000 AGXX40 KNHC 060718 MIMATS MARINE WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 320 AM EDT SEP 06 2011 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... THERE IS GOOD AGREEMENT AMONG THE MODELS ON THE DEVELOPMENT OF A LOW PRES SYSTEM IN THE BAY OF CAMPECHE SOMETIME IN THE NEXT 24 HOURS ON THE SOUTHERN EDGE OF THE COLD FRONT STRETCHING FROM THE NE GULF INTO THE SW GULF. THE 00Z GFS...UKMET...AND ECMWF ALL LIFT THE LOW NORTHWARD FRI INTO THE WEEKEND...WITH THE ECMWF AN OUTLIER WITH ITS FAR N POSITION IN THE NORTHERN MIDDLE GULF BY SAT NIGHT. THE GFS IS THE FARTHEST W OF THE GLOBAL MODELS BY THAT TIME...BUT IS IN BETTER AGREEMENT WITH THE CONSENSUS BY KEEPING THE SYSTEM S OF 23N. THE GFS DEVELOPS THE STRONGEST WIND FIELD WITH THE SYSTEM COMPARED TO THE OTHER MODELS...DEVELOPING A TROPICAL STORM BY THE WEEKEND. CONFIDENCE IS STILL LOW IN THE DEVELOPMENT OF A NON-ELONGATED CLOSED CIRCULATION NEVERTHELESS A TROPICAL CYCLONE. WILL SIDE WITH THE MORE SOUTHERN MODEL CONSENSUS...BUT GO CONSIDERABLY WEAKER THAN THE GFS. THE PROGS WILL KEEP WINDS NO HIGHER THAN 25 KT. CARIBBEAN SEA AND TROPICAL N ATLC S OF 22N W OF 55W... A TROPICAL WAVE ALONG 50W FROM 12N TO 20N WILL TRACK NW IN THE WAKE OF HURCN KATIA...PASSING THROUGH THE NE CARIBBEAN WED EVENING THROUGH THU EVENING. 2340 UTC ASCAT SHOWS 20 KT WINDS IN ITS WAKE. THESE WINDS WILL REMAIN ON THE NORTHEASTERN PERIPHERY OF THE WAVE GRADUALLY DIMINISH AS THE SYSTEM APPROACHES THE TROPICAL N ATLC ZONE. THE WEAKER ECMWF IS PREFERRED AS IT SEEMS TO MATCH OBSERVATIONS BETTER THAN THE STRONGER GFS/MWW3. A TROPICAL LOW CURRENTLY NEAR 10N32W IS EXPECTED TO TRACK W-NW INTO THE TROPICAL N ATLC ZONE BY FRI AND THE NE CARIBBEAN OVER THE WEEKEND. THE GFS IS CONSIDERABLY FASTER AND MORE NORTHERLY THAN THIS PREFERRED TRACK WHICH IS CLOSEST TO THE ECMWF. THE GFS ALSO DEVELOPS THE SYSTEM INTO A TROPICAL STORM OVER THE NORTHERN TROPICAL N ATLC ZONE SAT. AGAIN...THE ECMWF APPEARS TO BE BETTER INITIALIZED THAN THE STRONGER GFS. OTHERWISE...THE CARIBBEAN WILL CONTINUE TO REMAIN RELATIVELY QUIET UNTIL THE ARRIVAL OF THIS TROPICAL LOW PRES SYSTEM THIS WEEKEND. SW ATLC S OF 31N W OF 55W... HURCN KATIA IS FORECAST IS CURRENTLY MOVING INTO THE SW N ATLC ZONE. THE GLOBAL MODELS ARE ALL SLIGHTLY SLOWER THAN THE OFFICIAL FORECAST BY WED NIGHT AS THE SYSTEM BEGINS TO MOVE N OF THE AREA. AS MENTIONED ABOVE...THE TROPICAL WAVE CURRENTLY ALONG 50W FROM 12N TO 20N WILL TRACK INTO THE ZONE THU WITH ITS ASSOCIATED WINDS DIMINISHED BELOW 20 KT AND SEAS MERGED WITH THOSE FROM KATIA BY THAT TIME. MORE UNCERTAINTY COME INTO PLAY WITH THE TROPICAL LOW CURRENTLY NEAR 10N32W. AS EXPLAINED IN THE SECTION ABOVE...THE MORE NORTHERLY AND STRONGER GFS SOLUTION IS NOT PREFERRED. THE FORECAST ABIDES MORE CLOSELY TO THE ECMWF WHICH KEEPS THE SYSTEM CENTER WELL S IN THE CARIBBEAN...BUT DOES BRING FRESH EASTERLY WINDS TO THE SOUTHERN PORTION OF THE ZONE OVER THE WEEKEND ON ITS NORTHERN PERIPHERY. WARNINGS... GULF OF MEXICO... .NONE. CARIBBEAN AND TROP N ATLC... .NONE. SW N ATLC... .AMZ080...HURRICANE WARNING N OF 24N E OF 70W. FOR ADDITIONAL INFORMATION PLEASE VISIT HTTP://WWW.HURRICANES.GOV/MARINE $$ FORECASTER SCHAUER