000 AGXX40 KNHC 231910 MIMATS Marine Weather Discussion NWS National Hurricane Center Miami FL 310 PM EDT Fri Mar 23 2018 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... Latest observations indicate moderate to fresh return flow across the basin around 1028 mb high pressure located over southern Georgia. Seas are 4 to 6 ft, except 2 to 4 ft in the NE Gulf. The high will linger through early Sat, then will shift eastward into the Atlantic. The pressure gradient will tighten in the W central and NW Gulf Sat afternoon and night, increasing return flow to fresh to strong temporarily in those areas with seas building to near 8 ft. The local gradient will relax there by Sun afternoon, with moderate to fresh SE to S flow across the western half of the Gulf and moderate E to SE flow across the eastern half through the end of the weekend. Stronger high pressure will build down NE of the area from the Carolinas by early next week increasing E to SE winds to fresh to strong across the basin. These conditions will persist through Wed. A cold front may move into the NW Gulf coastal waters by Wed night, but may have trouble progressing eastward as high pressure ridging attempts to hold firm. ...CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... High pressure NE of the area will continue to induce moderate to fresh trades across the basin for the next several days. One exception will be NW of the coast of Colombia where locally deep low pressure will reside creating a locally tight pressure gradient. This will allow for pulsing minimal gale force winds in the area each night through much of next week. Also, winds will pulse to fresh to strong across the approach to the Windward Passage and in the lee of eastern Cuba through early Sun, then in the lee of Hispaniola early Sun through Wed night. Undersea volcano Kick em Jenny, N of Grenada near 12.18N 61.38W, is in a state of unrest. The government of Grenada advises mariners to observe a 5 km or 3.1 nm exclusion zone around Kick em Jenny. Please see www.nadma.gd for additional information. ...SW N ATLANTIC INCLUDING THE BAHAMAS... A weakening cold front from 26N65W to the N coast of Haiti is stalling with a reinforcing trough extending from 31N68W to 28N73W. Mainly moderate to fresh winds are found on either side of the front, along with 5 to 8 ft seas in northerly swell, except 3 ft or less inside protected ares SW of the Bahamas. A reinforcing cold front will clip the NE portion tonight through Sat afternoon with a brief surge of NW fresh to strong winds and building seas to 8 to 12 ft. Otherwise, high pressure will sink SE from the Carolinas. This high will exit eastward Sun as developing low pressure N of the area drags a front southward along 31N. SW to W winds S of this boundary will increase to fresh to near gale force with the cold front sinking southward to 27N by Mon afternoon, reaching along 22N by Tue morning, washing out and exiting to the SE thereafter. Strong high pressure will build behind the front, ushering in fresh to locally strong N to NE flow. Northerly swells will gradually build, approaching 8 to 15 ft across the basin by early Wed. $$ .WARNINGS...Any changes impacting coastal NWS offices will be coordinated through AWIPS II Collaboration Chat, or by telephone: .GULF OF MEXICO... None. .CARIBBEAN SEA AND TROPICAL N ATLANTIC FROM 07N TO 19N BETWEEN 55W AND 64W... .AMZ031...CARIBBEAN FROM 11N TO 15N BETWEEN 72W AND 80W INCLUDING COLOMBIA BASIN... Gale Warning tonight. Gale Warning Sat night. GALE CONDITIONS POSSIBLE Sun night. GALE CONDITIONS POSSIBLE Mon night. GALE CONDITIONS POSSIBLE Tue night. GALE CONDITIONS POSSIBLE Wed night. .SW N ATLANTIC INCLUDING THE BAHAMAS... None. $$ *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 Lewitsky. National Hurricane Center.