000 AXNT20 KNHC 301206 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 705 AM EST Tue Jan 30 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 0600 UTC surface analysis and satellite imagery through 1130 UTC. ...SPECIAL FEATURES... Caribbean Sea Gale Warning: The combination of a surface ridge in the west-central Atlantic and a 1006 mb low in South America near 10N75W is supporting minimal gale-force winds pulsing each night near the coast of Colombia, with seas in the 10 to 13 ft range. Expect winds to reach gale-force until around dawn today, then continue each night until at least Friday morning. See the latest NHC High Seas Forecast under AWIPS/WMO headers MIAHSFAT2/FZNT02 KNHC for more details. Gulf of Mexico Gale Warning: Strong high pressure ridging southward along the Sierra Madre Oriental mountains behind a cold front exiting the Gulf of Mexico will support gale force winds off the coast of Veracruz until around dawn this morning south of 21N and west of 95W, with seas running between 10 and 13 ft. Winds and seas will diminish during the day Tuesday as high pressure shifts eastward. See the latest NHC High Seas Forecast under AWIPS/WMO headers MIAHSFAT2/FZNT02 KNHC for more details. ...MONSOON TROUGH/ITCZ... The monsoon trough extends from Liberia on the coast of Africa near 06N10W to 05N15W. The ITCZ continues from 05N15W to 01N40W to the coast of Brazil near 01S50W. Scattered moderate and isolated srong convection is present from 01N to 04N between 09W and 25W and also 02S to 03N between 36W and 42W. ...DISCUSSION... ...THE GULF OF MEXICO... Please read the SPECIAL FEATURES section for details in reference to a gale-force wind event in the SW Gulf of Mexico. A strong surface ridge extends southward from southern Texas along the coast of Mexico, to the Isthmus of Tehuantepec of southern Mexico. One cold front has moved through the basin completely. A second cold front now passes through the Florida Panhandle, to SE Louisiana, to the middle Texas Gulf coast. This front is bringing a second shot of comparatively colder air. Minimal gale force winds will continue in the SW Gulf near Veracruz, Mexico through early this morning. The wind speeds and sea heights are forecast to diminish from W to E across the Gulf region during the rest of today. The current Texas-to-Isthmus of Tehuantepec ridge will dominate the area through Thursday. The next cold front is forecast to enter the northern Gulf waters on Friday. ...THE CARIBBEAN SEA... Please read the SPECIAL FEATURES section for details regarding gale-force wind conditions near the coast of Colombia. A cold front passes through NW Cuba, to southern Belize, and central Guatemala. Precipitation: isolated moderate to locally strong rainshowers cover the NW Caribbean Sea from 15N to 20N from 83W westward. The front will reach from eastern Cuba to the Gulf of Honduras this evening, where it will remain nearly stationary through Wed evening, then dissipate across the basin on Thu. Fresh to strong N-NE winds and building seas are expected NW of the front. Strong high pressure that is to the north of the area is supporting fresh to strong trade winds through much of the east- central Caribbean, including the Windward Passage. Buoy and altimeter data were indicating sea heights ranging from 8 to 11 ft in the area of strongest winds. The gradient will relax across the region as the high pressure shifts eastward ahead of the cold front in the Yucatan Channel. High pressure building north of the area behind the front will support fresh to strong trade winds once again over much of the central and eastern Caribbean Sea and tropical Atlantic west of 55W later in the week. Strong to minimal gale force winds are expected near the coast of Colombia primarily late at night and into the early morning hours through Thursday night. ...THE ATLANTIC OCEAN... A cold front passes through 32N71W, across the NW Bahamas, and beyond NW Cuba, into the NW corner of the Caribbean Sea. Scattered moderate to isolated strong rainshowers are within 30 nm to 45 nm on either side of 25N76W beyond 32N67W. A deep layer occluded low pressure center is near 27N49W. Scatterometer data during the early-morning hours were indicating that gale force winds were north of 31N ahead of the cold front, and 25-30 kt winds were on the northern side of the low in the central Atlantic Ocean. Upper level cyclonic wind flow covers most of the central Atlantic. A surface ridge passes through 32N59W, to 26N64W, to Hispaniola. An eastern Atlantic Ocean surface ridge passes through 32N28W to the Cabo Verde Islands. A 1015 mb low pressure center is near 29N13W off the coast of southern Morocco. The low pressure center is forecast to dissipate during the next 24 hours. The Meteo- France forecast calls for strong to near- gale winds for the area. The low is forecast to drift southward during the next 24 hours. The front will reach from 31N65W to eastern Cuba by Tue evening, from 24N65W to the easternmost tip of Cuba by Wed evening where it will remain nearly stationary through Thu evening. Fresh to strong NW-N winds will dominate the entire area west of the front, including the Old Bahama Channel by this evening. Similar marine conditions are expected early on Wed. High pressure in the wake of the front will dominate the region through Thu. Another cold front is forecast to arrive over the north waters on Fri afternoon. 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