000 AXNT20 KNHC 291719 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1218 PM EST THU DEC 29 2016 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... ...Gulf of Mexico Gale Warning... A cold front is already moving across the northwest Gulf of Mexico a of 1500 UTC. As the front moves through the basin, a surface ridge will build in the wake of the front. The pressure gradient generated in the area will support gale-force winds south of 24N west of 96W from this afternoon through the next 36 hours. Please see the High Seas Forecast under AWIPS/WMO headers MIAHSFAT2/FZNT02 KNHC for more details. ...ITCZ/MONSOON TROUGH... The Monsoon Trough extends across Africa reaching the east Atlantic near 04N09W to 03N01W. The ITCZ begins from that point to 04N17W to 02N40W. Isolated showers are observed along these boundaries. ...DISCUSSION... GULF OF MEXICO... A Gale Warning is in effect for the southwest Gulf. Please refer to the section above for details. A cold front is currently moving across the northwest Gulf enhancing winds/seas. Over the remainder of the basin, a 1019 surface high is centered near 26N82W and extends its ridge across the whole area. Scatterometer data depicts a light to gentle anticyclonic flow across the basin. The front will quickly move over the central and eastern Gulf through early Friday. High pressure in the wake of the front will shift eastward along 31N through Saturday night. CARIBBEAN SEA... The pressure gradient generated by the interaction of the surface high that prevails across the Atlantic and lower pressures across the northern portion of South America is supporting moderate to fresh trades across the Caribbean waters. Low-level moisture transported by the trades is generating isolated low-topped showers that will continue moving quickly across the basin. Winds will diminish later tonight through Friday night as the pressure gradient weakens. A cold front is expected to move into the northwest Caribbean by late Friday. The front will then stall from the Windward Passage to the Gulf of Honduras by Saturday night. HISPANIOLA... Fair weather prevails across the island at this time. Isolated showers are possible across the island through Friday due to daytime heating. Convection will increase by this weekend as a cold front approaches and stall over the Windward Passage by Saturday night. ATLANTIC OCEAN... A surface trough extends across the west Atlantic from 25N71W to 22N72W. Isolated showers are observed along this trough. A surface ridge extends across the central Atlantic anchored by a 1025 mb high centered near 29N51W. To the east, a surface trough extends from 21N31W to 32N23W with no significant convection. A cold front will move off the northeast Florida coast tonight reaching from Bermuda to central Cuba Friday evening and from 32N54W along 24N65W to the Windward Passage Saturday evening. Strong high pressure behind the front will shift eastward along 30N through Saturday night. For additional information please visit http://www.hurricanes.gov/marine $$ ERA