000 AXNT20 KNHC 281759 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1805 UTC Mon Sep 28 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 1200 UTC surface analysis and satellite imagery through 1745 UTC. ...SPECIAL FEATURES... ...GULF OF MEXICO GALE WARNING... A strong cold front will enter the NW Gulf today, then reach the SE Gulf and Straits of Florida Wed evening. Behind the front, gale force N winds are expected Tue and Tue night over the west- central and SW Gulf of Mexico, mainly south of 26N and west of 95W. Seas are expected to build to 10-13 ft within the gale area by Tue morning. These conditions are expected to dissipate by early Wed. Please see the latest High Seas Forecast at https://www.nhc.noaa.gov/text/MIAHSFAT2.shtml for more details. ...TROPICAL WAVES... A tropical wave axis is along 34W from 02N-18N, moving W at 15 kt. Scattered moderate convection is from 03N-11N between 31W- 36W. A tropical wave axis is along 54W from 04N-18N, moving W at 10-15 kt. Scattered moderate convection is from 10N-18N between 51W-57W. An eastern Caribbean tropical wave axis is along 66W from 03N-18N, moving W at 10 kt. Scattered to numerous moderate convection is noted from 11N-17N between 63W-69W. ...MONSOON TROUGH/ITCZ... The monsoon trough extends from the coast of Africa near 12N16W to 09N29W. The ITCZ extends from 07N36W to 11N50W, then resumes west of a tropical wave from 11N57W to 10N63W. Besides the convection mentioned in the tropical wave section, scattered showers are noted along the boundary and east of 29W, and about 200 nm on either side of the ITCZ. Gulf of Mexico... Refer to the section above for details on the Gale Warning currently in effect for the southwest Gulf. A mid-level trough is located over the northern Gulf of Mexico from the Florida Panhandle to southern Texas. East of this trough, mid-level SW winds are transporting moist air from the Bay of Campeche to the central and NE Gulf. As a result, scattered moderate convection is noted across the south-central and the northeast portion of the basin along 23N and east of 90W. Elsewhere, scattered showers are noted near the western Gulf coast. Recent ASCAT data depicts light to gentle winds over the eastern Gulf, and moderate to locally fresh S winds over the central and western portions. In the forecast, the strong cold front will enter the NW Gulf this afternoon, then reach the southeastern Gulf waters Wed and the Straits of Florida by Wed evening. In the wake of the front, strong northerly winds are expected in the western half of the basin, with gale force winds expected west of 95W on Tue. A secondary front will drop south to the northern Gulf early on Fri and reach the far southwestern Gulf by Fri evening. Strong high pressure will build in behind this front. The pressure gradient between the front and a tropical wave that will approach the western Caribbean is expected to freshen the northeast winds over most of the southeastern Gulf by the end of the week. CARIBBEAN SEA... A tropical wave is moving over the E Caribbean. Please refer to the Tropical Waves section above for details. Scattered moderate convection is noted in the SW Caribbean, the east Pacific monsoon trough and 1009 mb low north of Colombia is enhancing scattered showers S of 12N and west of 75W. ASCAT data depicts moderate to fresh winds over the south-central Caribbean north of Colombia and over the Gulf of Honduras, while gentle to moderate trades prevail elsewhere. Fresh trades are also noted near the Lesser Antilles east of the tropical wave axis. Moderate to fresh trade winds over the central Caribbean will increase to fresh to strong speeds by mid-week. Moderate winds will continue elsewhere, except for gentle winds over the northwestern Caribbean. A tropical wave, currently located along 66W, will continue moving west across the basin accompanied by active weather and enhanced winds. ATLANTIC OCEAN... Refer to the section above for details on the tropical waves moving across the basin. Over the western Atlantic, scattered moderate convection is N of the Bahamas north of 28N-31N between 75W-81W near a trough that extends southwest from 33N74W to 31N76W. Further east, a surface trough extends from 33N71W to 26N70W. Another trough extends from 31N60W to 25N58W. Neither of these troughs have any significant Convection in the vicinity. Surface ridging prevails across the remainder of the basin. Over the western Atlantic, weak high pressure is maintaining generally gentle to moderate winds across the area. The high pressure will begin retreat eastward through Wed in response to a cold front that will be moving across the southeastern U.S. This cold front will reach the southeastern U.S. coast Tue night and move over the northwest part of the area through Wed. The front will begin to weaken as it reaches from near 31N74W to South Florida by Wed night and become stationary from 31N73W to the Straits of Florida by late Thu through Fri night. Scattered showers and thunderstorms are expected ahead of the cold front. $$ MTorres