000 AXNT20 KNHC 240005 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 704 PM EST Tue Jan 23 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 1800 UTC surface analysis and satellite imagery through 2315 UTC. ...SPECIAL FEATURES... Caribbean Gale Warning: The combination of high pressure in the central Atlantic and lower pressures over northern Colombia will continue to bring pulses of strong to minimal gale force NE to E winds along and near the coast of Colombia during the overnight hours through Thu night and possibly beyond into the upcoming weekend. Seas are expected to be in the 9-14 ft range with these winds. Please read the latest NHC High Seas Forecast under AWIPS/WMO headers MIAHSFAT2/FZNT02 KNHC for more details. Gulf of Mexico Gale Warning: COLD FRONT FROM 29N83W TO 22N90W THEN STATIONARY TO 21N96W TO 18N95W. S OF 21N W OF FRONT NW WINDS 25 TO 35 KT. SEAS BUILDING TO 9 FT. The latest model guidance indicates that these gale wind conditions will persist longer than previously advertised, and will now linger into early Thu morning. During tonight, the cold front is forecast to reach from the Straits of Florida to across the Yucatan Peninsula, with the stationary portion transitioning back to a cold front across the southern Bay of Campeche. The cold front will weaken slowly as it moves across the SE Gulf Wed, and exiting the area by late on Wed. Please read the the latest NHC High Seas Forecast under AWIPS/WMO headers MIAHSFAT2/FZNT02 KNHC for more details. ...MONSOON TROUGH/ITCZ... The monsoon trough axis extends from Africa near 06N09W to 03N19W. The ITCZ continues WSW from 03N19W to 01S41W. Scattered moderate convection is N of the ITCZ within 30 nm either side of a line from 02N31W to 03N39W. Similar activity is within 60 nm S of the ITCZ between 36W-39W. ...DISCUSSION... ...GULF OF MEXICO... Please read the SPECIAL FEATURES section for details about the cold front and the gale-force winds that are associated with it. The cold front passes through NE Florida, into the SE part of the Gulf of Mexico, into the south central sections, and into the SW corner of the area. The front will reach from SW Florida to the Bay of Campeche tonight, then move slowly across the SE Gulf exiting the area by late Wed. Minimal gale conditions are forecast over the SW Gulf waters near Veracruz, Mexico this afternoon through Thu. Strengthening high pressure in the wake of the front will bring increasing winds and building seas across much of the Gulf waters Wed evening into Thu, with these conditions shifting across the E Gulf on Fri and Sat. ...CARIBBEAN SEA... Please read the SPECIAL FEATURES section for details about the gale-force winds for the area that is off the coast of Colombia. Broad upper level ridging is present across the western half of the basin, while broad inverted troughing is noted elsewhere. Upper level winds and satellite winds reveal a diffluent flow pattern over the SW Caribbean. This appears to support scattered moderate convection that is occurring from 10N to 13N W of 81W to inland southern Nicaragua and far northern Costa Rica. This activity is being sustained further by low-level speed convergence present there. Patches of low-level moisture advecting westward in the easterly flow are seen over the eastern Caribbean waters, and also approaching the northern Windward Islands. Scattered showers with gusty winds are possible with this moisture. Strong to minimal gale force trade winds are forecast along the the NW coast of Colombia during the overnight and early morning hours through Sun. A cold front currently located over the Gulf of Mexico will move slowly SE entering the NW Caribbean by late Wed, then stall and gradually dissipate from Central Cuba to Northern Belize on Thu. Strengthening high pressure in the wake of the front will produce fresh to strong NE-E winds across the Caribbean, including the Atlantic passages Thu evening through Sat. Moderate to fresh trades will continue across the tropical Atlc waters E of the Windwards through Fri, with fresh to strong NE winds forecast on Fri night through Sat night. ...ATLANTIC OCEAN... One surface trough is along 40W/41W from 24N to 31N. A second surface trough is along 60W/61W from 27N to 31N. A cold front moving off the NE Florida coast this afternoon, will reach a position from 31N70W to the Straits of Florida late Wed, from 31N65W to Central Cuba late Thu, from 24N65W to along the coast of central Cuba late Fri, then stall E to W along 22N Fri night through Sat night while dissipating. Strengthening high pressure in the wake of this front will produce strong to near gale force NE-E winds W of the front Thu through Sat. The strongest winds are expected S of 27N Fri and Sat with building seas of 12-14 ft E of the Bahamas. For additional information please visit http://www.hurricanes.gov/marine $$ mt