000 AGXX40 KNHC 220642 MIMATS MARINE WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 245 AM EDT THU OCT 22 2009 MARINE WEATHER DISCUSSION FOR GULF OF MEXICO...CARIBBEAN SEA AND SOUTHWEST NORTH ATLC S OF 31N W OF 55W. GULF OF MEXICO... HIGH PRES RIDGE DOMINATES THE GULF OF MEXICO PRODUCING E TO SE WINDS OF 20 KT OVER MUCH OF THE REGION. SFC DATA AND AN EARLIER QSCAT PASS CONFIRMED THESE WIND SPEEDS. THE HIGH WILL MOVE MAINLY E THROUGH FRI TOWARD BERMUDA AND GRADUALLY WEAKEN. A COLD FRONT WILL MOVE INTO THE NW GULF THU NIGHT WITH SLY RETURN FLOW OF 20 TO 25 KT AND SEAS OF UP TO 9 FT AHEAD OF IT. THE FRONT WILL REACH FROM SE LOUISIANA TO THE NEAR TAMPICO MEXICO FRI MORNING AND FROM THE FLORIDA BIG BEND TO THE BAY OF CAMPECHE SATURDAY MORNING. FRONT WILL THEN BECOME DIFFUSE OVER THE FAR E PORTION AND FLORIDA SUN AND MON. NLY WINDS OF 20 KT AND BUILDING SEAS OF 8 FT ARE EXPECTED IN THE WAKE OF THE FRONT FRI AND SAT THEN DECREASE TO 10-15 KT ON SUN AND MON. HIGH PRES OVER THE NORTHERN WATERS WILL QUICKLY SHIFT NE OF THE AREA SUN INTO MON AS ANOTHER COLD FRONT MOVES INTO THE FAR NW GULF MON. CARIBBEAN AND TROPICAL N ATLANTIC W OF 55W... A BROAD AREA OF LOW PRES OVER THE SW CARIBBEAN SEA WILL REMAIN NEARLY STATIONARY THROUGH FRI...THEN BEGIN TO DRIFT IN A GENERAL NORTHWARD DIRECTION FRI NIGHT THROUGH SUN IN RESPONSE TO A WEAK FRONT THAT MOVES ACROSS CENTRAL FLORIDA. THIS SYSTEM REMAINS POORLY ORGANIZED AND DEVELOPMENT...IF ANY...WILL BE SLOW TO OCCUR. THERE IS A LOW CHANCE...LESS THAN 30 PERCENT...OF THIS SYSTEM BECOMING A TROPICAL CYCLONE DURING THE NEXT 48 HOURS. LIGHT TO MODERATE TRADES WILL CONTINUE OVER THE BASIN THROUGH FRI...INCREASING TO 20 KT NEAR THE COAST OF SOUTH AMERICA LATE FRI THROUGH SUN AS THE AREA OF LOW PRES OVER THE SW CARIBBEAN DRIFTS NWD. SW N ATLC S OF 31N AND W OF 65W... HIGH PRES CENTERED NEAR CAPE HATTERAS EXTENDS A RIDGE OVER THE SW N ATLC. PRES GRADIENT BETWEEN THIS HIGH AND A WEAKENING FRONTAL TROUGH OVER THE SE PORTION OF THE AREA IS PRODUCING A BELT OF NE WINDS 20-25 KT OVER MUCH OF THE AREA INCLUDING THE STRAITS OF FLORIDA. AN ASCAT PASS FROM AROUND 0220 UTC INDICATED THESE WIND SPEEDS. THE RIDGE WILL SLIDE E TO THE FAR NE WATERS SUN AND MON AHEAD OF A WEAKENING COLD FRONT. BROAD LOW PRES MAY DEVELOP OVER THE BAHAMAS FRI THROUGH MON...AND IS FORECAST BY THE COMPUTER MODELS TO MOVE ACROSS THE BAHAMAS AND E OF FLORIDA DURING THIS TIME FRAME AHEAD OF ANOTHER COLD FRONT EXPECTED TO APPROACH THE SE U.S. COAST LATE SAT. WILL HAVE TO WAIT TO SEE WHETHER THIS SYSTEM UNDERGOES A DEVELOPING TREND DURING THE NEXT 24-48 HOURS TO GET A BETTER HANDLE ON CHANGES REQUIRED FOR WINDS AND SEAS FOR THESE WATERS. THE 22/000O UTC RUN OF THE NOAA WAVE WATCH III INDICATES THAT SEAS MAY INCREASE TO 12 FT IN THE NE QUADRANT OF THE LOW PRES WITH WINDS IN THE 20 TO 25 KT RANGE ACCORDING TO THE GFS MODEL. WARNINGS... ATLC... .NONE. CARIBBEAN... .NONE. GULF OF MEXICO... .NONE. $$ FORECASTER GR