000 AGXX40 KNHC 200858 AAA MIMATS MARINE WEATHER DISCUSSION...UPDATED NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 500 AM EDT MON SEP 20 2010 UPDATED WARNINGS AND IGOR INFORMATION 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... A TROUGH WILL LINGER IN THE FAR W GULF WHILE RIDGING REMAINS JUST N OF THE WATERS THROUGH THE PERIOD. MODERATE TO FRESH TRADES AND SEAS OF 3 TO 6 FT WILL PREVAIL ACROSS THE MAJORITY OF THE FORECAST AREA THROUGH THE PERIOD. EXPECT GUSTS TO 25 KT AND HIGHER SEAS IN THE STRAITS OF FLORIDA. ALSO DIURNALLY DRIVEN N-NE 20 KT WINDS WILL OCCUR EACH EVENING ALONG THE YUCATAN COAST. SW N ATLC... HURRICANE IGOR IS NOW WELL N OF THE AREA...LOCATED NEAR 34.2N 64.4W OR ABOUT 135 MILES N OF BERMUDA...957 MB MAXIMUM WINDS 65 KT GUSTS 80 KT MOVING NNE OR 025 DEGREES AT 17 KT. BERMUDA REPORTED A GUST TO 81 KT WITH A MINIMUM PRESSURE OF 965 MB SUN EVENING. CONDITIONS WILL CONTINUE TO GRADUALLY IMPROVE DURING THE NEXT 24 HOURS AS IGOR MOVES FARTHER AWAY FROM BERMUDA WHILE BEGINNING TO TRANSITION TO AN EXTRATROPICAL SYSTEM. THE HURRICANE WARNING FOR THE NE PORTION OF THE AREA HAS BEEN REPLACED WITH A TROPICAL STORM WARNING N OF 29N E OF 68W AS HURRICANE FORCE WINDS ARE NOW CONFINED TO N OF 33N. THE SOUTHERN EXTENT OF THE 50 KT WIND RADII IS LOCATED NEAR 32N SO HAVE GONE WITH WORDING OF 45 KT GUSTS 55 KT FOR HIGHEST WINDS THIS MORNING OVER FORECAST WATERS. TROPICAL STORM FORCE WINDS WILL DIMINISH OVER THE WATERS BY 1800 UTC THIS AFTERNOON. LARGE AND DANGEROUS SWELLS GENERATED ON THE BACKSIDE OF IGOR WILL CONTINUE TO EFFECT THE SE U.S. COAST AND THE BAHAMAS WITH A HIGH RISK OF RIP CURRENTS THROUGH THE WEEK...EVEN AFTER IGOR MOVES WELL N-NE OF THE AREA. ATLC RIDGING WILL DEVELOP IN THE WAKE OF IGOR JUST N OF THE AREA WITH FRESH TO STRONG EASTERLY TRADES ACROSS THE WATERS WED THROUGH FRI. CARIBBEAN SEA AND TROPICAL N ATLC... THE MONSOON TROUGH REMAINS OVER THE SW CARIBBEAN SEA AND EXTENDING W OF THE AREA INTO THE E PACIFIC BASIN. SCATTERED SHOWERS AND ISOLATED TSTMS WILL CONTINUE TO OCCUR IN THE VICINITY OF THE TROUGH WITH LIGHT AND VARIABLE WINDS S OF THE TROUGH AXIS. OTHERWISE...A SURFACE RIDGE WILL CONTINUE TO BUILD ALONG OR JUST N OF THE TROPICAL N ATLC THROUGH THE WEEK IN THE WAKE OF HURRICANE IGOR. A WIND SURGE ALONG THE LEADING EDGE OF THE SURFACE RIDGE AIDED IN THE DEVELOPMENT OF A SURFACE TROUGH YESTERDAY ON THE CYCLONIC SHEAR SIDE. THIS TROUGH WILL MOVE WESTWARD ACROSS THE TROPICAL N ATLC WATERS MON THROUGH EARLY TUE BEFORE MOVING THROUGH THE CARIBBEAN WATERS WED THROUGH FRI. A TIGHT PRESSURE GRADIENT BETWEEN THIS TROUGH AND THE RIDGE TO THE NORTH WILL RESULT IN FRESH TO MODERATE EASTERLY TRADES SPREADING FROM E TO W ACROSS THE BASINS THROUGH THE PERIOD WITH SEAS BUILDING TO 11 FT OVER THE N PORTION OF THE TROPICAL N ATLC BASIN AND NW CARIBBEAN BY THE END OF THE WEEK DUE TO THE PERSISTENT AND LENGTHENING EASTERLY FETCH. WARNINGS... SW N ATLC... .TROPICAL STORM WARNING N OF 29N E OF 68W. CARIBBEAN... .NONE. TROPICAL N ATLC... .NONE. GULF OF MEXICO... .NONE. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ FORECASTER LEWITSKY