000 AXNT20 KNHC 301548 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1805 UTC Tue Aug 30 2022 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 1545 UTC. ...SPECIAL FEATURES... A broad 1007 mb area of low pressure along a tropical wave is near 15N48W, moving W at around 5 kt. A large area of disorganized cloudiness and thunderstorms is present with scattered moderate and isolated strong convection noted from 09N to 18N between 41W and 60W. Some gradual development of this system is expected over the next several days and a tropical depression is likely to form later this week. The disturbance is forecast to move slowly toward the west and then west-northwest at 5 to 10 kt, toward the adjacent waters of the northern Leeward Islands. A recent scatterometer pass found an elongated circulation with fresh to strong NE winds over the northern semicircle of the low, with seas likely peaking near 10 ft. The disturbance has a medium chance of tropical cyclone formation through 48 hours, and a high chance of development in the next 5 days. Please read the latest Tropical Weather Outlook issued by the National Hurricane Center at www.hurricanes.gov and the latest High Seas Forecast issued by the National Hurricane Center at https://www.nhc.noaa.gov/text/MIAHSFAT2.shtml for additional marine information. ...TROPICAL WAVES... An eastern Atlantic tropical wave extends along 18W, from 06N to 18N, moving W at around 7 kt. Scattered moderate convection is observed from 06N to 19N, between 16W and 28W. