000 AXNT20 KNHC 210005 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 705 PM EST Tue Feb 20 2018 Tropical Weather Discussion for North America, Central America Gulf of Mexico, Caribbean Sea, northern sections of South America, and Atlantic Ocean to the African coast from the Equator to 32N. The following information is based on satellite imagery, weather observations, radar and meteorological analysis. Based on 1800 UTC surface analysis and satellite imagery through 2300 UTC. ...SPECIAL FEATURES... Caribbean Sea Gale Warning: A tight surface pressure gradient continues to exist, between comparatively higher surface pressures in the western Atlantic Ocean, and lower surface pressures in northern sections of South America. This pattern is supporting winds reaching gale-force strength from 11N to 13N between 73W and 77W, for this week. Wave heights within the area of gale-force winds will range from 10 feet to 15 feet. Please read the latest NHC High Seas Forecast under AWIPS/WMO headers MIAHSFAT2/FZNT02 KNHC for more details. ...MONSOON TROUGH/ITCZ... The monsoon trough axis extends from the coast of Africa near 07N11W southwestward to 00N24W. The ITCZ crosses the equator near 24W and remains south of the discussion area to the coast of Brazil. isolated moderate to locally strong rainshowers are from 08N southward between 40W and 53W. ...DISCUSSION... GULF OF MEXICO... Upper level SW wind flow is moving from southern Mexico, across Texas and Louisiana and the Gulf of Mexico that is from 93W westward. Broad upper level anticyclonic wind flow spans the rest of the area. A surface ridge extends from the NE corner of the Gulf of Mexico, southwestward, to the coast of Mexico near 21N97W. across the entire basin from the Atlantic. Surface high pressure will prevail across the forecast waters. Fresh return flow will prevail across most of the basin, except to strong winds through the Straits of Florida and across central sections of the Gulf. CARIBBEAN SEA... Please read the SPECIAL FEATURES section for details about the Gale Warning for the waters that are near the coast of Colombia. Rainshowers are possible, in areas of broken-to-overcast low level clouds, across the entire area. Isolated moderate rainshowers have been evident in the SE part of the Yucatan Peninsula of Mexico during the last few hours. Surface high pressure across the NW Atlantic Ocean will build S across the region through Wednesday, and then settle across the Bermuda area through the end of the week. Fresh to strong trade winds will prevail across the Caribbean Sea and the Tropical N Atlantic waters through Thursday, with nocturnal winds pulsing to gale-force off the coast of Colombia. High pressure will weaken by Saturday, with the winds and seas diminishing. ATLANTIC OCEAN... A cold front passes through 31N33W, to 24N40W and 21N53W. A dissipating cold front continues from 21N53W to 22N61W. Broken to overcast low level clouds and possible rainshowers are to the NW and N of the line that passes through 32N29W 23N40W 19N56W 19N70W. High pressure will prevail across the forecast waters. Gentle to moderate winds will prevail N of 25N with fresh to strong winds S of 25N through Thursday. NNE swell will move through waters E of 65W from Wednesday through Saturday. For additional information please visit http://www.hurricanes.gov/marine $$ MT