000 AGXX40 KNHC 130718 MIMATS MARINE WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 318 AM EDT WED AUG 13 2014 MARINE WEATHER DISCUSSION FOR THE GULF OF MEXICO...CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W...AND THE SW N ATLANTIC INCLUDING THE BAHAMAS. ...GULF OF MEXICO... MODEL PREFERENCE: LATEST GFS BLENDED WITH PREVIOUS/OFFICIAL FORECAST. LATEST MWW3 BLENDED WITH PREVIOUS/OFFICIAL FORECAST HIGH CONFIDENCE. A WEAK RIDGE EXTENDING FROM SOUTH FLORIDA TO NORTHERN MEXICO WILL MEANDER ACROSS THE GULF WATERS THROUGH SUN NIGHT. THIS RIDGE PATTERN WILL MAINTAIN MAINLY LIGHT TO GENTLE BREEZE AND SEAS GENERALLY UNDER 4 FT ACROSS MUCH OF THE GULF REGION. A WEAK FRONTAL BOUNDARY WILL SINK INTO THE N COASTAL WATERS THIS MORNING WHERE IT WILL MEANDER THROUGH THU THEN REMNANTS LIFT N AND INLAND. MARINE GUIDANCE SUGGESTS INCREASING SLY RETURN FLOW ACROSS THE WESTERN GULF FRI NIGHT INTO SAT DUE TO THE PRES GRADIENT BETWEEN THE RIDGE AND A LOW PRES SYSTEM FORECAST TO MOVE ACROSS ROCKIES AND INTO CENTRAL PLAINS. EXPECT INCREASING SE-S WINDS OF 15-20 KT ACROSS THE WESTERN GULF WATERS MAINLY N OF 22N W OF 94W DURING THE UPCOMING WEEKEND. WINDS WILL ALSO INCREASE TO 15-20 KT ALONG THE W COAST OF THE YUCATAN PENINSULA DURING THE EVENINGS DUE TO LOCAL EFFECTS. A TROPICAL WAVE CURRENTLY ALONG 78W/79W WILL REACH THE YUCATAN PENINSULA BY LATE THU. ...CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... MODEL PREFERENCE: LATEST GFS BLENDED WITH PREVIOUS/OFFICIAL FORECAST. LATEST MWW3 BLENDED WITH PREVIOUS/OFFICIAL FORECAST MEDIUM CONFIDENCE. A TROPICAL WAVE IN THE CENTRAL CARIBBEAN ALONG 78W/79W WILL MOVE INTO THE WESTERN CARIBBEAN TODAY THEN INTO THE YUCATAN PENINSULA LATE THU. THE NEXT TROPICAL WAVE IS ALONG 37W/38W. ALTHOUGH GLOBAL MODELS SHOWED SOME POTENTIAL FOR DEVELOPMENT AND IMPROVED ORGANIZATION OF THIS WAVE IN THE MEDIUM RANGE...ENVIRONMENTAL CONDITIONS REMAIN UNFAVORABLE FOR TROPICAL CYCLONE FORMATION. THE SYSTEM IS MOVING THROUGH A DRY AND STABLE ATMOSPHERE OVER MARGINALLY WARM WATERS. THUS A WELL DEFINED WAVE IS EXPECTED TO CONTINUE WWD AND REACH THE TROPICAL N ATLC WATERS EARLY ON FRI...THEN CROSS THE LESSER ANTILLES EARLY SAT. MARINE GUIDANCE SUGGESTS WIND OF 15-20 KT AND SEAS TO 8 FT IN ASSOCIATION WITH THIS WAVE. OTHERWISE...FRESH TO LOCALLY STRONG TRADES ARE NOTED OVER THE SOUTH-CENTRAL CARIBBEAN PER THE MOST RECENT SCATTEROMETER PASS WITH SEAS TO 8 FT NEAR THE