000 AXNT20 KNHC 172337 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 0005 UTC Thu Dec 17 2020 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. ...MONSOON TROUGH/ITCZ... The monsoon trough passes through the coast of Sierra Leone near 08N13W to 04N17W. The ITCZ continues from 04N17W to 01S44W. Scattered moderate to isolated strong convection is noted from 02N-12N E of 21W, and scattered moderate convection between 21W 40W. GULF OF MEXICO... Strong upper level SW wind flow covers the entire Gulf of Mexico and is producing a very progressive upper level pattern across the southeastern U.S. At the surface, a cold front extends from southwest FL to near 24N82W then becomes stationary to central Bay of Campeche near 18N93W. Scattered showers and thunderstorms are noted in the vicinity of the front. A 10287mb high is over eastern Texas and is driving fresh to strong northerly winds behind the front south of 22N and west of 90W, where seas are still 8-10 ft in north swell. Fresh northerly winds are noted in the Bay of Campeche in addition to moderate northerly winds in the western Gulf. Seas for the rest of the basin are 3-6 ft. For the forecast, fresh to strong northerly winds will continue north of the front across the Bay of Campeche through Fri morning before diminishing. High pressure will build across the Gulf Fri and Sat to produce fresh to locally strong E to SE winds across the basin. The next cold front will move into the northwest Gulf by Sat evening and move slowly SE through Mon, reaching the Florida Panhandle to the SW Gulf CARIBBEAN SEA... An upper level ridge causing subsidence dominates the NW Caribbean and is producing very stable conditions across most of the basin. A surface trough extending south of Cuba from 16N82W to 21N82W is producing some isolated showers. Elsewhere, a cluster of isolated moderate convection is near 09N between 80W-83W, off the coast of Costa Rica and Panama City. Fresh to strong E-NE winds are located off the coast of Colombia where seas are 7-9 ft. Gentle to moderate trades are noted in the eastern and central Caribbean with light to gentle winds in the NW Caribbean where seas are 3-6 ft. The stationary front will exit the Gulf of Mexico and move into the NW Caribbean tonight. The front will weaken and move slowly SE across the Yucatan Channel and NW Caribbean through Fri before dissipating. Strong high pressure north of the front will produce fresh to strong NE tradewinds across much of the area Fri and Sat before diminishing modestly Sun and Mon. ATLANTIC OCEAN... A cold front stretches from 31N72W to South Florida coast near 26N80W. A pre-frontal trough is located north of the Bahamas from 29N74W to just north of Cuba near 24N79W. Scattered showers are noted north of 31N and about 90 nm ahead of the front. Gentle to moderate NW winds are noted behind the cold front and moderate southerly winds are ahead of the front. Seas are up to 7 ft near the Florida coast. In the central Atlantic, an elongated trough is located near 29N54W to just north of Hispaniola near 20N69W. No significant convection is associated with this feature. Farther east, surface ridging extends across the eastern and central Atlantic anchored by a 1027 mb high near 29N29W. Light to gentle winds prevail with seas 5-8 ft. The cold front will move slowly SE, reaching from near Bermuda through the central Bahamas to central Cuba Fri afternoon. Expect fresh to strong southwesterly winds ahead of the front N of 29N through Fri. The front will gradually weaken and become E to W aligned along 24N Sun. High pressure will prevail north of the front. $$ Torres