000 AGXX40 KNHC 211945 MIMATS MARINE WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 240 PM EST SUN NOV 21 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... HIGH PRES CENTERED OFF THE U.S. S CAROLINA COAST EXTENDS A RIDGE W AND SW TO FAR WESTERN PORTION OF THE SW GULF. WATER VAPOR IMAGERY IS SHOWING BROAD HIGH PRES COVERING MUCH OF THE CENTRAL AND WESTERN PORTIONS THIS AFTERNOON. BUOY OBSERVATIONS FROM DURING THE MORNING HOURS AND INTO EARLY THIS AFTERNOON SHOW E TO SE WINDS OF 15 KT ACROSS THE AREA TO THE E OF 93W WITH THE EXCEPTION OF THE SE PORTION WHERE BOTH HIGH RESOLUTION ASCAT AND A FEW SHIP OBSERVATIONS HAVE SHOWN AND ARE INDICATING PREDOMINATELY E WINDS OF 20 KT DUE TO A TIGHT PRES GRADIENT FOUND TO THE S OF THE RIDGE. OVER THE FAR WESTERN PORTION N OF 24N AND W OF 94W RETURN S WINDS FLOW IS OF 15 TO 20 KT. SEA STATE ANALYSIS FROM THIS MORNING AND EARLY AFTERNOON INDICATED SEAS IN THE 3 TO 5 FT OVER JUST ABOUT THE ENTIRE GULF...EXCEPT IN THE FAR NW PORTION NEAR THE TEXAS COAST WHERE A 7 FT MAXIMUM IS BEING REPORTED BY BUOY 42020 NEAR 27N97W...AND OVER THE FAR NORTHERN PORTION N OF 28N AND IN THE BAY OF CAMPECHE S OF 21N WHERE SEAS ARE LESS IN THE 2 TO 4 FT RANGE. AGAIN THE 1200 UTC RUN OF THE NOAA WAVEWATCH MODEL APPEARS REASONABLE WITH RESPECT TO THESE REPORTED VALUES SO WILL STAY CLOSE TO GUIDANCE OVERALL FOR THIS FORECAST. WILL STAY ABOUT 2 FT HIGHER COMPARED TO GUIDANCE FOR THE SE WATERS AND STRAITS OF FLORIDA THROUGH AT LEAST MON NIGHT BASED ON COUNTER FLOW AFFECTS WITH E SWELLS PROPAGATING IN FROM THE SW ATLC WATERS AND THROUGH THE STRAITS OF FLORIDA. AS FOR THE FORECAST...THE RIDGE WILL SHIFT EASTWARD AND WEAKEN THROUGH WED AS MODELS CONTINUE TO BE IN AGREEMENT WITH THIS SCENARIO. THIS WILL ALLOW FOR WINDS ACROSS THE AREA TO VEER AROUND TO THE SE TO S...HOWEVER WINDS OVER THE FAR WESTERN PORTION N OF 24N AND W OF 95W WILL REMAIN AT 15 TO 20 KT AS LOW PRES OVER THE GREAT PLAINS HELPS INCREASE TO THE ONSHORE FLOW. THESE WINDS THEN DECREASE SOME LATE TUE INTO WED AS A COLD FRONT ASSOCIATED WITH THE LOW PRES MOVES INTO FAR NW GULF LATE THU NIGHT...THEN REACHES FROM N CENTRAL FLORIDA TO 19N96W BY LATE FRI. MODELS ARE MORE IN CONSENSUS WITH TIMING OF FRONT INTO THE GULF AS COMPARED TO PREVIOUS RUNS. HIGH PRES WILL BUILD S ACROSS THE GULF IN THE WAKE OF THE FRONT WITH STRONG NORTHERLY WINDS SURGING S INTO THE WESTERN PORTION. THIS WILL MOST LIKELY LEAD TO GALE CONDITIONS FOR A PORTION OF THE FAR WESTERN SECTION OF THE SW GULF ON FRI...AND WILL HAVE TO CLOSELY CONSIDER PERHAPS ADDING GALE CONDITIONS TO THE SOUTHERN PORTION OF THE NW GULF BASED ON FUTURE MODEL TRENDS WITH RESPECT TO SURGE OF COLD POOL OF CANADIAN AIR MASS SOUTHWARD INTO THE GULF BEHIND THE FRONT. CARIBBEAN SEA AND TROPICAL N ATLC... A HIGH RESOLUTION ASCAT PASS FROM THIS MORNING SHOWED A RATHER STEADY SWATH OF NE 20 KT WINDS OVER MUCH OF THE CENTRAL AND EASTERN CARIBBEAN SEA AND THROUGH THE WINDWARD PASSAGE...WITH BUOY 42056 NEAR 20N85W INDICATING NE TO E WINDS OF 15 TO 20 KT. STRONG ATLC HIGH PRES WILL SHIFT SE AND WEAKEN THROUGH THU ALLOWING FOR TRADES TO DIMINISH SOME WED THROUGH FRI. SW N ATLC S OF 31N AND W OF 65W... A PARTIAL ASCAT PASS FROM THIS MORNING REVEALED A SWATH NE 20 TO 25 KT WINDS S OF ABOUT 27N WITH SEAS TO 10 FT AS REPORTED BY BUOY 41043 NEAR 21N65W. HESE WINDS ARE ALSO BEING CHANNELED TO THE S OF THE SE BAHAMAS AND SW THROUGH THE WINDWARD PASSAGE...AND ALSO TOWARDS THE COAST OF CUBA. HIGH PRES OF 1029 MB CENTERED NEAR 32N72W WILL DROP S INTO THE NORTHERN PORTION TUE...THEN WEAKEN AS IT MOVES SE THROUGH THU ALLOWING FOR WINDS TO DIMINISH OVER THE SOUTHERN PORTION OF THE AREA. THIS WILL ALSO ALLOW FOR SOUTHERLY WINDS TO INCREASE OVER THE NW WATERS BY LATE THU INTO FRI AHEAD OF A COLD FRONT THAT IS EXPECTED TO MOVE ACROSS THE SOUTHEAST U.S. AND BE PRECEDED BY INCREASING SW WINDS OVER THE FAR NORTHERN WATERS THU...WITH SPEEDS POSSIBLY REACHING 20 KT. WARNINGS... ATLC... .NONE. CARIBBEAN... .NONE. GULF OF MEXICO... .GMZ082...GALE CONDITIONS EXPECTED FRI S OF 25N W OF 95W... FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ FORECASTER AGUIRRE