000 AXNT20 KNHC 161734 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1805 UTC Wed Aug 16 2023 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 1200 UTC surface analysis and satellite imagery through 1500 UTC. ...TROPICAL WAVES... The axis of a tropical wave is approaching the Cabo Verde Islands along 22W, from 17N southward, moving W at 15 kt. The axis of a tropical wave is just off the coast of Africa near 17W from 18N southward, moving W at 10-15 kt. Scattered moderate and isolated strong convection is noted from 10N to 17N E of 24W. This system is forecast to move toward the west-northwest, with an area of low pressure forming in a day or two just west of the Cabo Verde Islands. Further development of the low is possible over the weekend before environmental conditions become unfavorable early next week. An axis of a tropical wave is in the central Atlantic along 40W, from 18N southward, moving W at 15 kt. Low pressure has developed in association with this wave where it interacts with the monsoon trough. This 1009 mb low pressure is now centered behind the wave axis, near 11N34W. Scattered moderate and isolated strong convection is noted from 07N to 14N between 33W and 43W. Environmental conditions appear conducive for gradual development of this elongated low, and a tropical depression may form during the next several days while the system moves WNW at 10 to 15 kt in the central Tropical Atlantic. The axis of a tropical wave is in the E Caribbean near 64W, from 18N southward, moving W at 15 kt. Convection previously associated with this wave has generally diminished today. The axis of a tropical wave is moving across Central America near 88W, from the Gulf of Honduras southward into the east Pacific, moving W at 15 kt. Convection with this wave is now confined W of the area over Central America and the eastern Pacific. ...MONSOON TROUGH/ITCZ... The monsoon trough passes near coastal Dakar near 15N17W to 14N25W to 12N42W to 12N49W. The ITCZ continues from 12N49W to 11N61W. Scattered moderate and isolated strong convection is noted from 07N to 14N between 24W and 33W. GULF OF MEXICO... The diurnal surface trough moving west through the Bay of Campeche has generally diminished today, but scattered moderate convection lingers over the western Bay of Campeche. Otherwise, a stationary front is noted just inland of the northern Gulf coast, with a weak pre-frontal trough noted along 29N from offshore the Florida Panhandle to the offshore Texas. Scattered moderate convection exists within about 60 nm either side of the trough. Despite these features, weak high pressure dominates the basin, providing light and variable winds and seas of 1 to 2 ft. For the forecast, the surface trough will continue to support isolated thunderstorms across the N Gulf today and tonight. A surface ridge over the central Gulf will support mostly gentle to moderate winds and slight seas across the basin through Sun. CARIBBEAN SEA... Scattered moderate convection is noted near the Windward Islands, otherwise dry conditions prevail. Fresh trades are noted in the central Caribbean, with moderate winds elsewhere, except gentle winds in the NW basin and S of the eastearn extension of the East Pacific monsoon trough along 10N in the far SW Caribbean. Seas are 5 to 7 ft in the central Caribbean, and 3 to 5 ft elsewhere, lesser in the lee of Cuba. For the forecast, fresh to locally strong tradewinds will prevail across the central Caribbean today. The pressure gradient between the Bermuda High and the Colombian Low will loosen tonight, resulting in a slight decrease in winds over the area for the next few days. Gentle to moderate trades and seas will prevail elsewhere. ATLANTIC OCEAN... The dominating feature in the basin is the Bermuda to Azores ridge. This is leading to mainly gentle E winds N of 25N, with the gradient between the ridge and the ITCZ and monsoon trough leading to moderate to fresh trades S of 25N. Some moderate to fresh SW winds are occuring N of the Bahamas, as an eastward moving front along the Mid-Atlantic U.S. coast passes N of the waters. Scattered moderate convection is also noted in this region. Some fresh to locally strong winds have developed within about 100 nm of the center of a 1009 mb low pressure to the SW of the Cabo Verde Islands, that is depicted in more detail in the tropical waves section above. Other convection associated with the monsoon trough and tropical waves is also described in the section above. Seas across the basin are mainly 5 to 8 ft, with areas NW of a 31N60W to Turks and Caicos line having somewhat lower seas of 3 to 5 ft. For the forecast W of 55W, fresh to locally strong tradewinds will pulse off Hispaniola each evening through the weekend. Fresh tradewinds will develop south of 25N starting Thu and diminishing again on Sat. A cold front will approach the NW waters then stall, but fresh SW winds can be expected Thu through Fri morning in the NW waters. Gentle to moderate winds will prevail elsewhere. $$ KONARIK