000 AXNT20 KNHC 262318 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 705 PM EST MON DEC 26 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 1800 UTC surface analysis and satellite imagery through 2315 UTC. ...ITCZ/MONSOON TROUGH... The Monsoon Trough extends across Africa with the ITCZ beginning at the coast near 5N10W and continues along 5N15W 4N21W to 5N35W. A surface trough extends from 9N38W to 5N40W. Clusters of scattered moderate convection are from 2N to the southwest coast of Africa between 1W-10W and from 1N-7N between 19W-28W. ...DISCUSSION... GULF OF MEXICO... An upper ridge extends from the east Pacific region across Mexico to south Texas covering the southwest Gulf while a second upper ridge extends from the Caribbean across east Cuba and into the west Atlantic covering the east Gulf. A shortwave upper trough is between these upper features extending from the Louisiana/Texas border the northwest Yucatan Peninsula. At the surface is a surface ridge covering the Gulf anchored by a 1034 mb high over southern Virginia. The easterly surface flow through the Straits of Florida is generating scattered showers and possible isolated thunderstorms from 23N-25N east of 86W. This easterly flow will weaken early Tuesday as the surface ridge shifts eastward. Warm, moist, easterly surface flow will support patchy fog over the northwest Gulf through early Tuesday. A cold front is expected to enter the Gulf on Thursday. CARIBBEAN SEA... An upper ridge extends from over South America across Colombia and the west Caribbean then over east Cuba into the west Atlantic. Difflunce on the west side of this upper ridge coupled with easterly trade winds are developing scattered to numerous showers and isolated thunderstorms over the west Caribbean southwest of a line from the Yucatan near 20N87W along 15N82W to Colombia near 10N76W including the Gulf of Honduras and Central America. Isolated showers are possible across the east Caribbean. The west Atlantic surface ridge is giving the Caribbean fresh to strong northeast winds that will continue through Tuesday. Winds will diminish Wednesday through the end of the week as the surface ridge weakens. HISPANIOLA... Isolated showers are possible across the Dominican Republic this evening due to the northeasterly trade winds. Fair weather is expected elsewhere. This scenario will continue through Thursday. ATLANTIC OCEAN... The upper ridge over the Caribbean extends across east Cuba over the west Atlantic. A surface ridge also covers the west Atlantic anchored by 1038 mb high over the Canadian Maritimes. An upper trough over the central Atlantic is supporting a cold front that extends through 32N45W to 31N48W. A surface trough extends from 31N45W to 27N53W. Isolated showers are within 120 nm east of the surface trough. A second surface ridge covers the east Atlantic east of 30W. The west Atlantic surface ridge will persist through Thursday night. A cold front will move off the northeast Florida coast Thursday night. For additional information please visit http://www.hurricanes.gov/marine $$ PAW