000 AGXX40 KNHC 290729 MIMATS MARINE WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 225 AM EST FRI JAN 29 2010 MARINE WEATHER DISCUSSION FOR GULF OF MEXICO...CARIBBEAN SEA AND SOUTHWEST NORTH ATLC S OF 31N W OF 55W GULF OF MEXICO... RIDGE EXTENDING ACROSS THE NORTHERN PORTION E OF ABOUT 90W WILL SHIFT E OF THE AREA THROUGH SAT MORNING AS LOW PRES DEVELOPING OVER S TEXAS WITH AN ASSOCIATED COLD FRONT BEGIN TO MOVE ENE TOWARDS THE WESTERN GULF. LATEST SATELLITE WATER VAPOR IMAGERY SHOWS THE A VERY VIGOROUS UPPER SHORTWAVE TROUGH EXTENDING FROM LOWER MID-WEST SW INTO NW MEXICO GIVING IMPETUS TO THE DEVELOPING LOW. GLOBAL MODELS AND EVEN THE REGIONAL NAM ARE PRETTY GOOD AGREEMENT THAT THE SURFACE LOW WILL TRACK NE JUST INLAND THE NW AND NORTHERN GULF COAST PLAINS TODAY INTO THIS EVENING DRAGGING THE COLD FRONT OFFSHORE THE TEXAS AND SW LOUISIANA COASTS THIS MORNING. AS THE LOW TRACKS FURTHER NE ACROSS THE SE U.S. TONIGHT THROUGH SAT...IT WILL SWEEP THE COLD FRONT ACROSS THE GULF TO A LINE FROM NEAR NE SE LOUISIANA TO WESTERN BAY OF CAMPECHE TONIGHT...FROM THE FLORIDA PANHANDLE TO EASTERN BAY OF CAMPECHE BY SAT AFTERNOON...THEN WEAKENING FROM NEAR FORT MYERS FLORIDA TO NE YUCATAN PENINSULA BY LATE SAT NIGHT INTO SUN MORNING AND CLEARING THE AREA LATER ON SUN. MODELS STILL KEYING ON STRONG RIDGE THAT BUILDS IN BEHIND THE FRONT THROUGH MON BEFORE WEAKENING TUE AS IT SLIDES E. TIGHT PRES GRADIENT CREATED BEHIND THE FRONT UNDER STRONG COLD ARTIC AIR ADVECTION IS EXPECTED TO FUNNEL IN STRONG NORTHERLY GALE FORCE WINDS OVER A PORTION OF THE SW GULF BEHIND THE FRONT BEGINNING TONIGHT...AND PROBABLY LASTING MUCH OF SAT MORNING BEFORE DIMINISHING. WINDS ELSEWHERE BEHIND THE ARE EXPECTED TO EACH THE 20-30 KT RANGE TODAY THROUGH MUCH OF SAT BEFORE DIMINISHING THROUGH SUN. NOAA WAVEWATCH BUILDS SEAS UP TO 13 FT BEHIND THE FRONT IN THE SW GULF SAT NIGHT INTO SUN MORNING. SEAS MAY REACH ABOUT 2 FEET HIGHER WITH WINDS OVER THE LONG FETCH AREA INTO THE SW GULF...SO WILL CONSIDER THIS FOR THIS FORECAST. WINDS AHEAD OF THE FRONT ARE EXPECTED TO INCREASE TO SW 20-25 KT MAINLY IN THE NORTHERN SECTIONS OF THE GULF. CONDITIONS BECOME TRANQUIL THROUGHOUT BEGINNING LATE SUN THROUGH TUE AS HIGH PRES RIDGING OVER THE GULF WEAKENS...HOWEVER MODELS HINT THAT SOME TROUGHINESS FROM THE REMNANTS OF THE FRONT MAY LINGER OVER THE SE PORTION OF THE GULF MON AND TUE PERHAPS INCREASING THE GRADIENT SOME THERE. SINCE THIS IS NOT TILL THE LONG TERM PORTION OF THE FORECAST...WILL EVALUATE UPDATED MODELS BEFORE BEING MORE SPECIFIC IN THE FORECAST WITH RESPECT TO TIMING AND DETAILS WITH THIS POSSIBLE SCENARIO. CARIBBEAN AND TROPICAL N ATLC W OF 55W... STRONG HIGH PRES CENTERED N OF THE CARIBBEAN CONTINUES TO RESULT IN A VERY TIGHT PRES GRADIENT OVER THE CARIBBEAN AND TROPICAL N ATLC WITH FRESH TO STRONG TRADES PERSISTING ACROSS THE MAJORITY OF THE BASIN. THE WIND OBSERVATIONS FROM A FEW SHIPS NOTED FROM FROM LATE LAST NIGHT INTO EARLY THIS MORNING WERE IN THE GALE FORCE RANGE OF NE-E 30-40 KT OVER THE FAR SOUTHERN WATERS S OF ABOUT 14N BETWEEN 69W-77W. WINDS ELSEWHERE WERE NE GENERALLY IN 20 KT RANGE WITH 25 KT WINDS AT TIMES NEAR THE WINDWARD