000 AXNT20 KNHC 300557 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 0605 UTC Sun Jul 30 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 0000 UTC surface analysis and satellite imagery through 0500 UTC. ...SPECIAL FEATURES... Central Tropical Atlantic (AL96). Disorganized showers and thunderstorms located about 1000 miles east-northeast of the Leeward Islands are associated with a tropical wave and broad area of low pressure. Environmental conditions are forecast to be favorable for gradual development of this system during the next few days, and a tropical depression is likely to form during the early part of the week. The disturbance is expected to move northwestward at about 15 mph during the next day or so, and then turn northward over the central subtropical Atlantic by late Monday or Tuesday. Formation chance through 48 hour is medium. Please visit the latest Tropical Weather Outlook issued by the National Hurricane Center at www.hurricanes.gov for more details. ...TROPICAL WAVES... A tropical wave is being analyzed in the eastern Atlantic near 22W from the equator to 19N, moving westward at 10-15 kt. Scattered moderate convection is observed from 10N to 17N east of 22W, enhanced by the monsoon trough. A Caribbean tropical wave was relocated based on diagnostics and satellite imagery and is now located near 75W from Colombia to 20N. No significant convection is seen in association with this wave. The far northern extent of a tropical wave is over the Bay of Campeche, SE Mexico, and central America located near 94W south of 20N, moving west at 15 kt. Scattered moderate convection is in the Bay of Campeche south of 20N west of 92W. ...MONSOON TROUGH/ITCZ... The monsoon trough extends from the coast of Africa near 14N17W to 09N30W to 17N48W to 14N57W. In addition to the convection in the eastern Atlantic described in the TROPICAL WAVE section, scattered moderate convection is observed from 03N to 10N between 25W and 37W. The eastern extent of the Pacific monsoon trough is supporting scattered showers and thunderstorms in the SW Caribbean along the coast of Panama and Costa Rica. GULF OF MEXICO... Please refer to the TROPICAL WAVES section above for information about the Bay of Campeche tropical wave. Elsewhere, no significant convection is seen in the Gulf. A 1019 mb high pressure is centered near south-west Louisiana. Easterly winds are light to gentle across the majority of the basin, increasing to moderate speeds in the Bay of Campeche. Seas are 1-3 ft in the northern Gulf and 2-4 ft in the southern Gulf. For the forecast, a weak surface ridge will remain the dominant feature across the basin through early next week. This will support gentle to moderate winds, except over the eastern Bay of Campeche, where winds will be enhanced by a thermal trough that will emerge off the Yucatan Peninsula each night. A weak surface trough currently extending across northern Florida and remain the focus for scattered showers and isolated thunderstorms over the far east Gulf waters. High pressure will shift SE into the east central Gulf Tue and Wed and allow for moderate return flow to develop across the W Gulf. CARIBBEAN SEA... Please refer to the TROPICAL WAVES section above for convection in the central Caribbean. Another area of scattered showers and isolated thunderstorms is seen south of western Cuba. This activity is drifting mainly southward as it dissipates. The gradient between the expansive subtropical high and lower pressure over Colombia is supporting enhanced easterly trades winds across the basin. Trades are strong in the south-central Caribbean with 8-10 ft seas, and fresh in the remainder of the central basin with 7-8 ft seas, and moderate to fresh in the eastern and NW Caribbean with 5-7 ft seas. For the forecast, the pressure gradient between the Bermuda High and lower pressure over Colombia will induce pulsing fresh to strong trades across the entire central Caribbean through Mon, then become confined to the south central Caribbean through next week. A strong tropical wave is expected to move across the Tropical Atlantic and reach 60W by late Sun. A broad area of low pressure has developed in the vicinity of the wave and is expected to move NW into the open Atlantic through Wed. ATLANTIC OCEAN... Moderate convection is seen off the coast of north Florida, north of 29N west of 79W in association with a surface trough. For convection elsewhere in the basin please refer to the TROPICAL WAVES and MONSOON TROUGH/ITCZ sections above. The weather pattern is dominated by an expansive subtropical high pressure ridge with its axis oriented E-W along 32N. In the western Atlantic winds are gentle to moderate from the S-SE with 4-6 ft seas. In the central Atlantic, winds are gentle to moderate from the E, with seas generally 4-6 ft in the central Atlantic. Higher winds and seas are near the tropical disturbance. In the eastern Atlantic, the gradient between the subtropical high pressure and lower pressure over Africa is supporting moderate to fresh NE winds and 6-7 ft seas. An area of Saharan Air is observed east of 40W and north of 11N. Lower visibility and hazy skies may be possible within this area. For the forecast west of 55W, high pressure centered over the central Atlantic will gradually shift eastward through Tue, and will maintain moderate to fresh trade winds S of 23N through early Mon. Fresh trades will pulse each late afternoon through evening N of Hispaniola and over the Windward Passage. Developing surface low pressure across the central Atlantic near 20N47W will move NW then N across the NE offshore zones Mon through early Wed before exiting the region to the N. $$ KRV