000 AXNT20 KNHC 171127 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 627 AM EST SAT DEC 17 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 0600 UTC surface analysis and satellite imagery through 1100 UTC. ...SPECIAL FEATURE... A strong cold front will cross the western Gulf of Mexico this weekend. High pressure behind the front will support gale force northerly winds over portions of the western Gulf of Mexico beginning Sunday morning. The gale will then become confined to the southwestern Gulf of Mexico by Sunday night. Please refer to the Atlantic high seas forecast under AWIPS/WMO headers MIAHSFAT2/FZNT02 KNHC for more details. ...ITCZ/MONSOON TROUGH... The monsoon trough crosses the coast of Western Africa near 06N10W and continues over the eastern Atlantic to near 04N15W, where the intertropical convergence zone axis continues to 02N30W to 02N40W to 01N50W. Scattered moderate convection is from 02S to 10N between 07W and 36W. ...DISCUSSION... GULF OF MEXICO... High pressure centered just east of the United States mid Atlantic coast has an axis that extends across northern Florida and to the southwestern Gulf of Mexico. This pattern supports moderate to fresh southerly winds over the north central and western Gulf, and gentle to moderate east to southeasterly winds over the remainder of the Gulf, except locally fresh to strong southerly winds briefly this morning over the northwest Gulf. The return flow pattern currently taking place will continue until a cold front crosses the northwestern Gulf beginning early Sunday. Gale force northerly winds are forecast to develop behind this cold front. Please see the special features section for more details on this gale. CARIBBEAN SEA... Low pressure embedded in the monsoon trough south of Panama supports scattered to isolated showers and thunderstorms across the southwest Caribbean west of 77W, including Panama, Costa Rica, Nicaragua and E Honduras. Strong high pressure emerging from the United States over the western Atlantic waters along with local geography over Colombia supports fresh to strong NE to E winds from 11N to 13N between 73W and 78W. This area of winds will amplify and expand northward and across the southwest and eastern Caribbean today through Sunday as the strong ridge continues to move east over the western Atlantic waters. Gentle to moderate NE to E flow continues to cover the NW Caribbean waters. ...HISPANIOLA... A surface trough over the region is bringing scattered showers to the area. This trough will persist over the area through today. Then, strong dry air subsidence from aloft will allow for some drying over the area tonight and Sunday. ATLANTIC OCEAN... An upper trough over the western Atlantic and a surface low over the north central Atlantic support a cold front that enters the area of discussion near 31N49W and extends to 25N63W where it transitions to a stationary front to 23N77W. Fresh to strong NE to E winds are north of this front to 27N. Isolated moderate convection is within 360 nm east of the front north of 26N. A surface trough extends from 23N66W to the Dominican Republic near 19N72W. Scattered showers are within 90 nm of either side of the trough axis. High pressure centered near the Azores dominates the remainder of the Central and Eastern Atlantic. Over the next 24 hours the stationary front will dissipate while the cold front continues east. For additional information please visit http://www.hurricanes.gov/marine $$ Latto