000 AXNT20 KNHC 141204 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 704 AM EST Thu Dec 14 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 0600 UTC surface analysis and satellite imagery through 1130 UTC. ...SPECIAL FEATURES... A cold front will move into the Gulf of Mexico by early Fri morning. Northerly winds will rapidly increase to fresh to near gale force behind the front by sunrise Fri, then will increase to minimal gale force offshore of Mexico, reaching to offshore of Veracruz Fri night. Seas will build to 8-12 ft W of the front with the strong to gale force winds. Gale-force winds are forecast to diminish by sunrise on Saturday. See latest NHC High Seas Forecast under AWIPS/WMO headers MIAHSFAT2/FZNT02 KNHC for more details. Strong high pressure will build N of the Caribbean by Friday evening resulting in a tight pressure gradient in the S central Caribbean where trades will increase to fresh to strong. The gradient will continue to strengthen through the weekend and gale force winds are forecast to pulse NW of the Colombian coast Fri night, Sat night, and Sun night. Seas will build to 8-14 ft in S central portions due to the gale and surrounding winds. See latest NHC 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 06N14W. The Intertropical Convergence Zone axis continues from 06N14W to 04N32W to 03N50W. Scattered moderate convection is from 03N to 08N between 17W and 30W. ...DISCUSSION... GULF OF MEXICO... A weak surface ridge anchored by a 1017 mb high near 25N83W dominates the eastern half of the basin. This surface pattern is supporting light to gentle variable winds, except for WSW moderate winds in the NE Gulf N of 27N. Low to middle level dry air continue to support clear skies S of 25N. Looking ahead, a cold front is forecast to enter the northern Gulf by early Friday morning, then reach from the Florida Big Bend area in the NE Gulf to near Tampico Mexico by Fri evening, then stall from Tampa to the Bay of Campeche on Sat before lifting back to the W and NW through Sun. Gale force winds are forecast along the coast of Mexico near Tampico Fri night and Sat. See special features for further details. CARIBBEAN SEA... The tail of a stationary front extends from eastern Cuba near 20N78W to 18N85W with possible isolated showers within 60 nm either side of the boundary. Ahead of the front, the remnants of a former cold front are analyzed as a trough from 19N79W to western Panama near 09N81W. Isolated showers are within 90 nm either side of the trough axis. Cloudiness associated with the front and surface trough extend to western and central Hispaniola with possible isolated showers. A shallow moist airmass moves across the SE basin supporting isolated showers S of 14N E of 70W. Fair weather is elsewhere. In addition to showers, fresh to strong winds are in the vicinity of the surface trough as indicated by latest scatterometer data. Light to moderate trades are in the remainder central and eastern basin. Winds are forecast to increase to 20-25 kt over the south-central Caribbean on Thu night, with gale conditions possible Sat night and Sun night as high pressure builds N of area. ...HISPANIOLA... Cloudiness prevail over Hispaniola due to the proximity of a surface trough and stationary front to the west. Isolated light showers are still possible through later this morning. Then, moisture will diminish as the trough continues to weaken and drift westward. ATLANTIC OCEAN... A cold front enters the forecast area near 30N59W and continues SW to 26N66W where it stalls continuing across the southern Bahamas into eastern Cuba. A surface trough is farther east and stretches from 30N55W to NE Dominican Republic. The cold front will continue to move SE while gradually dissipating today. A ridge will then build along 25N in the wake of the cold front. Another cold front is forecast to move off the NE Florida coast early Fri, reach from Bermuda to South Florida Sat, then reach from 24N65W to eastern Cuba early Sun. The remainder of the Atlantic Ocean is under the influence of a 1033 mb high pressure located just south of the Azores. This high extends a ridge SW to near the NE Caribbean. For additional information please visit http://www.hurricanes.gov/marine $$ Ramos