000 AXNT20 KNHC 230608 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 0605 UTC Fri Jul 23 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 0550 UTC. ...SPECIAL FEATURES... Caribbean Gale Warning: The pressure gradient between the Atlantic ridge and the Colombian/Panamanian low will support gale force winds off the coast of the Colombia tonight with 8 to 12 ft seas. The strongest winds will be within 90 to 120 nm of the Colombian coast, mainly between Barranquilla and Santa Marta. Strong to near gale force winds will also impact most of the south-central Caribbean as well. For more information, please see the High Seas Forecast issued by the National Hurricane Center at https://www.nhc.noaa.gov/text/MIAHSFAT2.shtml Heavy Rainfall in Southern Central America: High moisture levels, persistent strong trade wind flow, and favorable conditions aloft will together support heavy rainfall for much of southern Central America through early next week. The heaviest rain is expected over the Caribbean coast of Costa Rica and southeast Nicaragua. These rains could cause significant flooding and mudslides in some areas. Currently, scattered moderate convection is noted along the Caribbean coast from SE Nicaragua through western Panama. ...TROPICAL WAVES... An Atlantic tropical wave extends its axis along 53W, south of 18N, moving W near 15 to 20 kt. Scattered moderate convection is evident South of 12N between 50W and 54W. Another tropical wave is over the eastern Caribbean along 62W, south of 18N, moving W at near 15 kt. No significant convection is evident near this tropical wave. A third tropical wave is along 76W, south of 24N, moving at 10 to 15 kt. This wave is producing scattered moderate convection along the wave axis south of 20N. ...MONSOON TROUGH/ITCZ... The monsoon trough enters the Atlantic Ocean near Guinea-Bissau near 12N16W and extends SW to 11N17W to 12N31W. The ITCZ continues from 10N31W to 10N45W. Scattered moderate to isolated strong convection is noted within 120 nm south of these features between 35W and 50W. GULF OF MEXICO... 1021 mb high pressure near 26N88W is the major feature over the Gulf of Mexico. This is supporting moderate E to SE winds across the west-central Gulf and Bay of Campeche with 2 to 4 ft, and light to gentle breezes elsewhere with seas 2 ft or less. Scattered showers and thunderstorms along the Florida Peninsula have drifted west into the offshore waters north of Key West. For the forecast, the Bermuda High extends across Florida to a second 1021 mb high across the N central Gulf of Mexico. High pressure ridging will continue to sink southward and provide tranquil conditions across the basin through the weekend and early next week. Fresh to locally strong E to SE winds will pulse tonight NW of the Yucatan Peninsula. CARIBBEAN SEA... A Gale Warning is in effect for the south-central Caribbean. Please see the Special Features section for more details. A tropical wave is moving across the basin. Refer to the section above for details. Fresh to strong trades prevail across the central Caribbean, including the Windward Passage, and the Gulf of Honduras, with fresh trades in the eastern Caribbean. Gentle to moderate winds are found elsewhere. Seas are 7-9 ft in the central Caribbean and 5-7 ft elsewhere, except for 2-4 ft south of Cuba. For the forecast, The Atlantic ridge is centered on a 1030 mb high near 34N42W. The resultant pressure gradient will support fresh E winds pulsing to strong in the afternoon and evening north of Hispaniola through Fri. Moderate to fresh trades will prevail elsewhere south of 20N. A low along a frontal boundary will sink southward during the weekend off the NE Florida coast. Environmental conditions are forecast to be marginally conducive for some gradual development over the weekend and into early next seek while the system drifts slowly offshore of the southeastern United States. Regardless of development, showers and thunderstorms and moderate to fresh winds can be expected over the weekend off the Florida coast. ATLANTIC OCEAN... A few showers and thunderstorms are noted north of 28N between 70W and 75W, related to divergent flow aloft between an upper trough in that region and an upper low centered near 25N65W. A surface ridge extends from 1028 mb high pressure near 34N49W to east-central Florida. Fresh to strong E winds are active along the north coast of Hispaniola. This is in an area where a tropical wave is moving through, and seas may be reaching up to 6 ft. Elsewhere moderate to fresh E winds persist south of the ridge over the tropical Atlantic and 6 to 8 ft seas, highest east of leeward Islands. Gentle winds and slight seas persist along and north of the ridge axis, with 3 to 5 ft seas. Farther east, strong to near gale force winds are east of 20W, surrounding the Canary Islands. Moderate to fresh NE winds are noted elsewhere east of 35W, with 5 to 7 ft seas. For the forecast west of 65W, fresh to strong E winds will pulse in the afternoon and evening north of Hispaniola through Fri. Moderate to fresh trades will prevail elsewhere south of 20N. A low along a frontal boundary will sink southward during the weekend off the NE Florida coast. Environmental conditions are forecast to be marginally conducive for some gradual development over the weekend and into early next week while the system drifts slowly offshore of the southeastern United States. Regardless of development, showers and thunderstorms and moderate to fresh winds can be expected over the weekend off the Florida coast. $$ Torres