000 AXNT20 KNHC 011819 RRA TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1213 PM EST SUN JAN 1 2017 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 1715 UTC. ...SPECIAL FEATURES... ...Caribbean Gale Warning... The nocturnal pressure gradient will tighten tonight and again Monday night between the surface ridge over the west Atlantic and the lower pressure over South America to support gale force winds across the south- central Caribbean mainly from 11N-13N between 73W-76W. Please see the High Seas Forecast product under AWIPS/WMO headers MIAHSFAT2/FZNT02 KNHC for more details. ...ITCZ/MONSOON TROUGH... The Monsoon Trough extends across southwest Africa into the east Tropical Atlantic near 10N14W to 06N22W where the ITCZ begins and continues along 04N30W to 04N40W to 01N50W. Scattered moderate convection is from 02N to 09N between 26W and 53W. ...DISCUSSION... GULF OF MEXICO... A high pressure ridge axis extends from western Atlantic high pressure across the Florida peninsula to the west-central Gulf of Mexico. This supports mainly fresh to strong southeast to south winds across the Gulf basin. An upper trough inland over the central United States is supporting a cold front along the Texas coast with a pair of surface low pressures inland over Texas and Mississippi. These features are supporting scattered showers and thunderstorms within 150 nm of the Texas and Louisiana coasts. A thermal surface trough along the Mexico Coast near Vera Cruz supports patchy fog and scattered showers. Over the next 24 hours the cold front along the Texas coast will dissipate, while fresh to strong return flow persists across the majority of the Gulf basin. CARIBBEAN SEA... Strong western Atlantic high pressure is supporting fresh to strong trades across the majority of the central and eastern Caribbean, with moderate to fresh trades over the northwestern Caribbean. A weak surface trough is over the north central Caribbean between Jamaica and Windward Passage supporting isolated showers. Tonight and again Monday night winds will pulse to gale- force along the northern coast of Colombia as the nocturnal pressure gradient tightens between lower pressures over Colombia and the high pressure to the north. Please see the special features section for more details. HISPANIOLA... Scattered showers will continue to occur over the windward locations of the island in the trade wind flow through at least Monday. ATLANTIC OCEAN... An upper trough over the central Atlantic supports a cold front that extends into our area of discussion near 31N43W to 27N49W then is stationary to 23N63W to 23N73W. Scattered showers are within 120 nm of either side of this front. Otherwise, a 1031 mb high centered near 34N57W dominates the remainder of the central and western Atlantic. Farther east, a weakening cold front extends from 31N24W to 28N31W and is then dissipating stationary to 29N39W. Scattered showers are within 120 nm south of the front. Over the next 24 hours the stationary front over the central and western Atlantic will dissipate as the high north of the region builds southward. For additional information please visit http://www.hurricanes.gov/marine $$ Latto