000 AGXX40 KNHC 060730 MIMATS MARINE WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 230 PM EST THU NOV 06 2009 MARINE WEATHER DISCUSSION FOR GULF OF MEXICO...CARIBBEAN SEA AND SOUTHWEST NORTH ATLC S OF 31N W OF 55W. GULF OF MEXICO... TIGHTENING PRES GRADIENT ACROSS THE GULF DUE TO THE PRES BETWEEN TROPICAL DEPRESSION IDA S OF THE AREA AND STRONG HIGH PRES TO THE N IS RESULTING IN INCREASING WINDS ACROSS JUST ABOUT THE ENTIRE GULF AS SEEN IN BUOY REPORTS FROM LATE LAST NIGHT AND INTO THIS MORNING. NE WINDS OF 20-25 KT ARE PRESENTLY BEING REPORTED S OF 28N E OF 92W AND S OF 26N W OF 92W. DUE TO THE DURATION AND LARGE ELY FETCH OF THESE WINDS...SEAS HAVE ALREADY BUILD UP TO 13 FT OVER THE CENTRAL PORTION OF THE MIDDLE GULF. SEAS ELSEWHERE ARE IN THE RANGE OF 8-12 FT WITH THE EXCEPTION OF THE NW AND N WATERS WHERE SEAS ARE LOWER...IN THE RANGE OF 4-6 FT. THE PARENT HIGH CENTER N OF THE AREA SLIDING E THROUGH MON AND TROPICAL DEPRESSION IDA FORECAST TO STRENGTHEN INTO A TROPICAL AS IT MOVES THROUGH THE NW CARIBBEAN APPROACHING THE FAR S CENTRAL GULF NEAR THE YUCATAN PENINSULA MON...THE STRONG GRADIENT IS EXPECTED TO CONTINUE PRODUCING VERY ROUGH MARINE CONDITIONS FOR JUST ABOUT THE ENTIRE GULF. GLOBAL MODELS AND THE REGIONAL NAM CONTINUE TO SUGGEST THAT LOW PRES WILL SPIN UP IN THE VICINITY OF THE BAY OF CAMPECHE TODAY...AND SLOWLY MOVE N THROUGH THE WEEKEND. THERE ARE TIMING DIFFERENCES WITH SOME OF THE MODELS WITH RESPECT TO THE DEVELOPMENT OF THIS LOW SO WILL GFS AND UKMET BEING THE FASTEST IN TAKING THE LOW N. WILL LEAN TOWARDS THE EUROPEAN AND NAM FOR FUTURE TRACK OF THIS LOW FOR THIS FORECAST. TIGHT PRES GRADIENT PINCHED OFF OVER THE FAR SW GULF IS INDUCING GALE FORCE WINDS S OF 21N W OF 94W. EXPECT THESE WINDS TO LAST THROUGH AT LEAST SAT AFTERNOON...BUT COULD BE PROLONGED TO NEW AND DEEPER LOW THAT POSSIBLY FORMS. SW N ATLC S OF 31N AND W OF 55W... A WEAK AND DIFFUSE COLD FRONT IS IN PLACE OVER THE NE PORTION OF THE AREA FROM 31N67W TO 26N74W. THIS FRONT WILL DISSIPATE TONIGHT. IN THE UPPER LEVELS A SHORTWAVE TROUGH IS EXITING THE EASTERN SEABOARD THIS AFTERNOON...AND HAS PUSHED A STRONG COLD FRONT OFF THE EAST COAST OF THE U.S. TODAY. A STRONG NORTHERLY WIND SURGE SETS UP BEHIND THE FRONT TONIGHT THROUGH SUN AS THE COMBINATION OF HIGH PRES BUILDING OVER THE SE U.S. STATES AND A LOW DEEPENING OFF THE MID ATLANTIC COAST RESULTS IN A TIGHT PRESSURE GRADIENT. NORTHERLY SWELL GENERATED BY THESE WINDS WILL PROPAGATE THROUGH THE AREA BUILDING SEAS UP TO 14 FT OVER THE N PORTION FRI NIGHT THROUGH SUN. THE LONG PERIOD SWELLS WILL CONTINUE SOUTHWARD ACROSS THE WESTERN PORTION THROUGH THE FIRST HALF OF NEXT WEEK. CARIBBEAN AND TROPICAL N ATLANTIC W OF 55W... T.S. IDA WAS LOCATED NEAR 13.1N 83.7W THIS AFTERNOON WITH ESTIMATED WINDS OF 55 KT. IDA HAS MADE LANDFALL ALONG THE E COAST OF NICARAGUA. SHORT PERIOD WAVES OF 8 TO 12 FT (WITH MAX SEAS OF 19 FT) WILL AFFECT THE CARIBBEAN WATERS S OF 18N W OF 81W. IDA IS MOVING TOWARD THE NORTHWEST AT 3 KT. THIS FEATURE IS FORECAST TO EXIT THE COAST OF HONDURAS ON SATURDAY AS A TROPICAL DEPRESSION...AND THEN INTENSIFY INTO A TROPICAL STORM ON SUNDAY OVER THE WESTERN CARIBBEAN WATERS. OTHERWISE...SUBTROPICAL HIGH PRES REMAINS CENTERED WELL N OF THE AREA WITH A WEAK PRESSURE GRADIENT CONTINUING TO PREVAIL ACROSS THE CARIBBEAN RESULTING IN PERSISTENT RARE LIGHT TO MODERATE TRADES. THE HIGH WILL REMAIN CENTERED WELL N OF THE AREA THROUGH THE WEEKEND AND INTO EARLY NEXT WEEK ALLOWING FOR THE WEAK GRADIENT TO CONTINUE. NORTHERLY SWELL OF UP TO 8 FT WILL START TO PROPAGATE THROUGH THE WINDWARD PASSAGES BY MON NIGHT. WARNINGS... ATLC... .NONE. CARIBBEAN... .AMZ084...TROPICAL STORM WARNING FROM 17N TO 18N BETWEEN 84W 85.5W. GULF OF MEXICO... .GMZ082...GALE WARNING S OF 21N W OF 94W. $$ FORECASTER AGUIRRE