000 AXNT20 KNHC 252338 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 633 PM EST SUN DEC 25 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 and enters the east Tropical Atlantic through Liberia near 5N9W to 3N16W. The ITCZ continues from 3N16W to 6N30W to 6N40W to 4N51W. Scattered moderate to isolated strong convection is from 3N-4.5N between 12N-18N. Similar convection is from 2N-6N between 29W-37W. ...DISCUSSION... GULF OF MEXICO... A ridge extends from the SE CONUS to the SW Gulf producing mainly moderate to locally fresh E-SE winds. Mainly fresh winds are blowing across the SE Gulf. The ridge will prevail through Wednesday night. A trough will develop each night over the Yucatan peninsula and move W-NW into the SW Gulf each night, then dissipate over the SW Gulf by late morning. Shallow moisture embedded in a southerly return flow is noted across the western Gulf. The next cold front will move across the N-central and NE Gulf waters on Thursday. Aloft, a ridge is over the State of Florida with a southerly flow dominating the entire Gulf region. CARIBBEAN SEA... The most recent scatterometer data indicated fresh to strong winds across much of the east and central Caribbean with strong to near gale force winds near the coast of Colombia. Fresh to locally strong winds are also noted across the Windward Passage and the Yucatan Channel. These winds are the result of a tight pressure gradient between a strong high pressure N of area and the Colombian/Panamaniam low. Low-topped trade wind showers are moving across the east and central Caribbean. Convection increases across the regional waters of eastern Nicaragua and NE Honduras. A diffluent pattern aloft supports this convective activity. The high pressure N of area will continue to support fresh to strong winds across much of the Caribbean Sea through Tuesday, then diminish on Wednesday and Thursday as the ridge shifts east and weakens. HISPANIOLA... Shallow moisture embedded in the trade wind flow will move across the region producing isolated to scattered passing showers and gusty winds. This scenario will continue through mid-week. ATLANTIC OCEAN... Strong high pressure moving toward the NE of United States extends a ridge across the western Atlantic west of 60W. Moderate to strong winds are seen per scatterometer data along the southern periphery of the ridge, particularly between the Bahamas and Cuba. A frontal trough extends from 31N54W to 27N57W. Isolated showers are near the trough axis. The remainder of the Atlantic is under the influence of another ridge anchored by a 1033 mb high pressure located near 40N16W. An upper-level low is spinning between the Madeira and the Canary Islands generating some shower activity. The next cold front is forecast to enter the western Atlantic on Thursday night and reach from Bermuda to the central Bahamas on Friday. In the upper-levels, a ridge/trough/ridge pattern dominates the forecast region. For additional information please visit http://www.hurricanes.gov/marine $$ GR