000 AXNT20 KNHC 182305 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 0005 UTC Fri Jul 19 2024 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 2200 UTC. ...TROPICAL WAVE... An Atlantic Ocean tropical wave is along 59W from 21N southward, moving quickly W at 20-25 kt. No significant convection is noted with the tropical wave at this time. A Caribbean Sea tropical wave is along 79W, from just west of Jamaica to central Panama, moving W at 15-20 kt. Scattered moderate convection is from 10N to 12N between 77W and 83W. ...MONSOON TROUGH/ITCZ... The monsoon trough passes through the border of Senegal and The Gambia near 13N17W and continues to 08N45W to 10N55W. Scattered moderate convection is active from 10N to 12N between 20W and 25W. GULF OF MEXICO... A surface trough extends across the northern Gulf from off the western Florida Panhandle to off central Texas. A second weak trough is over the central Bay of Campeche. Elsewhere, high pressure reaches from the western Atlantic to the northeast Gulf. This weak pressure pattern is supporting gentle breezes and slight seas across the basin. An upper trough is supporting a few showers and thunderstorms across the eastern Gulf. For the forecast, high pressure will extend from the western Atlantic into the northern Gulf of Mexico through early next week, supporting mainly gentle winds and slight seas. Unstable atmospheric conditions with periods of active weather will persist across the northern Gulf through Fri as an upper trough continues to the north of the basin. CARIBBEAN SEA... Please see the Tropical Waves section above for details on tropical waves and convection. Recent scatterometer and altimeter satellite data confirmed fresh to strong trade winds and seas to 8 ft south of Jamaica, related to high pressure building over the central Caribbean in the wake of the tropical wave moving into the western Caribbean. A broad area of fresh trade covers the remainder of the central Caribbean, with 5 to 7 ft seas. Gentle to moderate trade winds and 3 to 5 ft seas are noted elsewhere across the basin. For the forecast, the pressure gradient between an Atlantic high pressure ridge extending along roughly 30N and lower pressure across South America is supporting fresh to locally strong trade winds over the central Caribbean, with mainly moderate seas. Winds and seas will diminish slightly tonight through Sat as a pair of tropical waves move through the basin. The tradewinds and associated seas will increase again Sat night into Mon as high pressure builds again in the wake of the tropical waves. ATLANTIC OCEAN... The Bermuda high dominates the tropical Atlantic, characterized by 1028 mb high pressure centered near 32N54W. Recent buoy data and earlier scatterometer satellite data confirmed an area of fresh trade winds between the high pressure and a tropical wave approaching the Lesser Antilles. Seas in this area are 7 to 9 ft. Gentle to moderate trade winds and 5 to 7 ft seas are noted elsewhere across the basin, except for pulses to 25 kt off the north coast of Hispaniola. For the forecast west of 55W, the Bermuda high pressure ridge will extend east to west along roughly 30N through Tue. This pattern will support moderate to fresh easterly winds south of 26N, with winds pulsing to strong during the late afternoon and evening off the northern coast of Hispaniola. $$ Christensen