LOW DEVELOPS TO THE E-SE ALONG THE COASTAL CAROLINAS AND MOVES UP THE MID-ATLANTIC COAST. THE FRONTAL TROUGH WILL WEAKEN AND DISSIPATE FRI THROUGH FRI NIGHT OVER THE E GULF. WITH HIGH PRES BRIEFLY RETURNING BEHIND THE SYSTEM. SOUTHERLY RETURN FLOW INCREASES ONCE AGAIN OVER THE W GULF FRI NIGHT WITH ANOTHER FRONTAL TROUGH MOVING OFFSHORE OF TEXAS ON SAT. A COLD FRONT WILL QUICKLY FOLLOW THE FRONTAL TROUGH WITH THE TWO FEATURES MERGING ON SUN OVER THE W GULF. THE COLD FRONT WILL STRETCH FROM SE LOUISIANA TO THE BAY OF CAMPECHE BY SUN AFTERNOON AND WITH ADEQUATE COLD AIR ADVECTION BEHIND THE FRONT NORTHERLY WINDS OF 20-25 KT ARE EXPECTED W OF THE FRONT WITH 20-25 KT SOUTHERLY WINDS E OF THE FRONT. THE FRONT WILL WEAKEN ON MON WITH THE AIRMASS QUICKLY MODIFYING OVER THE GULF WATERS ALLOWING FOR WINDS TO DIMINISH. HIGH PRES BUILDS IN ACROSS THE GULF BEHIND THE FRONT BY LATE MON. CARIBBEAN AND TROPICAL N ATLC W OF 55W... A TIGHT PRES GRADIENT REMAINS OVER THE CARIBBEAN WITH MODERATE TO STRONG BREEZE EASTERLY TRADES ACROSS THE CENTRAL AND E CARIBBEAN. THE STRONGEST WINDS REMAIN NEAR THE COAST OF COLOMBIA WHERE A GALE WARNING REMAINS IN EFFECT THROUGH THE NEXT 48 HOURS. A 1052 UTC WINDSAT SCATTEROMETER PASS CAPTURED GALE FORCE WINDS RIGHT OVER THE WARNING AREA. MEANWHILE SOUTHERLY RETURN FLOW IS SETTING UP OVER THE NW CARIBBEAN WITH THE STRONGEST WINDS EXPECTED TO OCCUR TONIGHT IN THE GULF OF HONDURAS AS WINDS BECOME FUNNELED UP ALONG THE YUCATAN PENINSULA. THIS PATTERN PERSISTS THROUGH THU AND THU NIGHT WITH THE SOUTHERLY FLOW AND THE TRADES WEAKENING FRI AND SAT AS A COLD FRONT MOVES BY TO THE N IN THE SW N ATLC WATERS WHICH WILL SIGNIFICANTLY WEAKEN THE PRES GRADIENT. SOUTHERLY RETURN FLOW WILL INCREASE AGAIN IN THE NW CARIBBEAN SAT NIGHT THROUGH SUN NIGHT AHEAD OF A DEEP COLD FRONT THAT WILL MOVE THROUGH THE GULF OF MEXICO WATERS WHICH WILL EVENTUALLY STALL OUT IN THE FAR NW CARIBBEAN JUST S OF THE YUCATAN CHANNEL BY MON NIGHT. SW N ATLC S OF 31N W OF 55W... 1018 MB HIGH PRES NEAR 28N76W IS THE DOMINATE WEATHER FEATURE OVER THE AREA TODAY. A 1340 UTC AND A SUBSEQUENT 1521 UTC ASCAT PASS CAPTURED VERY TRANQUIL WINDS (VARIABLE 5-10 KT) ACROSS THE MAJORITY OF THE BASIN. MEANWHILE A STATIONARY FRONT EXTENDS FROM NEAR 22N65W TO THE NORTH COAST OF THE DOMINICAN REPUBLIC WITH SCATTERED SHOWERS OCCURRING AHEAD OF THE FRONT. HIGH PRES WILL SHIFT E OF 65W EARLY THU WHICH WILL ALLOW FOR SOUTHERLY RETURN FLOW TO BECOME ESTABLISHED AND STRENGTHEN NEAR THE FLORIDA COAST THROUGH THE DAY THU. A COLD FRONT WILL THEN MOVE FROM THE SOUTHEAST U.S. STATES ACROSS THE N PORTION OF THE WATERS THU NIGHT. GALE FORCE WINDS CONTINUE TO BE FCST N OF 27N AND AHEAD OF THE FRONT BEGINNING FRI EVENING THROUGH SAT AFTERNOON. A SET OF LARGE NW-N SWELL MOVES IN BEHIND THE FRONT WITH COMBINED SEAS PEAKING AROUND 17 FT BY LATE FRI NIGHT ALONG 65W. THE FRONT WILL REACH FROM 31N74W TO NEAR CAPE CANAVERAL FLORIDA BY EARLY FRI THEN FROM 31N65W TO THE CENTRAL BAHAMAS BY FRI EVENING AND THEN FINALLY MOVING SE OF 65W BY SAT NIGHT. HIGH PRES BRIEFLY BUILDS BACK IN BEHIND THE FRONT WITH SOUTHERLY RETURN FLOW EXPECTED BY SUN AFTERNOON AHEAD OF THE NEXT COLD FRONT WHICH WILL MOVE OFF THE N FLORIDA COAST EARLY MON. SOUTHERLY WINDS AHEAD OF THIS NEXT FRONT ARE CURRENTLY PROGGED TO REMAIN LESS THAN GALE FORCE. WARNINGS... ATLC... .GALE CONDITIONS EXPECTED N OF 27N E OF FRONT FRI AND FRI NIGHT...AMZ080. CARIBBEAN... .GALE WARNING FROM 11N TO 15N BETWEEN 72W AND 77W...AMZ084 AND AMZ086. GULF OF MEXICO... .NONE. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ FORECASTER LEWITSKY