000 AGXX40 KNHC 271958 MIMATS Marine Weather Discussion NWS National Hurricane Center Miami FL 100 PM EDT Thu Jul 27 2017 Marine Weather Discussion for the Gulf of Mexico, Caribbean Sea, and Tropical North Atlantic from 07N to 19N between 55W and 64W and the Southwest North Atlantic including the Bahamas ...GULF OF MEXICO... A surface high will develop intermittently over the NW gulf waters along a surface ridge extending NW from SW Florida to the Texas Coastal Bend. Little change expected through Sat night, then the ridge will weaken and retract Eastward. A series of weak troughs are forecast to move slowly E across the NE gulf waters well to the N of the ridge. The current trough is accompanied by SCT TS, which will be depicted in the weather grids today. A more significant trough, or perhaps a weak cold front, will move off the Mississippi Delta on Sat night accompanied by a moderate SW-W-NW wind shift. This front will stall from the Florida Big Bend to 26N92W to the Texas Coastal Bend late Sun night. Blending global models leads to a solution of a weak surface low developing along the front over the NE gulf late Sun night, with low and frontal remnants drifting W on Tue as the ridge strengthens and rebuilds westward. Further S...a thermal trough will develop over the Yucatan Peninsula each evening before pushing offshore into the SW Gulf each night. The trough will drift westward during the overnight hours, and dissipate over the SW Gulf each morning. A moderate to locally fresh NE-E-SE wind shift is forecast along the trough, with seas of 2-4 ft. ...CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... Ridging N of the area continues to support fresh to locally strong trade across the Caribbean to the S of 17N and E of 82W, with the strongest winds along the coasts of NW Venezuela and Northern Colombia, with the area of strong winds extending as far N as 15N just prior to sunrise each morning. May see strong e winds along s coast of Hispaniola on Tue night. Moderate to locally fresh trades forecast across the waters E of the Lesser Antilles through Mon, with guidance suggesting that seas will build to 8 ft E of the Leewards on Mon night behind a tropical wave, with these sea conditions reaching the NE passages on Tue night. ...SW N ATLANTIC INCLUDING THE BAHAMAS... An E to W ridge extending from 31N55W to Port Canaveral Florida will shift S to a position from 30N54W to Port of Miami Florida on Sat, from 30N55W to 23N80W on Mon, then shift back N from 29N55W to Fort Pierce Florida early Wed. Moderate to locally fresh southerly flow will develop W of 77W and N of the ridge on Fri, and continue through Sat ahead of a weak cold front slipping off the Se Georgia coast late Sat night. The front will stall from 31N76W to 29N81W on Mon, drift W on Tue, and move inland the SE CONUS on Tue night. Moderate to locally fresh easterly flow is forecast S of the ridge, except becoming strong during the late afternoons and evenings along the N coast of Hispaniola, including the AtlC approach to the Windward Passage, beginning on Mon afternoon. Further E, the northern extent of a tropical wave will pass W through the tropical waters S of 22N, beginning with zone AMZ127 late Mon night and reaching zone AMZ125 on Tue night accompanied by fresh E winds and seas to 8 ft. $$ .WARNINGS...Any changes impacting coastal NWS offices will be coordinated through AWIPS II Collaboration Chat, or by telephone: .GULF OF MEXICO... None. .CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... None. .SW N ATLANTIC INCLUDING THE BAHAMAS... None. $$ *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.nhc.noaa.gov/marine $$ .Forecaster Nelson. National Hurricane Center. AGXX40 KNHC 121045 CCA MIMATS Marine Weather Discussion...CORRECTED NWS National Hurricane Center Miami FL 545 AM EST Sun Feb 12 2017 Marine Weather Discussion for the Gulf of Mexico, Caribbean Sea, and Tropical North Atlantic from 07N to 19N between 55W and 64W and the Southwest North Atlantic including the Bahamas ...GULF OF MEXICO...updated MODEL PREFERENCE: Global model consensus. High Confidence. High pressure prevails over the forecast waters. Latest buoy and platform observations along with Ascat data from last night show mainly gentle to moderate return flow across the waters. In the western portion, return flow is reaching the fresh category at times. Seas are in the 4-5 ft range, except for lower seas of 2-3 ft in the northeast portion and in the eastern Bay of Campeche. The high pressure ridge will shift southward through Monday allowing for a fairly weak cold front to drop southward over the northern waters. Northerly flow will be in the moderate range over those waters through Monday evening before diminishing to mostly a gentle northeast flow. The ridge will then retreat eastward as low pressure with an associated cold front moves across eastern Texas on Tuesday. The cold front will move over the northwest waters Tuesday night into Wednesday. The front will reach from the Florida panhandle to the Bay of Campeche Wednesday evening, and move southeast of the area on Thursday. Fresh to strong northwest