000 AXNT20 KNHC 010001 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 801 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 1800 UTC surface analysis and satellite imagery through 0000 UTC. ...SPECIAL FEATURES... Post-Tropical Cyclone Oscar centered near 39.3N 49.6W at 31/2100 UTC or 470 nm SSE of Cape Race Newfoundland moving NNE at 30 kt. Estimated minimum central pressure is 976 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 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 20W from 02N-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 and east of 20W. A tropical wave extends its axis along 49W 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. ...MONSOON TROUGH/ITCZ... The monsoon trough is analyzed from 12N16W to 05N26W. The ITCZ extends from 05N26W to 07N47W, then resumes near 07N52W to 06N57W. Aside from the convection related to the two tropical waves, scattered showers are within 150 nm on either side of the ITCZ between 26W-38W. GULF OF MEXICO... A 1023 mb high pressure centered over the northwest Atlantic extends across most of the basin. 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 evening as a squall line develops ahead of the cold front mentioned above in the Special Features section. 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 north-central Cuba. Scattered showers are noted in the vicinity of Jamaica, Hispaniola and along the Windward Passage in the vicinity of a surface trough that extends to the north of Hispaniola. In the far southwest Caribbean, scattered moderate 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 31N51W extends to 24N75W. A surface trough extends from 29N48W to 21N70W. Scattered showers are observed along and within 105 nm on either side of the trough. Large north swell will affect the waters north of 28N east of 25W through early Thursday. The cold front will continue moving east while weakening. Strong high pressure to the N will shift 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 $$ AH/ERA