000 AXNT20 KNHC 042305 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 605 PM EST SUN DEC 4 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 2230 UTC. ...SPECIAL FEATURES... Very broad middle to upper level troughing is noted on water vapor imagery over the central North Atlc waters supporting a cold front analyzed from 32N41W SW to near the SE Bahamas. The front is generating near gale to gale force SW winds N of 30N east of the front to 39W. The near gale to gale force conditions are expected to persist through late Monday. See latest NWS High Seas Forecast under AWIPS/WMO headers MIAHSFAT2/FZNT02 KNHC for more details. ...ITCZ/MONSOON TROUGH... The Monsoon Trough extends from the African coast near 06N10W to 04N14W to 05N18W. The Intertropical Convergence Zone axis extends from 05N18W to 06N24W to 04N35W to 05N41W. Widely scattered moderate convection is from 04N-08N between 06W-12W...and from the Equator to 03N between 30W-39W. ...DISCUSSION... GULF OF MEXICO... Southwesterly flow aloft prevails ahead of an approaching upper level trough and vigorous middle level low noted on water vapor imagery over northern Mexico and portions of western Texas. This upper level feature is continuing to support a developing and complex area of lower pressure across northern Mexico...the NW Gulf and north-central Gulf waters. A stationary front extends from a 1011 mb low centered near Mobile Bay SW into a 1010 mb low centered near 28N95W S-SW to the Mexico coast near 22N97W. Scattered to numerous showers and scattered tstms are occurring NW of a line from Mobile Bay near 30N88W to 24N96W...including interior portions of eastern Texas...Louisiana...Mississippi...and Alabama. Otherwise...a few widely scattered showers and tstms are occurring across the SE Gulf waters in association with low-level convergence and upper level diffluence S of 24N between 82W-88W. Generally gentle to moderate SE winds are anticipated SE of the front through Monday with fresh to occasional strong N-NE winds expected N and W of the front. The front is expected to remain relatively stationary through Monday morning. Thereafter... cyclogenesis is expected to occur across the NW Gulf waters in the vicinity of Corpus Christi Texas with the associated cold front emerging off the Texas coast by afternoon. The front will quickly move across the basin through Tuesday night into Wednesday and stall across the central Florida peninsula and SE Gulf waters. CARIBBEAN SEA... An upper level ridge remains centered over the SW Caribbean influencing much of the basin with axis extending from 11N82W to 23N80W. Water vapor imagery indicates relatively dry and stable air aloft in association with the ridging however low-level moisture convergence along with a favorable middle to upper level diffluent environment is providing focus for scattered showers and widely scattered tstms within 180 nm either side of a line from 12N78W to the western Yucatan Channel region near 22N85W. Isolated showers and tstms are also occurring across portions of Central America S of 13N due to the close proximity of the Monsoon Trough axis along 09N/10N. Otherwise...moderate to fresh trades prevail and are expected to persist through Tuesday. ...HISPANIOLA... Currently isolated showers linger across the island and the adjacent Caribbean Sea waters. This generally lower level moisture and cloudiness remains beneath an upper level ridge anchored over the SW Caribbean Sea near 11N82W. Water vapor imagery indicates a relatively dry and stable environment persists aloft. ATLANTIC OCEAN... Generally W-NW flow aloft prevails to 50W...with the special features cold front extending into the discussion area near 32N41W SW to the SE Bahamas near 23N73W. Widely scattered showers and isolated tstms are noted within 120 nm either side of the front E of 50W...and within 75 nm either side of the front W of 50W. To the SE...a surface trough is analyzed from Puerto Rico NE to the cold front near 26N54W. Within a weakness between ridging across the central Atlc and the SW North Atlc...isolated showers and tstms are occurring within 150 nm either side of the boundary. Otherwise...the remainder of the eastern and central Atlc is under the influence of a surface ridge anchored by a 1017 mb high centered near 23N31W. Within the southwestern periphery of the ridge...an upper level trough axis extends from 23N41W to a broad base in the deep tropics near 14N49W. Southwesterly flow aloft is generating a large area of cloudiness and precipitation extends from 06N-23N between 30W-47W. A surface trough analyzed from 10N47W to 20N44W is providing low-level focus for the more intense convection in the vicinity of 12N45W. For additional information please visit http://www.hurricanes.gov/marine $$ HUFFMAN