000 AGXX40 KNHC 290702 MIMATS MARINE WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 200 AM EST SAT JAN 29 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... 1021 MB HIGH PRES OVER THE W CENTRAL GULF WILL SHIFT INTO THE FAR EASTERN GULF BY EARLY SUN. SOUTHERLY RETURN FLOW WILL INCREASE TO 15 TO 20 KT OVER MUCH OF THE FAR WESTERN GULF SAT...SPREAD OVER THE WESTERN HALF OF THE GULF SAT NIGHT...THEN DIMINISH SUN. GLOBAL MODELS INDICATE A BROAD UPPER TROUGH WILL BECOME ESTABLISHED FROM THE NORTHERN PLAINS TO THE SOUTHERN ROCKIES SUN INTO MON. A VIGOROUS SHORT WAVE TROUGH WILL PIVOT AROUND THE BASE OF THE LONG WAVE TROUGH FROM THE SOUTHERN ROCKIES INTO THE MID MISSISSIPPI VALLEY MON AND TUE...AIDING FORMATION OF A SURFACE LOW OVER TEXAS. OVER THE GULF...LIGHT TO MODERATE SE FLOW WILL PERSIST SUN INTO MON...THEN START TO INCREASE LATE MON AS THE LOW PRES FORMS OVER TEXAS. THE GFS POSITION IS A LITTLE FURTHER SOUTH THAN THE ECMWF...AND THUS SHOWS A GREATER EXTENT OF 20 TO 25 KT SOUTHERLY WINDS ON TUE. BOTH MODELS SHOW AN ASSOCIATED STRONG COLD FRONT PLUNGING INTO THE NW GULF LATE TUE...FOLLOWED BY STRONG NORTHERLY WINDS. THE MAIN FORECAST ISSUE FOR WED IS WHETHER OR NOT THERE WILL BE WINDS TO GALE FORCE OVER THE WESTERN GULF BEHIND THE FRONT. THE MAIN LONG WAVE TROUGH REMAINS TO THE WEST...WITH SW FLOW ALOFT LIMITING STRONG COLD AIR ADVECTION. AS A RESULT...LATEST GFS ENSEMBLES DO NOT INDICATE A STRONG CHANCE OF GALES AT THIS TIME...LESS THAN 10 PERCENT. LOOKING AHEAD BEYOND THE FORECAST PERIOD...THE GFS AND ECMWF SHOW A REINFORCING SURGE INTO THU AS HIGH PRES BUILDS OVER TEXAS...AND THE GFS SHOWS WINDS REACHING GALE FORCE OVER THE WESTERN GULF THU...WITH THE ECMWF SLIGHTLY WEAKER. CARIBBEAN AND TROPICAL N ATLC W OF 55W... TRANQUIL CONDITIONS PREVAIL ACROSS THE GULF THIS AFTERNOON AND ARE EXPECTED TO PERSIST OVER THE BASIN THROUGH EARLY SUNDAY AS A 1025 MB SURFACE HIGH CENTERED OFF THE COAST OF S TEXAS MIGRATES EAST ACROSS THE GULF. A REINFORCING SURGE OF COOL AIR ASSOCIATED WITH THE UPPER TROUGH SWINGING ACROSS THE ERN U.S. HAS MOVED ACROSS NE PORTIONS OF THE GULF OVERNIGHT AND THIS MORNING BRINGING COOL AND VERY DRY AIR AND W-NW WINDS NEAR 15 KT FROM SE LOUISIANA TO THE W CENTRAL COAST OF FLORIDA...WITH SEAS TO 4 FT. AS THE HIGH MOVES INTO THE CENTRAL GULF SAT MORNING MODERATE RETURN FLOW WILL SET UP ACROSS THE FAR WRN GULF AND THEN EXPAND ACROSS MOST OF THE W HALF TO MODERATE TO FRESH RETURN FLOW BY SAT NIGHT AS THE HIGH MOVES TO NEAR THE W CENTRAL FLORIDA COAST. GLOBAL MODELS SHOW THE VORT CENTER OFF THE BAJA CALIFORNIA COAST MOVING E-NE ACROSS FROM NW MEXICO AND TEXAS AND TO COAST OF THE CAROLINAS THROUGH SUN NIGHT...ALLOWING A SFC LOW CENTER TO DEVELOP ACROSS TEXAS AND AN ASSOCIATED WEAK COLD FRONT TO MOVE INTO EAST TEXAS. THE LOW DISSIPATES WHILE THE FRONT STALLS OVER E TEXAS THEN DRIFTS BACK TO THE NW IN ADVANCE OF A MORE SIGNIFICANT S/W MOVING ACROSS THE ROCKIES AND INTO N TEXAS TUE AFTERNOON. GLOBAL MODELS HAVE FINALLY COME INTO BETTER AGREEMENT ON THE EVOLUTION OF AN ASSOCIATED SURFACE