000 AGXX40 KNHC 250705 MIMATS MARINE WEATHER DISCUSSION NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 305 AM EDT THU JUN 25 2009 MARINE WEATHER DISCUSSION FOR THE GULF OF MEXICO...CARIBBEAN SEA AND SOUTHWEST NORTH ATLC S OF 31N W OF 55W. ATLC... THE DEEP LAYER TROUGH IN THE WESTERN ATLC WILL WEAKEN SOMEWHAT OVER THE NEXT FEW DAYS AS THE ENERGY IN ITS LEADING EDGE LIFTS NORTHEASTWARD INTO THE CENTRAL N ATLC AND THE UPPER RIDGE TO ITS SE SHIFTS WESTWARD INTO THE SOUTHERN BAHAMAS. HOWEVER...THE MEAN TROUGH OVER THE WESTERN ATLC WILL PERSIST FOR SOME TIME AS A NEW BATCH OF SHORTWAVE ENERGY...CURRENTLY OVER CANADA S OF HUDSON BAY...PASSES EAST-SOUTHEASTWARD THROUGH NEW ENGLAND OVER THE WEEKEND...RELOADING THE TROUGH AND SENDING A SURFACE COLD FRONT JUST NORTH OF THE SW N ATLC OFFSHORE ZONE. WHILE THE COLD FRONT CURRENTLY IS NOT EXPECTED TO MOVE INTO FORECAST WATERS...THE INCREASED PRESSURE GRADIENT BETWEEN A PREFRONTAL TROUGH DEVELOPING OVER THE ZONE FRI AND THE BUILDING SUBTROPICAL RIDGE WILL INCREASE WINDS OVER MUCH OF THE ZONE...ESPECIALLY N OF 27N...OVER THE WEEKEND. THE MODELS ARE IN RELATIVELY GOOD AGREEMENT ON THE PATTERN...WITH THE GFS AND NOGAPS SLIGHTLY MORE NORTHERLY WITH THE RIDGE AXIS AND PRES GRADIENT OVER THE REGION BY THE END OF THE PERIOD THAN THE UKMET...CMC...AND 12Z ECMWF. OVER THE TROPICAL N ATLC...THE TROPICAL WAVE ALONG 56W S OF 14N WILL MOVE W INTO THE CARIBBEAN BY FRI MORNING. THE 0136 ASCAT PASS SHOWS A BELT OF 20 TO 25 KT WINDS AHEAD OF THE WAVE FROM 12N TO 15N THAT IS CORROBORATED BY SURFACE OBSERVATIONS. A SECOND TROPICAL WAVE...ALONG 30W S OF 15N BASED ON THE 2016 UTC QUIKSCAT PASS...IS EXPECTED TO MOVE THROUGH THE TROPICAL N ATLC ZONE SUN. THIS WAVE SHOULD CONTINUE W AT 15 KT AS THE RIDGE TO ITS N SHIFTS SE AND THE UPPER LOW CURRENTLY CENTERED NEAR 21N50W WEAKENS AND BECOMES ABSORBED IN THE LEADING EDGE OF THE AMPLIFYING WESTERN ATLC TROUGH THE BEGINNING OF NEXT WEEK. CARIBBEAN... THE TROPICAL WAVE ALONG 72W WILL MOVE WEST AROUND 10 KT OVER THE REMAINDER OF THE FORECAST PERIOD...REACHING NICARAGUA/HONDURAS S OF 20N ON SAT. THE WAVE IS BEING INFLUENCED NORTHWARD AS IT ROUNDS THE WESTERN EDGE OF THE SUBTROPICAL RIDGE WHICH HAS BEEN WEAKENED BY THE ANOMALOUSLY STRONG TROUGH OVER THE WESTERN ATLC. ANOTHER TROPICAL WAVE ALONG 55W S OF 14N WILL MOVE THROUGH THE EASTERN CARIBBEAN FRI/SAT. BY EARLY NEXT WEEK...THE WAVE WILL LIKELY TAKE A MORE NORTHERLY TURN AS IT MOVES INTO THE CENTRAL/WESTERN CARIBBEAN AND ENCOUNTERS WEAKNESS IN THE SUBTROPICAL RIDGE TO IT N. GULF OF MEXICO... ANOTHER QUIET FORECAST PERIOD IS IN STORE FOR THE GULF OF MEXICO. THE SUBTROPICAL ATLC RIDGE AXIS...CURRENTLY SUPPRESSED TO THE SOUTH OF THE SW N ATLC ZONE...WILL BUILD W AND MOVE NORTHWARD THROUGH SAT...SETTLING AROUND 26N. THE RIDGE WILL THEN MOVE BACK TO THE S AND WEAKEN AS ANOTHER ROUND OF MID LATITUDE ENERGY RELOADS THE TROUGH IN THE WESTERN ATLC EARLY NEXT WEEK. THE TROPICAL WAVE CURRENTLY ALONG 72W SHOULD PASS THROUGH THE BAY OF CAMPECHE ON MON...STRETCHING NORTHWARD AS IT TRAVELS WEST DUE TO WEAKNESS IN THE SUBTROPICAL RIDGE. WARNINGS ATLC... .NONE. CARIBBEAN... .NONE. GULF OF MEXICO... .NONE. FORECASTER SCHAUER CLARK. TROPICAL PREDICTION CENTER.