000 AXNT20 KNHC 130515 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 0605 UTC Tue Jul 13 2021 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 31N. The following information is based on satellite imagery, weather observations, radar and meteorological analysis. Based on 0000 UTC surface analysis and satellite imagery through 0430 UTC. ...SPECIAL FEATURE... Gale ...TROPICAL WAVES... A newly analyzed Atlantic tropical wave is near 23W from 13N southward and moving W at 10 to 15 kt. Scattered showers and a few thunderstorms are seen from 03N to 12N between 20W and 31W. Another Atlantic tropical wave is along 4W from 12N southward and moving W at 15 to 20 kt. Scattered moderate to isolated strong convection is noted from 05N to 10N between 34W and 47W. A much weaker Atlantic tropical wave previously located near 50W has moved over French Guiana and Suriname. It has absorbed into a near-equatorial trough and is no longer identifiable. A Caribbean tropical wave is over central Cuba and southward to E Panama, and moving W at 15 to 20 kt. Aided by upper-level divergent winds, numerous showers and thunderstorms are occurring over central Cuba, the Florida Strait and near the Panama- Colombia border. ...MONSOON TROUGH/ITCZ... The monsoon trough extends from near the Gambia/Guinea-Bissau border at 12N15W to 08N28W to 08N42W. The ITCZ is seen farther W from 08N46W to near the Suriname coast. Scattered moderate to isolated strong convection is evident near the monsoon trough from 06N to 14N between the African coast and 20W, and near the ITCZ from 06N to 10N between 48W and 53W. For additional convection associated with the tropical waves, refer to the Tropical Waves section above. ...GULF OF MEXICO... Two broad upper-level lows, one is centered over the NW Gulf at 26N94W and another one near the Georgia-S Carolina border at 32N81W. Two modest surface troughs, one is across the N central Gulf at 28N89W and another one over the SW Gulf at 22N9%W. Interaction betweeen these surface and upper-level features is triggering scattered showers and isolated thunderstorms SE of New Orleans and over the Florida Panhandle, and over the SW Gulf just N of the Bay of Campeche. A surface ridge across the Gulf States will continue to support gentle SE to S winds and seas of 1 to 3 ft over the N Gulf. Gentle to moderate ENE to E trades and seas of 2 to 4 ft prevail across the central and S Gulf. Locally fresh winds and seas up to 6 ft are seen over the Florida Strait associated with the convection mentioned in the Tropical Waves section above. For the forecast, a surface ridge just north of the area will maintain gentle to moderate winds and slight to moderate seas across much of the Gulf through Fri. A surface trough will develop each day over the Yucatan and shift westward into the SW Gulf. This will support fresh to occasionally strong winds off the northwest Yucatan Peninsula and eastern Bay of Campeche during the overnight hours through mid week. ...CARIBBEAN SEA... Please refer to the section above for details on the tropical wave moving across the basin. Scatterometer data depicts fresh trades across most of the eastern and central Caribbean, with locally strong winds in the south-central Caribbean offshore of Colombia. Maximum seas are estimated to be 10 ft in the south-central Caribbean, mainly off the coast of Colombia, and 6 to 8 ft over the eastern Caribbean where fresh tradewinds follow the tropical wave moving across the basin. Moderate E to SE winds and 3 to 5 ft seas are noted over the northwest Caribbean. In addition to the convection mentioned in the Tropical Wave section, scattered moderate convection is ongoing off Costa Rica and eastern Nicaragua west of 80W. For the forecast, the tropical wave in the central Caribbean will move west of the basin the middle of the week. High pressure centered north of the region will support strong tradewinds and building seas into Wed, including strong nocturnal NE winds across the Windward Passage Tue night into Wed. Winds and seas will diminish through Fri. ...ATLANTIC OCEAN... Please see the Tropical Waves and Monsoon Trough/ITCZ sections above for information on convection across the basin. A surface ridge extends from the central Atlantic across Bermuda to the central Florida coast. This pattern is supporting gentle to moderate E to SE trade winds north of 25N west of 35W with 3 to 5 ft seas over open waters. Fresh trades are noted south of 25N west of 35W to 60W with 6 to 9 ft seas. Fresh to locally strong E winds are south of 25N and west of 60W over waters surrounding the Greater Antilles with 4 to 6 ft seas. Divergence aloft associated with an upper low now centered over the west Atlantic is supporting scattered moderate convection mainly west of 75W. To the east, another upper level low is centered near 28N53W and it is reflected at the surface as a trough along 50W. Scattered showers are noted along and west of the trough north of 25N between 50W and 59W. For the forecast, the surface ridge will lift north to along 32N through Tue. Strong winds will continue to pulse off Hispaniola and into the Windward Passage Tue night into Wed. Winds and seas will diminish across the region through Fri as the area of high pressure weakens. $$ NATIONAL HURRICANE CENTER