000 AXNT20 KNHC 212326 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 726 PM EDT Sun Jul 21 2019 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 2300 UTC. ...SPECIAL FEATURES... Caribbean Gale Warning: A tightening pressure gradient will bring NE to E gale force winds tonight from 22/00Z to 22/12Z near the N coast of Colombia from 11N-13N between 74W-76W. Seas are expected to be between 9-14 ft. After 12Z Monday morning, winds will remain below gale force. ...TROPICAL WAVES... An eastern Atlantic tropical wave is along 30/31W S of 16N, moving W at 15-20 kt. Scattered showers are from 05N-07N between 25W-31W. A tropical wave has been added to the analysis along 43W from 06N-21N. This wave is completely embedded within the middle of a strong outbreak of Saharan dust, and no convection is present. A central Atlantic tropical wave is along 53/54W S of 18N, moving W at 10-15 kt. Scattered showers and isolated tstorms are seen south of 07N between 50W-57W, including over portions of Suriname and French Guiana. An eastern Caribbean tropical wave is along 64W south of 19N and is moving W around 15 kt through the Virgin Islands. Isolated showers are possible within 180 nm of the wave axis north of 15N. Scattered tstorms are over eastern Venezuela and near Trinidad. A western Caribbean tropical wave is along 81W S of 18N, moving W around 15 kt. No significant convection is noted north of 10N. However, numerous moderate with embedded isolated strong convection is over Panama and the East Pacific, with a few of the storms spilling into the SW corner of the Caribbean south of 10N. ...MONSOON TROUGH/ITCZ... The monsoon trough extends from the coast of Guinea-Bissau near 11N15W to 08N24W to 07N34W. The ITCZ begins near 07N34W to 06N43W to 07N52W, then continues W of a tropical wave from 09N55W to the coast of Venezuela near 09N61W. Aside from the convection mentioned in the Tropical Waves section, scattered showers are seen within 180 nm S of the ITCZ between 34W-48W. GULF OF MEXICO... An upper level trough axis is stretching across the western Atlantic from 32N78W southwestward to 26N86W to the SW Gulf near 21N97W. An upper-level high is centered over western Kentucky and southern Illinois. Upper-level divergence of the upper-level northeasterly flow in between the upper trough and upper high is being maximized over the northern Gulf of Mexico. The upper-level divergence is enhancing scattered moderate convection from 25N-29N between 88W-96W. Scattered moderate convection is also along the west coast of the Florida Peninsula. Elsewhere north of 24N east of 97W, scattered showers and isolated tstorms are present. An area of upper-level diffluence is enhancing scattered moderate convection over the western Yucatan Peninsula and eastern Bay of Campeche from 19N-22N between 88W-91W. Isolated showers and tstorms are also seen over the Yucatan Channel. At the surface, there is weak ridging and not much of a pressure gradient. Therefore, winds are gentle across most of the Gulf of Mexico, except locally stronger near any strong thunderstorms. A ridge along the northern Gulf of Mexico will retreat E Tuesday night and allow a cold front to move into the northern Gulf. The front will then stall and weaken Wed and Thu. Gentle to moderate winds will continue across most of the basin, except for fresh winds pulsing to the W of the Yucatan peninsula at night. CARIBBEAN SEA... Mid to upper level troughing is over the eastern Caribbean east of about 68W. However, most of the upper level divergence from this is giving way to convection in the Atlantic. Scattered showers and tstorms are over Puerto Rico, Hispaniola, Jamaica and portions of Cuba. Scattered showers and isolated tstorms are over the NW Caribbean north of 18N west of 81W. Other than the convection mentioned in the Tropical Waves section, and the convection in the NW Caribbean, no other significant convection is seen across the basin. Strong to near gale force trades are seen on Sunday morning's ASCAT pass from 11N-14N between 73W-77W. High pressure N of the area will support fresh to strong trade winds over the central Caribbean Sea through next week. Winds along the coast of Colombia will reach gale force tonight. See the Special Features section above for information on the Caribbean Gale Warning. Fresh easterly winds will pulse over the Gulf of Honduras tonight and Mon night. ATLANTIC OCEAN... An upper level trough stretches from 32N78W across northern Florida and into the Gulf of Mexico. Scattered showers and isolated tstorms are west of 78W from 26N-30N. A surface trough extends from 27N72W to the SE Bahamas. This trough is producing scattered showers and isolated tstorms from 21N-27N between 67W- 75W. The trough will move W to reach the waters between the Bahamas and Florida late Monday. This trough has a low chance of developing into a tropical cyclone during the next 48 hours, and it should enhance rainfall over the Bahamas through Monday. Surface ridging covers the remainder of the subtropical Atlantic from 20N-30N, east of 66W. The ridge will maintain gentle to moderate east to southeast winds across the western Atlantic through Tuesday night. The ridge will start retreating eastward on Tuesday night, enabling a trough to move over the NW waters from Florida Wed morning. Fresh to occasionally strong E winds will pulse N of Hispaniola each night through the middle of next week. For additional information please visit http://www.hurricanes.gov/marine $$ Hagen