000 AXNT20 KNHC 290605 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 105 AM EST Wed Nov 29 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 0000 UTC surface analysis and satellite imagery through 0545 UTC. ...ITCZ/MONSOON TROUGH... The monsoon trough extends from the African coast near 09N13W to 09N20W. The Intertropical Convergence Zone extends from 09N20W to 05N36W to 02N51W. Scattered moderate convection is from 06N-15N between 16W-28W and from 02S-08N between 26W-38W. ...DISCUSSION... GULF OF MEXICO... A broad middle level low and associated trough covers much of the Gulf and continue to support a surface trough from 27N92W SE to the Yucatan Channel near 21N85W to NE Nicaragua adjacent waters near 14N81W. GOES-16 water vapor imagery show deep layer dry air across most of the Gulf, except a portion of the SE Gulf where shallow moisture supports isolated showers and tstms S of 26N E of 88W, including the Florida Straits. Otherwise, surface ridging prevails elsewhere, thus providing moderate to fresh E winds in the SE Gulf near the trough and light to gentle variable winds across the remainder basin. The trough will remain stationary the next two days ahead of the next cold front forecast to move off the Texas and Louisiana coasts Thursday morning. The front will then move to the north-central Gulf waters Friday morning before stalling. CARIBBEAN SEA... A middle level low centered in the Gulf of Mexico extends a trough SE to W Caribbean waters where it continues to support a surface trough extending from the Yucatan Channel near 21N85W to NE Nicaragua adjacent waters near 14N81W. The trough along with diffluent flow aloft support scattered showers and tstms N of 19N between 80W and 84W. Isolated showers are W of the trough in the Gulf of Honduras and within 120 nm either side of the trough axis. In the SW basin, a 1008 mb low embedded in the eastern extension of the EPAC monsoon trough support scattered scattered showers and isolated tstms S of 14N between 78W and 83W. Strong high pressure N of the area support moderate to fresh NNW winds W of the surface trough and in the south-central Caribbean. Moderate trades dominate elsewhere. The surface trough will dissipate Wednesday night off the Yucatan Peninsula. Otherwise, as high pressure continues to move off the eastern CONUS, trades across the south-central Caribbean will increase briefly into strong to near gale-force levels today...weakening again on Thursday. ...HISPANIOLA... Generally clear skies and fair weather conditions are across the island as the influence of mid to upper-level ridging remains in place over the region. Increasing cloudiness is expected today as the ridge slides eastward and southwesterly flow aloft begins to influence the region. ATLANTIC OCEAN... A mid to upper-level low and associated troughing are noted on water vapor imagery over the western Atlantic supporting a weak surface trough from 30N48W to 26N65W. A shearline extends from the trough tail to the central Bahamas near 24N75W. Scattered moderate convection is noted along this boundary mainly north of 25N between 66W-76W. To the east, another surface trough extends from 29N33W to 25N37W with no significant convection. The remainder of the basin is under the influence of a surface ridge, anchored by a 1020 mb high near 23N37W and a 1021 mb high near 24N46W. Surface troughing will prevail in the SW N Atlc while a new cold front enters the north-central Atlc waters. For additional information please visit http://www.hurricanes.gov/marine $$ Ramos