000 AXNT20 KNHC 311756 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 156 PM EDT Wed Oct 31 2018 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 1200 UTC surface analysis and satellite imagery through 1715 UTC. ...SPECIAL FEATURES... Hurricane Oscar is centered near 36.6N 51.6W at 31/1500 UTC or 610 nm S of Cape Race Newfoundland moving NE at 25 kt. Estimated minimum central pressure is 979 mb. Maximum sustained wind speed is 65 kt with gusts to 80 kt. Numerous moderate convection extends in the northern semicircle out to 210 nm from the center. A faster motion toward the northeast or north-northeast over the north Atlantic Ocean is expected during the next couple of days. Oscar is expected to become an extratropical low over the north- central Atlantic Ocean later today. Oscar will remain a powerful post-tropical cyclone over the north-central and northeastern Atlantic Ocean into the weekend. See the latest NHC forecast/advisory under AWIPS/WMO headers MIATCPAT1/WTNT31 KNHC for more details. ...Strong Gulf of Mexico Cold Front... A cold front will move off the Texas coast into the NW Gulf of Mexico by early Thursday and continue moving southeast through the basin. A pre-frontal squall line with strong thunderstorms is likely within 180 nm ahead of the front over the northern Gulf, mainly north of 27N. The squall line should enter the NW Gulf from the Texas coast by late tonight and travel quickly eastward through the northern Gulf into Thursday evening. Brief gale force winds are possible in the squalls, with seas ranging between 6-9 ft. Refer to the Offshore Waters Forecast under AWIPS/WMO headers OFFNT4/FZNT4 KNHC for more details. ...TROPICAL WAVES... A tropical wave extends its axis along 47/48W from 01N to 12N, moving west at 10-15 kt. Model guidance shows a 700 mb trough to the east of the wave. TPW imagery depicts moderate to high moisture content near and east of the wave axis. Scattered moderate convection extends 90 nm on either side of the wave from 05N to 08N. A tropical wave extends its axis along 19W from 01N to 12N. This wave is noted in model guidance at 700 mb and TPW imagery show high moisture content associated with this wave. Scattered moderate convection extends south of 12N between 14W to 23W. Tropical wave that was along 59W has dissipated and has been removed from the analysis. ...MONSOON TROUGH/ITCZ... The monsoon trough is analyzed from 12N16W to 05N25W. The ITCZ extends from 05N26W to 07N45W, then resumes 07N50W to 06N57W. Aside from the convection related to the two tropical waves, isolated moderate convection is within 150 nm on either side of the ITCZ between 26W-38W. GULF OF MEXICO... A 1024 mb high pressure centered over the coast of North Carolina extends a ridge across the eastern and central Gulf of Mexico. Scattered showers and thunderstorms are observed over the northwest Gulf of Mexico north of 28N and west of 92W, extending along the Texas and western Louisiana coast. This activity will increase into late this afternoon as a squall line develops ahead of the cold front mentioned above in the Special Features section. A weak trough is noted over the Bay of Campeche near 20N93W. No significant convection is seen with this trough. Winds and seas will begin to increase across the Gulf tonight as return flow sets up across the western half of the Gulf ahead of a strong cold front expected to move off the Texas coast by early Thu with strong S to SW wind flow ahead of it, and gale-force wind gusts. The front will reach from the mouth of the Mississippi River to near Veracruz, Mexico Thu evening, from near Tampa Bay to the central Yucatan Peninsula Fri evening, then stall across the Straits of Florida to Cancun, Mexico Sat morning before drifting NW through Sun. For more information in regards to this feature, see the Special Features section above. CARIBBEAN SEA... A stationary front extends from the west Atlantic to eastern Cuba. Scattered showers are noted in the vicinity of Jamaica, Hispaniola and along the Windward Passage. In the far southwest Caribbean, scattered moderate to isolated strong convection is south of 11N near NW Colombia and the coast of Panama due to the monsoon trough proximity. Strengthening high pressure over the western Atlantic through Thu afternoon will act to freshen the tradewinds across the central Caribbean. The high will then continue to shift ENE through the weekend to produce fresh to strong tradewinds across the Caribbean east of 80W, especially the south-central Caribbean. These winds will be strongest at night close to the coast of Colombia. A Gulf of Mexico cold front will move SE to the Yucatan Channel and far NW Caribbean Sat morning and stall, then drift NW and back into the Gulf late Sat and Sun. ATLANTIC OCEAN... A cold front enters the area near 32N54W extends to 28N60W to 23N79W. To the east, a second cold front extends from 30N52W to 25N60W to 22N68W, then becomes stationary to eastern Cuba. These fronts are located southwest of Hurricane Oscar. A surface trough extends from 28N50W to 21N64W. Scattered showers are observed from the north coast of Dominican Republic to 23N and between 62W-71W. Scattered moderate convection is also present from 24N-31N between 44W and 53W. Large north swell will affect the waters north of 28N east of 25W through early Thursday. The two frontal boundaries from the central Atlc to the southern Bahamas will become aligned E to W and merge along 20N-21N by Fri evening as strong high pressure to the N shifts eastward along 33N. Moderate swell associated with exiting Oscar over the central Atlc will affect waters E of the Bahamas through Thu. Another cold front will move offshore of N Florida early Sat with strong southerly flow ahead of it Fri. The front is expected to weaken and stall from near 31N73W to the Florida Keys Sat evening before shifting NW Sat night through Sun. For additional information please visit http://www.hurricanes.gov/marine $$ MTorres/ABH