000 AXNT20 KNHC 042201 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 0005 UTC Thu Aug 5 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 along 24W from 22N southward, moving W around 15 kt. Scattered moderate convection is noted from 11N to 12N between 23W and 25W. A tropical wave is in the Atlantic Ocean along 31W from 22N southward, moving quickly W around 20 kt. Scattered moderate convection is noted from 10N to 14N between 30W and 34W. A tropical wave is in the Atlantic Ocean along 44W from 18N southward, moving W around 20 kt. Scattered moderate and isolated strong convection is noted from 09N to 11N between 44W and 48W. A tropical wave is in the Atlantic Ocean along 57W from 17N southward to across Suriname, moving W around 20 kt. Scattered moderate convection is noted from 10N to 13N between 54W and 58W, with additional convection near the axis over northern South America. A tropical wave is in the Caribbean Sea along 77W from 15N southward to near the Panama/Colombia border, moving W around 10 kt. Interacting with an upper-level low near Jamaica at 17N76W, scattered showers are noted over the central and south-central Caribbean, with additional activity over portions of northern Colombia. A tropical wave that was in the western Bay of Campeche is now inland over Mexico along 96W southward into the tropical Pacific Ocean, moving W around 10 kt. Isolated showers and thunderstorms are occurring over the SW Gulf of Mexico near this departing feature. ...MONSOON TROUGH/ITCZ... A monsoon trough extends from the Senegal coast near 15N17W to 1011 mb low pressure near 16N22W to 1013 mb low pressure near 13N27W to 10N40W to 10N55W. Scattered moderate and isolated strong convection is noted near the coast of Africa from 07N to 13N between 13W and 20W, and from 09N to 11N between 48W and 54W. Scattered moderate convection is noted from 09N to 12N between 27W and 30W, and from 09N to 12N between 35W and 43W. ...GULF OF MEXICO... A slow-moving cold front stretches westward from the Florida Big Bend to Corpus Christi, Texas. Numerous showers and scattered thunderstorms are evident across the Gulf north of 25N. Moderate to locally fresh winds and seas up to 6 ft are near these thunderstorms. A surface ridge extends west-southwestward from the Straits of Florida across the central Gulf to central Mexico. Convergent SE winds near the ridge axis are coupling with divergent winds aloft to trigger scattered showers and thunderstorms over the east-central Gulf and Florida Peninsula. An upper-level low near the eastern coast of Mexico at 28N98W is supporting isolated showers and isolated thunderstorms across the western Gulf. The surface ridge continues to support gentle to moderate winds and seas of 2 to 4 ft across the central and S Gulf. For the forecast, a slow-moving cold front from the Florida Big Bend to Corpus Christi, Texas will become stationary tonight over the northern Gulf of Mexico. On the Fri, the front will weaken as it lifts northward. Scattered showers and thunderstorms will continue over the northern half of the Gulf of Mexico through Fri. Moderate SW to W winds will prevail south of the front in the northeastern Gulf through this evening. Moderate to fresh E winds will pulse off the NW Yucatan Peninsula into the Bay of Campeche every night through Mon night in association with a diurnal trough. Elsewhere south of the front, a surface ridge will dominate the Gulf waters over the next several days producing gentle to moderate anticyclonic winds. ...CARIBBEAN SEA... Enhanced by divergent winds associated with an upper-level low near Jamaica at 17N76W, convergent trade winds are supporting scattered showers and isolated thunderstorms across portions of northern Colombia and adjacent coastal waters. The pressure gradient in the south-central Caribbean Basin has weakened nevertheless, earlier satellite scatterometer and altimeter data indicate moderate to fresh trades and seas of 4 to 6 ft in this area. Elsewhere in the basin, gentle to moderate trades and seas at 2 to 4 ft are evident. For the forecast, fresh trade winds across the south-central Caribbean will increase slightly, pulsing from fresh to strong Thu through Fri night near the coast of NE Colombia and NW Venezuela. Expect fresh east winds in the Gulf of Honduras from late afternoon through the nighttime hours, each day through at least Fri night. Fresh NE winds are expected in the Windward Passage during the evening hours, Fri evening through Sun evening. Gentle to moderate trades will prevail elsewhere. ...ATLANTIC OCEAN... Convergent S to SW winds to the south of a cold front off the Carolina coast to northeast Florida are supporting scattered showers and isolated thunderstorms west of 76W. Convergent trade winds are triggering similar conditions near and north of Hispaniola and Puerto Rico, and also near the Bahamas. An upper- level low southwest of the Canary Islands near 26N24W is inducing scattered showers and isolated thunderstorms from 21N to 27N between 20W and 27W. The subtropical ridge related to the Bermuda-Azores high persists over the north central and western Atlantic Basin. Moderate to locally fresh trades prevail across the Atlantic waters elsewhere north of the convergence zone, with gentle to moderate southerly flow south of the convergence zone, except locally fresh between 30W and 45W. Seas are in the 4 to 7 ft range across the Atlantic waters. For the forecast W of 65W, the cold front from 31N79W to St. Augustine Florida will become stationary tonight, then lift northward on Fri. Strong south to southwest winds and scattered showers and thunderstorms will continue just east of the front offshore NE Florida through this evening, with fresh continuing into Thu morning. Fresh winds will pulse north of Hispaniola, including the approaches to the Windward Passage, Thu night and Fri night. Otherwise, a surface ridge associated with the Bermuda- Azores high will persist for the next several days. $$ Lewitsky