000 AXNT20 KNHC 291433 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1205 UTC Thu Jul 29 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 0600 UTC surface analysis and satellite imagery through 1130 UTC. ...TROPICAL WAVES... An Atlantic tropical wave is near 29W from 18N southward and moving west around 10 kt. Scattered moderate convection is evident from 05N-09N between 26W-33W. Another Atlantic tropical wave is near 49W from 19N southward and moving west around 20 kt. No significant convection is noted currently in association with the wave. A Caribbean tropical wave is near 65W from 17N southward across N Venezuela, and moving west at 5 to 10 kt. Aided by divergent flow related to an upper-level low just northwest of Puerto Rico, scattered moderate convection is seen from 10N-15N between 60W-65W. Another Caribbean tropical wave is near 79W from 13N southward through E Panama into the Pacific Ocean, and moving west near 10 kt. Scattered showers and isolated thunderstorms are occurring across Panama and adjacent waters. ...MONSOON TROUGH/ITCZ... A monsoon trough extends across the coast of Mauritania at 18N17W to 05N40W. There is no coherent ITCZ at this time west of the monsoon trough. In addition to the convection associated with the tropical wave near 29W, scattered moderate convection exists from 05N-12N east of 23W. ...GULF OF MEXICO... A surface trough is noted from 21N96W to 26N94W. The diurnal trough is seen in the SW Gulf from 20N92W to 21N90W. Isolated moderate convection exists west of 92W. Scattered moderate convection is noted north of 27N east of 87W. Elsewhere surface ridging extends westward across Florida and into the E Gulf of Mexico. Fresh SE winds are occurring over the SW Gulf, while tranquil conditions prevail elsewhere. Seas are 2-4 ft across the Gulf. For the forecast, the surface trough drifting west across the NW Gulf is accompanied by scattered showers and isolated thunderstorms. The trough will drift over the NW Gulf through this evening while gradually weakening. In its wake, the Atlantic high pressure ridge will begin to build westward into the Gulf waters later today, with a high pressure cell developing over the E central Gulf. This high will drift westward and dominate the Gulf region during the upcoming weekend then reorganize over the E Gulf late Mon. ...CARIBBEAN SEA... A moderate north-south pressure gradient between ridging north of the Caribbean and lower pressure over N South America is contributing toward fresh to strong NE to E trades over the S central Caribbean and just south of Hispaniola. Elsewhere the trades are gentle to fresh. Seas are 6-8 ft in the central Caribbean, 4-6 ft in the E Caribbean, and 3-5 ft in the W Caribbean. Besides the convection associated with the tropical waves near 65W and 79W, no significant deep convection is observed. For the forecast, freshening tradewinds are expected across E and central portions of the Caribbean through tonight as the Atlantic ridge builds modestly across the W Atlantic. Fresh to strong trades will prevail across south central portions as well as the south central coast of Hispaniola through Sun night before the ridge begins to weaken. Strong winds to around 30 kt are expected at night near the coast of Colombia and in the Gulf of Venezuela Fri night through Mon night. ...ATLANTIC OCEAN... Refer to the Tropical Waves and Monsoon Trough/ITCZ sections above for convection across the Atlantic Basin. The Atlantic ridge extends west-southwest from the 1028 mb Azores High across W central Atlantic to Florida. The ridge is sustaining light to gentle trades across all of the waters, except for fresh SE winds just north of Hispaniola. Seas are 6-7 ft south of 22N and 4-5 ft north of 22N. Scattered moderate convection is noted north of 30N between 65W-75W in association with a sharp upper-level trough. For the forecast W of 65W, the Atlantic ridge will dominate the forecast waters through the period, while a surface trough will remain over or just off the coast of the SE United States. Expect fresh to locally strong easterly winds late afternoon through the night just off the N coast of Hispaniola, including approaches to the Windward Passage, most of the forecast period. Moderate to fresh S to SW winds are expected across the far NW waters Sun night through Mon night. $$ Landsea