000 AGXX40 KNHC 151926 MIMATS MARINE WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 330 PM EDT TUE SEP 15 2009 GULF OF MEXICO... AN UPPER TROUGH OVER THE CENTRAL CONUS IS PROVIDING SOME SUPPORT FOR A SLOW MOVING COLD FRONT THAT EXTENDS FROM SE LOUISIANA TO NEAR BROWNSVILLE TEXAS. SURFACE OBSERVATIONS AND A 12Z QUIKSCAT PASS REVEAL 15-20 KT SW WINDS WITHIN 180 NM EAST OF THE FRONT AND 10-15 KT W WINDS WEST OF THE FRONT. MAXIMUM SEAS ARE ESTIMATED TO BE 5 FT NEAR 28N90W...IN AGREEMENT WITH THE WAVE WATCH SHORT TERM GUIDANCE. WINDS ARE LIGHT AND VARIABLE ACROSS MUCH OF THE SOUTHERN WATERS. THE FRONT IS FORECAST TO MOVE LITTLE OVER THE NEXT COUPLE OF DAYS AS THE SURFACE LOW REMAINS INLAND OVER LOUISIANA. CONSEQUENTLY...LITTLE CHANGE IS FORECAST IN WINDS AND SEAS...BUT CONDITIONS WILL LIKELY WEAKEN/SUBSIDE SLIGHTLY BY LATE THU. THE FRONT WILL GRADUALLY DISSIPATE THIS WEEKEND ALLOWING HIGH PRES RIDGING TO BUILD ACROSS THE REGION. CARIBBEAN AND TROPICAL NORTH ATLANTIC... SURFACE AND SCATTEROMETER DATA SHOW A SMALL AREA OF 15-20 KT EASTERLY TRADES OVER THE USUAL ENHANCED LOCATIONS...THE SOUTH CENTRAL CARIBBEAN AND THE GULF OF HONDURAS. WINDS ARE LIGHT ELSEWHERE...DUE TO BROAD LOW PRESSURE OVER THE WESTERN ATLANTIC. MAIN FEATURE OF CONCERN FOR THE FORECAST IS THE REMNANTS OF FRED LOCATED EAST OF THE AREA NEAR 19N46W. THE GLOBAL MODEL GUIDANCE IS SPLIT INTO TWO GROUPS. THE GFS/ECMWF QUICKLY WEAKEN THE REMNANT LOW INTO A TROUGH TOMORROW AS IT APPROACHES 55W. THE UKMET/NOGAPS/CMC MODELS TAKE IT ACROSS 55W AND EVEN 65W AS A CLOSED LOW. STILL PREFER THE GFS/ECMWF SOLUTIONS BUT WILL CONTINUE TO MONITOR MODEL TRENDS. REGARDLESS...THIS TROUGH OR LOW IS FORECAST TO MOVE NEAR OR NORTH OF 20N...WHICH WILL CAUSE LIGHTER THAN NORMAL TRADES OVER MUCH OF THE CARIBBEAN AND TROPICAL N ATLC ZONES. SOUTHWEST NORTH ATLANTIC... SATELLITE IMAGES...SURFACE OBSERVATIONS...AND SCATTEROMETER DATA SHOW A CLOSED BUT ELONGATED SURFACE LOW NEAR 28N74W. A WARM FRONT EXTENDS NORTHEASTWARD FROM THE LOW THROUGH 31N68W AND A TROUGH EXTENDS SOUTHWESTWARD ACROSS THE CENTRAL BAHAMAS. S TO SW WINDS NEAR 20 KT EXIST WITHIN 300 NM E OF THE FRONT FROM 23N TO 29N AND NE 15-20 KT WINDS ARE PRESENT WITHIN 120 NM W OF THE FRONT FROM 29N TO 31N. GLOBAL MODELS ARE IN FAIR AGREEMENT IN TAKING THE LOW NORTHWARD...MOVING NORTH OF 31N LATE TOMORROW. HOWEVER...THE TRAILING TROUGH WILL REMAIN ACROSS THE AREA FOR A FEW MORE DAYS EXTENDING FROM 31N70W TO THE CENTRAL BAHAMAS LATE TOMORROW...31N70W TO THE NW BAHAMAS THU...AND THEN DISSIPATE BY FRI. THE PRESSURE GRADIENT...BETWEEN THE SUBTROPICAL RIDGE OVER THE CENTRAL ATLANTIC AND THE TROUGH...WILL PRODUCE 20 KT SLY WINDS WITHIN 300 NM E OF THE TROUGH OVER THE NEXT DAY OR TWO. WARNINGS ATLC... .NONE. CARIBBEAN... .NONE. GULF OF MEXICO... .NONE $$ FORECASTER CANGIALOSI