000 AGXX40 KNHC 250730 MIMATS MARINE WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 230 AM EST WED FEB 25 2009 MARINE WEATHER DISCUSSION FOR GULF OF MEXICO... CARIBBEAN SEA AND SOUTHWEST NORTH ATLC S OF 31N W OF 55W. GULF OF MEXICO... SOUTHERLY RETURN FLOW BETWEEN TROUGHING OVER THE SOUTHERN PLAINS AND RIDGING IN THE EASTERN GULF WILL KEEP WINDS AROUND 20 KT IN THE NW GULF UNTIL THE COLD FRONT APPROACHES SAT. THE RIDGE AXIS SHOULD BECOME MORE EAST TO WEST ORIENTED OVER THIS TIME PERIOD. CONFIDENCE IN THE FORECAST DETAILS WANES BY THU/FRI AS THE FLOW BECOMES MORE ZONAL...BUT THE MODELS AGREE ON AMPLIFYING THE PATTERN BY CARRYING ENERGY SOUTHWARD THROUGH THE MISSISSIPPI VALLEY/SOUTHEAST OVER THE WEEKEND. AT THE SAME TIME...THE MODELS INTENSIFY THE DEEP LAYER RIDGE AS IT PASSES NE OF BERMUDA. THE PATTERN HAS CALLED FOR THESE TROUGHS TO PASS NORTHWARD ALONG THE WESTERN EDGE OF THE SUBTROPICAL RIDGE RATHER THAN DISPLACING IT SIGNIFICANTLY. THE GFS IS MORE PERSISTENT WITH THE RIDGING THAN THE ECWMF...WITH THE GFS FORCING THE SURFACE WAVE ALONG THE COLD FRONT IMPACTING THE GULF OF MEXICO OVER THE WEEKEND FARTHER N OVER THE SE THAN THE ECMWF. HOWEVER...THE GFS IS NOT AS FAR N AS THE UKMET SOLN. CONFIDENCE IS LOW...BUT THE MIDDLE-OF-THE-ROAD GFS SOLUTION LOOKS REASONABLE FOR NOW. CARIBBEAN... THE DEEP LAYER TROUGH SUPPORTING THE COLD FRONT CURRENTLY MAKING ITS WAY THROUGH THE SW N ATLC INTO EASTERN CUBA HAS ENCOUNTERED THE SUBTROPICAL RIDGE....WEAKENING THE PRESSURE GRADIENT BETWEEN THE RIDGE AND THE 1011 MB LOW OVER COLOMBIA. THE ASCAT PASSES AROUND 0120 AND 0300 UTC SHOWED WINDS HAD SUBSIDED TO 20 KT OR LESS EVERYWHEREH S OF 18N EXCEPT THE BETWEN 70W AND 78W...ESPECIALLY NEAR THE COAST OF COLOMBIA. WINDS BEHIND THE COLD FRONT PASSING THROUGH EASTERN CUBA HAVE INCREASED AS THE NEW HIGH PRESSURE BEHIND THE COLD FRONT PASSES OFF THE EAST. EXPECT WINDS TO STAY IN THE 20 KT RANGE THROUGH THU. HOWEVER...AS THE FRONT EDGES EASTWARD...THE PRESSURE GRADIENT WILL RELAX SOMEWHAT OVER THE REST OF THE CARIBBEAN...AND WINDS SHOULD BEGIN TO DIMINISH GENERALLY TO AROUND 15 KT S O 18N E OF 80W WED-SUN. THE NEXT COLD FRONT WILL APPROACH THE NW CARIBBEAN SUN...WITH THE GFS THE PREFERRED MODEL AS EXPLAINED ABOVE. ATLC... THE PERSISTENT SUBTROPICAL RIDGE IS FORCING THE LONG-WAVE TROUGHS MOVING OFFSHORE NORTHEASTWARD OVER THE NW EDGE OF THE RIDGE. THE PORTION OF THE FRONT S OF 26N CURRENTLY MOVING THROUGH THE SW N ATLC IS HAVING A HARD TIME MAKING IT E OF 65W. ACCORDING TO THE ASCAT PASS AT 0124 UTC...WINDS HAVE BUILT TO 20 TO 25 KT BEHIND THIS FRONT AS THE NEW HIGH PRESSURE MOVING OFF THE E COAST BEHIND THE FRONT BUILDS SOUTHWARD...INCREASING THE PRESSURE GRADIENT OVER S FL AND THE BAHAMAS. THE DEEP LAYER TROUGH WILL CONTINUE TO EDGE EASTWARD...SLACKENING THE TRADES OVER WESTERN WATERS S OF 20N...BUT THE FRONT SHOULD REMAIN RELATIVELY STATIONARY UNTIL FRI WHEN THE ENTIRE PATTERN SHOULD BECOME MORE AMPLIFIED...DIRECTING SOME OF THE ENERGY ASSOCIATED WITH THE TAIL END OF THIS BOUNDARY NORTHWARD...LIKELY DEVELOPING A SURFACE WAVE ALONG THE BOUNDARY...AS IT BEGINS TO MOVE OFF TO THE NORTHEAST. WHILE THE GFS WAS PREFERRED OVER THE GULF OF MEXICO...BELIEVE IT HAS LATCHED ONTO MULTIPLE WAVES OVER THE ATLC. THERE IS BETTER AGREEMENT ON AMPLYING THE ONE NEAR 25N 60W. ATLANTIC... NONE. CARIBBEAN... NONE. GULF OF MEXICO... NONE. FORECASTER SCHAUER CLARK. TROPICAL PREDICTION CENTER.