COAST OF COLOMBIA BASED ON AN ALTIMETER PASS AND FEW SHIP OBSERVATIONS. THE PRES GRADIENT WILL TIGHTEN OVER THE CENTRAL CARIBBEAN WITH FRESH TO STRONG EASTERLY TRADES RETURNING TONIGHT...INCREASING EACH EVENING OFF THE NW COAST OF COLOMBIA. EXPECT BUILDING SEAS OF 8-12 FT AFFECTING MOST OF THE CENTRAL CARIBBEAN THU THROUGH SAT...AS WINDS INCREASE TO 25-30 KT NEAR THE COAST OF COLOMBIA BETWEEN 0000 AND 1200 UTC. ...SW N ATLANTIC INCLUDING THE BAHAMAS... MODEL PREFERENCE: LATEST GFS BLENDED WITH PREVIOUS/OFFICIAL FORECAST. LATEST MWW3 BLENDED WITH PREVIOUS/OFFICIAL FORECAST MEDIUM CONFIDENCE. A RIDGE EXTENDS FROM A 1023 MB HIGH PRES LOCATED NEAR 28N56W TO SOUTH FLORIDA. LIGHT TO GENTLE WINDS ARE NOTED ALONG THE RIDGE AXIS WITH SEAS OF 2-3 FT. S OF THE RIDGE...GENTLE TO MODERATE EASTERLY TRADES ARE OBSERVED WITH AN AREA OF 15-20 KT WINDS FROM N COAST OF HISPANIOLA THROUGH SRN BAHAMAS. N OF THE RIDGE...SWLY FLOW HAS INCREASED TO 15-20 KT AND LOCALLY 20-25 KT ACROSS WATERS N OF 30N BETWEEN 73W AND 79W. THESE WINDS ARE BLOWING AHEAD OF A FRONTAL BOUNDARY CURRENTLY EXTENDING OVER THE SE CONUS. MODELS FORECASTING LOW PRES ASSOCIATED WITH FRONT TO DEEPEN OFF NEW ENGLAND COAST TODAY AND THU AND ENHANCE THE PRES GRADIENT TO ITS S. AS A RESULT...EXPECT FRESH TO LOCALLY STRONG SW WINDS ACROSS THE FAR N WATERS TODAY AND TONIGHT WITH THESE CONDITIONS SHIFTING E OF 65W ON THU. THE RIDGE WILL SHIFT SLIGHTLY WWD DURING THAT TIME AND TIGHTEN PRES GRADIENT ACROSS THE CARIBBEAN...AND ACROSS SE WATERS AND INTO SE BAHAMAS AS WELL. THIS ALSO COINCIDES WITH TROPICAL WAVE ARRIVAL IN E CARIBBEAN WITH WAVE ACTING TO PRODUCE WIND SURGE THROUGH S AND SE ZONES AS IT MOVES THROUGH THE AREA DURING THE WEEKEND. TRADES OF 20-25 KT AND SEAS OF 6-8 FT ARE EXPECTED TO ACCOMPANY THIS WIND SURGE THROUGH THE AREA. $$ .WARNINGS...ANY CHANGES IMPACTING COASTAL NWS OFFICES WILL BE COORDINATED THROUGH AWIPS 12 PLANET CHAT OR BY TELEPHONE: .GULF OF MEXICO... NONE. .CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... NONE. .SW N ATLANTIC INCLUDING THE BAHAMAS... NONE. $$ *FOR DETAILED ZONE DESCRIPTIONS PLEASE VISIT: HTTP://WWW.NHC.NOAA.GOV/ABOUTTAFBPROD.SHTML#OWF NOTE: GRIDDED MARINE FORECASTS ARE AVAILABLE IN THE NATIONAL DIGITAL FORECAST DATABASE (NDFD) AT: HTTP://WWW.NHC.NOAA.GOV/MARINE/GRIDS.PHP FOR ADDITIONAL INFORMATION PLEASE VISIT: HTTP://WWW.HURRICANE WARNINGS.GOV/MARINE $$ .FORECASTER GR. NATIONAL HURRICANE CENTER.