000 AXNT20 KNHC 072349 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 649 PM EST Thu Dec 7 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 1800 UTC surface analysis and satellite imagery through 2345 UTC. ...SPECIAL FEATURES... ...GALE-FORCE WINDS IN THE GULF OF MEXICO... A stationary front extends from the Tampa Bay area of Florida to 26N87W then through a 1013 mb low centered near 24N94W to 18N94W. A strong pressure gradient is noted across the northern Gulf of Mexico as another low is centered over southern Texas interacting with a high pressure area that prevails over eastern US. With this, gale-force winds have developed north of 21N and west of 93W. These conditions will spread to the southwest Gulf this evening and through Friday morning as a reinforcing push of cooler and drier air moves into the region. Wave heights will peak to 14 ft. Please read the latest NWS High Seas Forecast under AWIPS/WMO headers MIAHSFAT2/FZNT02 for more details. ...ITCZ/MONSOON TROUGH... The monsoon trough extends across the Africa coast near 11N15W and extends to the east Atlantic near 07N20W. The Intertropical Convergence Zone extends from 07N20W to 03N46W. A surface trough extends from 09N41W to 07N41W. Scattered moderate convection is noted along and within 300 nm north of these boundaries between 20W-42W. ...DISCUSSION... GULF OF MEXICO... A stationary front extends from the Tampa Bay area of Florida to 26N87W then through a 1013 mb low centered near 24N94W to 18N94W. Gale force winds have developed to the north and west of these features. Please refer to the section above for details. Scatterometer data depicts gentle to moderate winds to the south and east of the front/low. Expect for the low to move east- northeast through the next 24 hours. Thereafter, the upper-level trough supporting the frontal system will dig farther south, and allow the low to accelerate NE and bring its cold front across the remainder of the basin. CARIBBEAN SEA... Deep moisture over the west Caribbean is interacting with a diffluent flow aloft and a surface trough to support scattered moderate convection west of 80W. This activity is impacting Honduras, Nicaragua, and the Cayman Islands. To the southwest, the monsoon trough extends along 10N enhancing convection over Costa Rica, Panama, and adjacent waters between 78W-83W. To the east, the tail end of a dissipating stationary front extends from the central Atlantic to the Lesser Antilles near 16N61W to 16N66W. Isolated showers prevail along this boundary. Generally fair weather covers the remainder of the basin, with scatterometer data depicting moderate to strong trades across the area. Expect for a frontal boundary to enter the northwest Caribbean during the next 48 hours with strong to near gale-force winds mainly behind the front. ...HISPANIOLA... Fair weather prevails across the island as a surface high centered over the central Atlantic extends through the area. Isolated convection could develop in the afternoon hours through the weekend due to daytime heating. ATLANTIC OCEAN... A stationary front extends across the west Atlantic from 31N76W to 28N81W. To the southeast, a surface trough is from 31N75W to 27N80W. Isolated showers are noted along these boundaries. To the east, a 1023 mb surface high is centered near 29N60W. A cold front extends across the east Atlantic from 31N33W to 19N42W to 15N58W, then becomes weak and stationary to 16N61W. Scattered moderate convection is north of 24N between 31W-34W. A surface ridge prevails elsewhere with fair weather. During the next 24 hours, the frontal boundary over the west Atlantic will push southeast through Saturday. A new low pressure area will develop under the upper-level low in the central Atlantic and will move southwest over our area of discussion enhancing convection. For additional information please visit http://www.hurricanes.gov/marine $$ ERA