to north winds will follow in behind the front, with near gale winds over the far southwest Gulf Wednesday. These winds will quickly diminish on Thursday as high pressure settles in over the area. Seas will subside throughout the basin on Thursday. Areas of dense fog observed last night across portions of the northwest gulf appear to have fractured into patches of dense fog. Latest fog guidance indicates that the fog should dissipate for the most part around or shortly after 15Z this morning. The fog may develop again tonight, and on Monday night. ...CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... MODEL PREFERENCE: Global model consensus. High Confidence. High pressure is centered north of the area. Latest satellite derived winds...buoy and ship observations reveal strong to near gale winds over the south central Caribbean, with the exception of a small area of minimal gale force northeast to east winds near the coast of Colombia. The observations show fresh to strong winds over the north central Caribbean, fresh winds over the eastern Caribbean, and moderate to fresh winds over the western Caribbean as well as over the tropical north Atlantic waters. Seas are in the 8-12 ft range over the south central Caribbean, except for higher seas of 10-14 ft in the area of gale force winds. Seas are 6-8 ft in the north central Caribbean, 4-6 ft in the eastern Caribbean, 5-6 ft in the western Caribbean, and 6-8 ft over the tropical north Atlantic waters south of 15N due to decaying NE to E swell there. A newly arrived set of NW swell has infiltrated the northern portion of the tropical north Atlantic bringing seas of 8-12 ft there, with the highest of the seas presently concentrated in the northwest part of zone AMZ127. This set of NW swell is indicated by wave model guidance to propagate southeastward through the remainder of the tropical north Atlantic into Monday while decaying. Seas will respond by lowering to 7-9 ft early on Monday, to 6-8 ft Monday afternoon, and to 5-7 ft Tuesday. Yet another set of NW swell is expected to impact the northern portion of tropical north Atlantic on Wednesday building seas to the range of 8-11 ft there. This set of swell, like the previous one, will also affect the remainder of the tropical north Atlantic zones on Thursday, but will be losing energy with seas lowering to 7-9 ft at that time. High pressure north of the area will weaken through Tuesday as it slides eastward. This will decrease winds and seas over the Caribbean waters, with winds and seas expected to fall below advisory criteria by late Tuesday. The gale conditions presently occurring near the coast of Colombia are forecast to diminish at or just past 12Z this morning. These winds will pulse back up to gale force one more time in the same geographic location tonight, but within a smaller coverage area. The winds then diminish early Monday morning. ...SW N ATLANTIC INCLUDING THE BAHAMAS... MODEL PREFERENCE: Global model consensus. High Confidence. High pressure prevails over the forecast area. A dissipating stationary front prevails over the southeast waters. Latest satellite derived winds along with ship...buoy...and CMAN data depict fresh to strong northeast winds over the southern waters and light to gentle winds over the northern waters. The fresh to strong northeast winds were confirmed by the 0134Z Ascat pass from last night as well. Seas are in the 8-11 ft south of 26N and east of the Bahamas, and 6-9 ft elsewhere to the east and northeast of the Bahamas. Seas elsewhere are in the 4-6 ft range, except for lower seas of 1-3 ft west of the Bahamas. The front will lose its identity today possibly transitioning to a shear line feature. Global models have been consistently suggesting that a series of cold fronts will move across the northern waters during the forecast period attendant by strong winds east and west of them. In addition, the fronts will be followed by sets of long period NW to N swell that will affect the waters east of the Bahamas during the period. The swell could potentially create hazardous marine conditions for vessels navigating those waters. Max seas are expected to peak to around 19 ft in the far northeast portion of the area on Tuesday before subsiding to 10 ft on Wednesday. Seas will peak to around 14 ft in zone AMZ113 on Thursday in the next round of long period NW to N swell. $$ .WARNINGS...Any changes impacting coastal NWS offices will be coordinated through AWIPS II Collaboration Chat, or by telephone: .GULF OF MEXICO... None. .CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... .AMZ031...CARIBBEAN FROM 11N TO 15N BETWEEN 72W AND 80W INCLUDING COLOMBIA BASIN... Gale Warning through 12Z this morning. Gale Warning tonight. .SW N ATLANTIC INCLUDING THE BAHAMAS... None. $$ *For detailed zone descriptions, please visit: http://www.nhc.noaa.gov/abouttafbprod.shtml#OWF Note: gridded marine forecasts are available in the National Digital Forecast Database (NDFD) at: http://www.nhc.noaa.gov/marine/grids.php For additional information, please visit: http://www.nhc.noaa.gov/marine $$ .Forecaster Aguirre. National Hurricane Center.