000 AGXX40 KNHC 101846 MIMATS MARINE WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 150 PM EST SAT DEC 10 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... 1037 MB HIGH PRES HAS BUILT OVER THE MID MISSISSIPPI VALLEY BEHIND THE FRONT PUSHING OFF SE U.S. COAST. THIS HAS INCREASED THE PRES GRADIENT BETWEEN THIS HIGH AND LOWER PRES TO THE S OVER THE NW CARIBBEAN. BUOY AND SHIP OBSERVATIONS SHOW FRESH TO STRONG NE TO E WINDS ACROSS MUCH OF THE NORTHERN HALF OF THE GULF. SEAS HAD ALREADY REACHED 10 FT AT BUOYS 42020 AND 42002 IN THE NW GULF AS OF 1700 UTC. THE HIGH WILL THEN WEAKEN SUN NIGHT THROUGH TUE ALLOWING FOR WINDS AND SEAS TO GRADUALLY DIMINISH AND SUBSIDE EARLY NEXT WEEK. SOUTHERLY RETURN FLOW WILL BECOME ESTABLISHED IN THE W GULF WED AS THE NEXT COLD FRONT MOVES INTO CENTRAL TEXAS. CARIBBEAN SEA AND TROPICAL N ATLC... THE SHEAR LINE OVER NW CARIBBEAN S OF 20N TO HONDURAS IS BEGINNING TO WEAKEN...WITH BUOY 42056 W OF THE SHEAR LINE SHOWING N-NE WINDS DIMINISHING FROM 19 KT AT 1300 UTC TO 14 KT AT 1700 UTC. THIS SHEAR LINE IS EXPECTED TO DISSIPATE LATER TODAY...BUT NW WINDS BEHIND THE BROAD SURFACE TROUGHING ALONG 80W WILL CONTINUE IN THE GULF OF HONDURAS AND MIGRATE TO ALONG THE COASTS OF HONDURAS AND NICARAGUA THROUGH MON. ANOTHER SHEAR LINE...THIS ONE OVER ANTIGUA AND THE FAR NE CARIBBEAN...HAS 20-25 KT NE WINDS TO ITS N ACCORDING TO THE 1426 UTC ASCAT PASS. THESE WINDS SHOULD DIMINISH BY EVENING AS THE RIDGING BETWEEN THE AFOREMENTIONED BROAD TROUGHING ALONG 80W AND ANOTHER TROUGH ALONG 50W IS WEAKENED AS THE EASTERN TROUGH APPROACHES. WEAKENING OF THIS RIDGING WILL ALSO DIMINISH THE FRESH NE WINDS NOTED S OF HISPANIOLA AND ALONG THE COAST OF COLOMBIA THIS MORNING. AFTER THE WEEKEND...THE PRES GRADIENT WILL THEN TIGHTEN OVER THE NW CARIBBEAN EARLY NEXT WEEK AS HIGH PRES BUILDS OVER THE U.S. MID-ATLANTIC STATES...RESULTING IN FRESH NE WINDS WITH SEAS BUILDING TO 8 FT BY THE END OF THE FORECAST PERIOD. THE AFOREMENTIONED SHEAR LINE OVER THE NE CARIBBEAN IS DRAPED ACROSS THE CENTRAL TROPICAL N ATLC WATERS NEAR 16N55W TO ANTIGUA. 0426 UTC ASCAT PASS SHOWS WINDS TO 20 KT JUST N OF THE ISLANDS WHILE BUOYS 41043 REPORTED 14 KT NE WINDS AND 8 FT SEAS AND BUOY 41044 REPORTED 17 KT NE WINDS AT 1700 UTC. LOW-LEVEL MOISTURE CONTINUES TO FEED UP FROM THE DEEP TROPICS OVER THE E CARIBBEAN TO ACROSS THE LESSER ANTILLES RESULTING IN CONTINUED RAINFALL AND THE LINGERING CHANCES OF FLASH FLOODING AND MUDSLIDES...WITH THE SHEAR LINE HELPING TO ENHANCE THE CONVECTION OVER THE ISLANDS. THE SHEAR LINE WILL BECOME DIFFUSE LATER TODAY...DISSIPATING TONIGHT AS A TROUGH ENTERS THE REGION FROM THE E. THIS TROUGH WILL THEN LIFT NW OF THE AREA SUN NIGHT WITH THE HIGHEST ASSOCIATED WINDS EXPECTED TO REMAIN JUST OUTSIDE OF THE OFFSHORE WATERS. HOWEVER NORTHEASTERLY SWELL OF 8-10 FT WILL PERSIST OVER MUCH OF THE ZONE SUN THROUGH TUE AND BEGIN TO SUBSIDE WED. SOUTHWEST NORTH ATLC S OF 31N W OF 55W... A NEW COLD FRONT IS MOVING SE OFF OF THE GEORGIA/N FLORIDA COASTS. FRESH TO STRONG NE WINDS ARE FILLING IN BEHIND THIS FRONT WITH SEAS EXPECTED TO BUILD TO 13-14 FT OFF THE NE FLORIDA COAST AT THE TAIL END OF A HEALTHY NE FETCH ZONE BY SUN NIGHT. THE NEW FRONT WILL THEN STALL OUT E OF FLORIDA SUN AFTERNOON...WITH ANOTHER REINFORCING SURGE OF NE WINDS IMPACTING THE NW PORTION EARLY NEXT WEEK. MEANWHILE...THE AFOREMENTIONED TROUGH EXPECTED TO PASS E THROUGH THE TROPICAL N ATLC SUN WILL DRIFT INTO THE E PORTION OF THE AREA MON WITH SEAS BUILDING TO 10 FT IN E-SE SWELL BEHIND IT. THIS TROUGH WILL MERGE WITH THE LATEST REINFORCING FRONT LATE MON...AND THE FEATURES WILL FINALLY SHIFT E OF THE AREA BY LATE TUE AS HIGH PRES BUILDS IN FROM THE NW. THE HIGH WILL SHIFT TO THE SE AND WILL BECOME ALIGNED ALONG 31N BY LATE WED ALLOWING FOR WINDS AND SEAS TO RELAX N OF 27N. 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 SCHAUER