PASSAGE. MAX SEAS WERE REPORTED UP TO 16 FT NEAR THE COAST OF COLOMBIA BY ONE OF THE SHIPS. THEREFORE...THE GALE WARNING REMAINS IN EFFECT FOR A PORTION OF THE SOUTHERN WATERS NEAR THE COAST OF S AMERICA THROUGH TODAY AS THEN THE HIGH TO THE N SHOULD WEAKEN ENOUGH ALLOWING FOR THE GRADIENT TO WEAKEN JUST ENOUGH FOR THE WINDS TO WEAKEN TO LESS THAN GALE FORCE. HOWEVER...ANY LONGEVITY OF THE STRONG HIGH WILL EXTEND THE LIFETIME OF THESE GALE WINDS OVER THESE WATERS. AS THE ABOVE MENTIONED GULF OF MEXICO COLD FRONT MAKES HEADWAY TOWARDS FLORIDA AND THE SW N ATLC DURING THE NEXT 24-36 HRS... WINDS OVER MUCH OF THE NW CARIBBEAN WILL VEER AROUND TO THE SE AND BECOME LIGHTER THAN THE CURRENT SPEEDS OF 20 KT. THE COLD FRONT IS FORECAST TO MOVE INTO THE FAR NW CARIBBEAN SEA LATE SAT NIGHT INTO EARLY SUN...THEN IS EXPECTED TO WEAKEN AND SLOW DOWN. IT SHOULD THEN WASH OUT BY LATE SUN AS GFS AND ECMWF AGREE ON THIS SCENARIO. WINDS BEHIND THE FRONT MAY BRIEFLY BECOME NE 20 KT THROUGH THE YUCATAN CHANNEL BEFORE THE FRONT BECOMES DIFFUSED. N SWELLS UP TO 9 FT WERE NOTED ACROSS THE NORTHERN PORTION OF THE TROPICAL N ATLC EARLY THIS MORNING...BUT THEY WILL SUBSIDE THROUGH THIS AFTERNOON. LATEST MODEL GUIDANCE SUGGESTS THAT BY TUE WINDS WILL BE RATHER LIGHT OVER MOST OF THE AREA...WITH THE EXCEPTION OF THE S CENTRAL CARIBBEAN WATERS NEAR THE COAST OF S AMERICA WHERE ELY WINDS MAY BE IN THE RANGE OF 20-25 KT. SW N ATLC S OF 31N W OF 55W... A 1024 HIGH WAS ANALYZED NEAR 29N73W WITH A RIDGE W ACROSS FLORIDA AND INTO THE GULF OF MEXICO. THE HIGH IS KEEPING LIGHT WINDS OVER MUCH OF THE AREA...EXCEPT FOR THE SE WATERS E OF THE BAHAMAS WHERE A TIGHTER GRADIENT IS ALLOWING FOR NE-E WINDS OF 15-20 KT. THE HIGH IS STILL FORECAST TO SLIDE E OF THE AREA TONIGHT INTO SAT AS THE ABOVE MENTIONED GULF OF MEXICO COLD FRONT APPROACHES FLORIDA AND THE FAR WESTERN WATERS. IN ADVANCE OF THE APPROACHING COLD FRONT...WINDS WILL SHARPLY VEER OVER THE NW PORTION TONIGHT INTO SAT MORNING. THE FRONT SHOULD MOVE OFF THE NE FLORIDA COAST EARLY SAT EVENING...AND REACH FROM NEAR 31N75W TO S FLORIDA LATE SAT NIGHT...FROM 31N73W TO JUST OFFSHORE THE SE FLORIDA COAST AND THROUGH THE STRAITS OF FLORIDA SUN MORNING...FROM NEAR 30N65W TO THE SE BAHAMAS AND EASTERN CUBA BY SUN EVENING WHILE WEAKENING...THEN CONTINUE TO WEAKEN OVER THE FAR SE WATERS MON AND TUE AS POSSIBLE LOW/TROUGH EVOLVES FROM ITS REMNANTS OVER OR NEAR THE NW BAHAMAS...AND A COASTAL TROUGH FORM OFF N AND CENTRAL FLORIDA COASTS EXTENDING TO OFF THE SE U.S. COAST. THIS REMAINS UNCERTAIN AT THE PRESENT TIME. POSSIBLE GALE FORCE WINDS ARE EXPECTED AHEAD OF THE FRONT N OF 30N AS SEEN WITH PREVIOUS FRONTAL EVENTS THROUGH THESE WATERS. BEHIND THE FRONT WINDS BECOME NW-N AT 20-25 KT ON SAT...THEN WEAKEN QUICKLY INTO SUN AND FURTHER ON MON AND TUE AS THEY TURN AROUND TO THE NE-E. WARNINGS... ATLC... .AMZ080...GALE CONDITIONS EXPECTED N OF 30N E OF FRONT SAT NIGHT AND SUN. CARIBBEAN... .AMZ084 AND AMZ086...GALE WARNING FROM 11N TO 13N BETWEEN 70W AND 77W. GULF OF MEXICO... .GMZ082...GALE WARNING S OF 22N W OF FRONT TONIGHT AND SAT. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ FORECASTER AGUIRRE