000 AXNT20 KNHC 072342 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 642 PM EST WED DEC 7 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 2330 UTC. ...SPECIAL FEATURES... A frontal system will enter the northern portion of the Gulf of Mexico tonight into early Thursday. Strong northerly winds will prevail behind the front with gusts to gale force affecting the area north of 25N and west of 90W. These conditions will continue through the end of the week. Please see the 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 07N12W to 05N16W. The Intertropical Convergence Zone extends from 05N16W to 04N29W to 01N44W. Scattered moderate convection is from 02N-05N between 32W-50W. A surface trough is analyzed W of the ITCZ from 17N57W to 08N57W. Scattered moderate convection is along this boundary between 52W-61W. ...DISCUSSION... GULF OF MEXICO... Gale force winds are expected to develop across the northern Gulf during the next 12-18 hours. Please refer to the section above for details. A dry stationary front extends from 26N97W to 29N90W to 30N84W. To the south, another stationary front extends from 21N96W to 25N81W. Isolated showers are observed along this boundary. Scatterometer data depicts gentle to moderate easterly winds across the basin, with some variations near the frontal boundaries. During the next 24 hours, a stronger cold front is expected to move off the Texas and Louisiana coast introducing the strong to gale force northeast winds mentioned above. For the remainder of the week, strong to near gale force northeast winds will prevail as the front moves southeast across the basin. CARIBBEAN SEA... Water vapor imagery indicates a mostly dry and stable environment aloft between an upper level anticyclone centered near 16N85W and a broad upper-level low centered near 13N68W. At the surface, mostly clear skies prevail across the basin except along the Monsoon Trough that extends along 09N between 78W-83W. A 1009 mb surface low is centered in the Monsoon Trough near 10N78W. Scattered moderate convection is observed with this low. Scatterometer data depicts trade winds generally in the moderate to fresh levels with the exception of the waters off the coast of Colombia. Fresh to occasional strong trades are expected in this area through Friday night-Saturday. A surface trough will enter the eastern Caribbean later tonight enhancing convection across the Lesser Antilles. ...HISPANIOLA... Clear skies prevail across the island as dry and stable northeast winds aloft persist due to an upper-level anticyclone centered near 16N85W. These conditions will continue through the remainder of the week and weekend. ATLANTIC OCEAN... A frontal system extends across the western portion of the basin analyzed as a stationary front from 26N80W to 27N77W then as a cold front from that point to 29N71W to 31N65W. Isolated showers are observed along the cold front. To the east, a broad 1019 mb surface high is centered near 24N64W. With this, a surface ridge extends across the basin. A cold front is entering our area of discussion extending from 30N53W to 29N45W to 31N37W with isolated showers mostly to the east of the front and north of 27N. Expect for the front to continue moving across the basin. Little change is expected elsewhere. For additional information please visit http://www.hurricanes.gov/marine $$ ERA