000 AXNT20 KNHC 111701 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1201 PM EST Sun Feb 11 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 1200 UTC surface analysis and satellite imagery through 1700 UTC. ...SPECIAL FEATURES... Caribbean Sea Gale Warning: A tight surface pressure gradient between the strong surface ridge over the north Atlantic Ocean and lower pressures over northwestern South America will continue to support gale-force winds within 90 nm off the coast of Colombia. These conditions will continue through at least mid week. Please read the latest NHC High Seas Forecast under AWIPS/WMO headers MIAHSFAT2/FZNT02 KNHC for more details. ...MONSOON TROUGH/ITCZ... The monsoon trough enters the Atlantic through near 06N10W and continues to 00N20W. The ITCZ begins near 00N20W and extends to the coast of Brazil near 04S38W. Scattered showers are within 75 nm on either side of these boundaries between 18W-30W. ...DISCUSSION... GULF OF MEXICO... A cold front extends across the northwest Gulf waters from 30N93W to 27N97W. A pre-frontal trough has developed south of the Florida Panhandle extending from 30N88W to 28N90W. Scattered to numerous moderate convection prevails along the trough, while minimal convection is currently related to the front. Patchy fog has been reported in the vicinity of the front. Fresh northerly winds are expected north of the front while moderate southerly winds will prevail south of it. Over the remainder of the basin, a surface ridge extends from the north Atlantic through the east and central Gulf, supporting gentle to moderate southerly winds. The front will reach from southeast Louisiana to near Brownsville, Texas by tonight, and from the western Florida Panhandle to the western Bay of Campeche by Mon evening, where it will stall and weaken. Fresh to strong northerly winds and building seas to 8 ft will continue following the front tonight and Mon. Winds and seas will diminish by Tue as a ridge develops over the southeast United States. This pattern will support fresh east winds by mid week. CARIBBEAN SEA... Please refer to the SPECIAL FEATURES section above for details about the gale-force winds expected near the coast of Colombia. GOES-16 water vapor imagery continues to show deep layer stable, dry air across most of the basin, which is supporting generally fair weather conditions. Strong high pressure north of the area continues to support fresh to strong trade winds across the eastern and central Caribbean, as noted in latest scatterometer data. Seas are reaching 8 to 12 ft, except near the Colombia coast where seas will be up to 16 ft. The areal extent of the strong trade winds and associated seas will spread westward through mid week, including the Windward Passage and lee of Cuba. Otherwise, little change is expected. ATLANTIC OCEAN... Broad surface ridging anchored north of the area by a 1044 mb high near 42N39W extends across the basin. The ridge is supporting moderate to fresh east to southeast winds over most of the basin. A surface trough extends north of Hispaniola from 24N69W to 20N72W with scattered showers mainly over the souther portion of it. A cold front is expected to move off the northeast Florida coast by Tue afternoon, followed by fresh northerly flow and building seas north of the Bahamas, then diminish through mid week as the front stalls and dissipates. Over the eastern Atlantic, moderate to fresh northeast winds dominate this region, except for strong winds north of the Cape Verde islands. 8-10 ft seas could be expected in this area. These conditions will diminish during the next 24 hours. For additional information please visit http://www.hurricanes.gov/marine $$ ERA