000 AXNT20 KNHC 181754 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1254 PM EST Tue Dec 18 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 1745 UTC. ...MONSOON TROUGH/ITCZ... The monsoon trough passes from N Liberia near 06N10W to 03N16W. The ITCZ continues from that point to 02N30W to 01N40W. A surface trough is from 11N southward between 41W-43W. The ITCZ resumes from 01N45W to the coast of Brazil near 00N49W. Scattered moderate convection is noted 140 nm southwest of N Liberia from 04N-03N between 12W- 19W, and further west from 11N to 02S between 26W- 40W. Numerous moderate convection is observed along the vicinity of the surface trough extending 100 to 180 nm on either side of the trough. GULF OF MEXICO... An upper level low over southern NM is progressing eastward today supporting diffluence across northwest Gulf of Mexico. Numerous showers associated to the upper low are observed stretching from central Mexico to Brownsville, Texas near 26N97W to 29N92W. Along the northern and eastern Gulf coast, a 1022 mb high is centered over S Mississippi near 30N89W. Broken to overcast clouds cover much of the basin with 10-15 kt anticyclonic winds. This upper level low is forecast to intensify as it moves E-NE from Texas to the Carolinas Wed through Thu night, dragging a strong cold front across the Gulf waters. Marine conditions are expected to rapidly deteriorate across the region Thu afternoon as the low deepens. Gale force winds are likely north of 25N across the central and northern Gulf Thu night and Fri. Seas will build to a maximum around 20 ft on Fri over the central Gulf. CARIBBEAN SEA... A 1015 mb surface low is centered off the coast of Honduras near 16N85W. A stationary front extends north from the low to central Cuba near 20N78W then continues into the west Atlantic. Scattered showers are within 90 nm on either side of the front. Scatterometer data depicts moderate to fresh trades across the Caribbean. However, strong to near-gale winds will pulse at night near the coast of Colombia. Gentle winds are between Hispaniola and Jamaica. A weakening stationary front extending from eastern Cuba to 16N85W will dissipate later today, then drift westward over the Yucatan peninsula tonight as a surface trough. Fresh to strong winds will continue across the south-central Caribbean through Sat, with the strongest winds near the coast of Colombia each night. A cold front associated with an intense low pressure system north of the area will enter the NW Caribbean Thu night. ATLANTIC OCEAN... A cold front extends across the west Atlantic from 31N57W to 27N62W. A stationary front extends from that point to eastern Bahamas into eastern Cuba near 27N62W. Scattered showers are noted within 90 nm on either side of the boundary. Scattered moderate isolated strong convection is within 90 nm on either side of the cold front mainly from 21N-26N between 54W-61W. Surface ridging prevails across the basin anchored by a 1024 mb high centered near 26N37W. The western portion of the stationary front will slowly drift northward Wed and Thu as an intense low pressure system develops over the southeast U.S.. Gale force winds are likely north of 27N east of Florida Thu night through Fri night both ahead and behind of a cold front associated with the low. Maximum seas will build to around 20 ft by Fri night west of 70W. For additional information please visit http://www.hurricanes.gov/marine $$ Torres