000 AXNT20 KNHC 211204 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 704 AM EST Wed Feb 21 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: Strong high pressure over the western Atlc and low pressure over South America are combining to maintain a tight surface pressure gradient over the Caribbean. This pattern is supporting winds reaching gale force strength along the coast of Colombia from 10N to 13.5N between 73W and 77.5W. Wave heights within the area of gale force winds are currently ranging between 10 feet and 16 feet. This synoptic setup is expected to remain in place through Fri morning. Please read the latest NHC High Seas Forecast under AWIPS/WMO headers MIAHSFAT2/FZNT02 KNHC for more details. ...MONSOON TROUGH/ITCZ... The monsoon trough passes through coastal sections of Sierra Leone near 08N13W to 06N16W. The ITCZ continues from 06N16W, crossing the Equator near 22W, to 02S32W, to near the coast of Brazil near 03S39W. Convection: Scattered moderate and isolated strong convection is present from 02N to 05N between 06W and 12W. Scattered moderate convection is noted from 01S to 02N between 17W and 25W and from 04S to 00N between 27W and 37W. ...DISCUSSION... GULF OF MEXICO... Upper level SSW wind flow is moving from southern Mexico, across Texas and Louisiana and the Gulf of Mexico W of 95W. Broad upper level ridging dominates the basin and is currently suppressing convection over all of the basin except along the upper Texas coast. Strong surface high pressure across the W Atlantic Ocean will persist, with a ridge extending W across the U.S.A. Gulf coast states, in order to produce fresh return flow across most of the basin, except for strong winds through the Straits of Florida and across central sections of the Gulf. A weak cold front will move slowly into the far NW waters on Sunday, and stall there on Sunday night. CARIBBEAN SEA... Please read the SPECIAL FEATURES section for details about the Gale Warning for the waters that are near the coast of Colombia. A surface ridge passes across central Cuba, to 19N82W in the NW corner of the area, to southern Costa Rica. Surface high pressure across the NW Atlantic Ocean will build S across the region through Wednesday, and then settle across the Bermuda area through the end of the week. Fresh-to-strong trade winds will prevail across the Caribbean Sea and the Tropical N Atlantic waters through Thursday, with nocturnal winds pulsing to gale-force off the coast of Colombia. High pressure will weaken through the weekend, leading to diminishing winds and seas. ATLANTIC OCEAN... An upper level trough passes through 32N34W to 23N53W to 24N48W, to 19N60W. A cold front passes through 32N30W, to 23N40W and 21N53W. A dissipating cold front continues from 21N53W to 21N62W. Broken to overcast low level clouds and possible rainshowers are to the NW and N of the line that passes through 32N27W 22N40W 18N60W 18N68W. A surface ridge passes through 32N68W, beyond central Cuba, into the NW corner of the Caribbean Sea. A W Atlantic Ocean ridge will persist along 33N-34N through Thursday, and then it will drift SW, and slowly weaken through the weekend. Gentle-to-moderate winds will prevail N of 25N, with fresh-to-strong winds S of 25N through Thursday. NNE swell will move through the waters E of 65W through Friday night. For additional information please visit http://www.hurricanes.gov/marine $$ McElroy