LOW AND COLD FRONT AFTER SIGNIFICANT SPREAD THE PAST SEVERAL DAYS. A SURFACE LOW IS EXPECTED TO DEVELOP ALONG THE OLD LINGERING BOUNDARY ACROSS CENTRAL TEXAS AND THEN DEEPEN AS IT MOVES NE TO THE TN VALLEY TUE NIGHT. FRESH SE TO S RETURN FLOW WILL ENVELOPE MOST OF THE GULF AHEAD OF THIS NEW COLD FRONT TUE...WITH SEAS BUILDING 6 TO 8 FT ACROSS W AND NW PORTIONS. COLD FONT IS EXPECTED TO MOVE OFF THE TEXAS COAST BY 00Z WED AND MOVE SE...REACHING FROM NEAR APALACHICOLA TO WRN BAY OF CAMPECHE BY 00Z THU...WITH STRONG NLY FLOW 25 TO 30 KT AND POSSIBILITY OF GALES ALONG THE GULF COASTS OF S TEXAS AND MEXICO. GFS MAINTAINS SUFFICIENT RIDGING SE OF FRONT TO BLOCK IT FRONT MOVING INTO SE GULF LATE THU WHILE EUROPEAN MODELS BOTH BLAST FRONT ALL THE WAY THROUGH THE GULF BY 00Z FRI. AT THIS TIME I WOULD FAVOR THE EUROPEAN CONSENSUS. CARIBBEAN AND TROPICAL N ATLC W OF 55W... AN ASCAT PASS FROM 02Z SHOWED A WEAK TROUGH S OF JAMAICA...POSSIBLY THE SOUTHERN REMNANT OF AN EARLIER COLD FRONT THAT MOVED INTO THE AREA A COUPLE OF DAYS AGO. THE ASCAT AND AN SHIP OBSERVATION BOTH SHOWED 20 KT N TO NE WINDS W OF THE TROUGH TO SWAN ISLAND. A SECOND FRONT HAD PUSHED INTO THE YUCATAN CHANNEL LAST EVENING...BUT APPEARS TO HAVE DISSIPATED ALREADY. WINDS WILL DIMINISH OVER THE FAR NW CARIBBEAN THIS MORNING...BUT AREAS OF HIGH PRES MIGRATING EASTWARD TO THE NORTH OF THE BASIN WILL MAINTAIN FRESH TRADE WINDS FROM THE TROPICAL N ATLC THROUGH THE CENTRAL CARIBBEAN THROUGH THE MIDDLE OF NEXT WEEK. STRONGER WINDS WILL PERSIST OFF THE COLOMBIAN COAST. E TO SE WINDS WILL INCREASE OVER THE NW CARIBBEAN TUE AND WED...AS LOW PRES DIGS INTO THE NW GULF OF MEXICO. SEAS OF 8 TO 9 FT WITH FRESH NE SWELL WILL PERSIST OVER THE TROPICAL N ATLC MAINLY S OF 19N...AND OVER THE SW CARIBBEAN IN ASSOCIATION WITH THE STRONGER WINDS OFF THE COLOMBIAN COAST. SW NORTH ATLC S OF 31N W OF 55W... A PAIR OF COLD FRONTS ARE THE MAIN FEATURES THIS MORNING OVER THE DISCUSSION AREA. THE FIRST EXTENDS FROM 27N65W TO 22N74W IN THE SOUTHERN BAHAMAS. THE SECOND RUNS FROM 31N68W TO 23N80W...AND IS STARTING TO OVER THE FIRST ONE. BUOYS AND SHIP OBSERVATIONS JUST N OF THE AREA INDICATE SEAS OF 7 TO 8 FT...IN LINE WITH WAVEWATCH III INITIALIZATION. SEAS TO 8 FT IN W SWELL WILL LINGER THIS MORNING N OF 29N E OF 75W...THEN DECAY LESS THAN 8 FT LATER TODAY. AREAS OF SHOWERS AND THUNDERSTORMS ARE NOTED ALONG THE FIRST FRONT N OF 25N. THE FRONTS WILL MERGE TODAY AND STALL FROM ROUGHLY 26N65W TO EASTERN CUBA SUN AND MON...AND DISSIPATE BY TUE. HIGH PRES WILL BUILD N OF THE FRONT ALONG ROUGHLY 28N THROUGH SUN...THEN LIFT N OF THE AREA MON. SOUTHERLY WINDS START TO INCREASE TUE NIGHT AND WED OVER THE WATERS N OF GRAND BAHAMA...AHEAD OF A COLD FRONT THAT EMERGES OFF THE N FLORIDA COAST LATE WED. LOOKING AHEAD...THE COLD FRONT WILL REACH FROM 31N70W TO 28N81W ON THU...FOLLOWED BY N TO NE 20 KT WINDS...AND THE RIDGE AXIS SHIFTING S TO 26N. WARNINGS.. ATLC... .NONE. CARIBBEAN... .NONE. GULF OF MEXICO... .NONE. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ FORECASTER CHRISTENSEN