000 AXNT20 KNHC 292144 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 0005 UTC Wed Jun 30 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 1800 UTC surface analysis and satellite imagery through 2130 UTC. ...TROPICAL WAVES... A tropical wave is in the Atlantic Ocean near 35W/36W from 15N southward, moving W at 15 to 20 kt. Scattered moderate and isolated strong convection is noted from the equator to 03N between 31W and 36W, and from 04N to 11N between 35W and 42W. This area continues to show signs of organization. Additional development of this area is possible during the next several days as it moves generally west- northwestward. Please read the latest Tropical Weather Outlook at www.hurricanes.gov, for more information. A tropical wave is in the Atlantic Ocean near 51W/52W from 17N southward, moving W at around 15N. A 1009 mb surface low is analyzed along the tropical wave near 12N52W. Scattered moderate and isolated strong convection is noted from 12N to 17N between 49W and 55W. Scattered moderate convection is noted from 09N to 16N between 55W and 60W. Some slow development of this area is possible later this week while the system moves westward to west- northwestward, likely reaching the Lesser Antilles by Wed night. Regardless of development, this area could bring locally heavy rainfall to portions of the Lesser Antilles during the next few days. Please read the latest Tropical Weather Outlook at www.hurricanes.gov, for more information, and refer to your national meteorological agency for more details on any potential impacts. A tropical wave is in the Caribbean Sea near 58W/59W from just south of the eastern Dominican Republic to over western Venezuela, moving W at 10 to 15 kt. No significant convection is occurring over water with this wave, however some showers and thunderstorms have developed over portions of Venezuela with the assistance of daytime heating. A tropical wave is in the Caribbean Sea near 85W from 18N southward across eastern Honduras, central Nicaragua and western Costa Rica, moving W at around 10 to 15 kt. Scattered moderate and isolated strong convection is noted from 11N to 19N between 80W and 85W with additional deep convection over land. ...MONSOON TROUGH/ITCZ... The monsoon trough extends from the coast of Africa near 13N17W to 10N21W to 09N45W. Scattered moderate and isolated strong convection is noted from 01N to 05N between 19W and 26W. GULF OF MEXICO... An upper-level trough runs west-southwest from near the Florida Panhandle across the northern Gulf to over northern Mexico. Divergent flow south of these features is coupling with convergent SE winds to trigger numerous showers and thunderstorms across much of the Gulf basin and surrounding land areas early this evening. A 1011 mb surface low is analyzed near Tampico, Mexico near 22N97W. Scattered moderate and isolated strong convection is noted from 19N to 16N west of 95W. Fresh to near gale force winds and seas of 5 to 8 ft are also noted from 22N to 27N west of 95W. Seas are 3 to 5 ft elsewhere.Moderate to locally fresh E-SE winds prevail across the remainder of the basin, except gentle to moderate south of 22N. For the forecast, a ridge will dominate the Gulf waters over the next several days producing mainly moderate E to SE winds. Fresh E to SE fresh winds are expected at night near the western Yucatan Peninsula through Fri due to local effects induced by a thermal trough. Another trough will persist over the SW Gulf over the next 2 or 3 days producing showers and thunderstorms. Winds and seas could be higher near thunderstorms. CARIBBEAN SEA... Refer to the Tropical Wave Section above for more detail information on convection and further details. Scattered moderate to strong convection is noted in the SW Caribbean south of 22N and west of 78W including over Panama. Otherwise, no significant convection is noted across the basin south of 18N and east of 80W with a dry trade-wind. Fresh to strong trades are noted in the central Caribbean south of 18N, and in the NW Caribbean north of 16N and west of 84W. Moderate to locally fresh trades prevail elsewhere, except gentle to moderate south of 11N. Seas are in the 6 to 10 ft range in the central Caribbean, 5 to 8 ft in the NW Caribbean, and mainly 4 to 7 ft elsewhere. For the forecast, building high pressure N of the Caribbean Sea combined with the Colombian low will bring increasing winds and seas across the basin, particularly across the south-central Caribbean through early Thu. ATLANTIC OCEAN... Ridging dominates the waters west of 65W with moderate to locally fresh E-SE flow. Seas are 3 to 5 ft across this area east of the Bahamas. Scattered showers and thunderstorms are occurring west of 76W/77W, as well as from 20N to 27N between 65W and 71W due to mid-upper level divergence. To the east, a stationary front extends from 31N35W to 28N54W to 30N58W. Isolated showers are possible near this feature. High pressure ridging prevails both north of and south of the front. Light to moderate anticyclonic winds prevail north of 25N and east of 65W, along with mainly 3 to 5 ft seas. Moderate to locally fresh trades are south of 25N and north of the convergence zone, except fresh to strong from 12N to 16N between 48W and 54W near a vigorous tropical wave and attendant low pressure area. Seas are mainly 5 to 7 ft across this area, except 7 to 9 ft near the area of fresh to strong winds. Fresh to strong N-NE winds are also noted west of the coast of Africa to 20W, north of 19N due to a locally tight pressure gradient, where seas are 6 to 9 ft. For the forecast W of 65W, the Atlantic ridge will build westward and dominate the forecast waters the remainder of the week. Fresh to strong winds are expected just N of Hispaniola Thu night through Sun night due to the pressure gradient between the Atlantic ridge and a couple of tropical wave passages over the Caribbean Sea. $$ Lewitsky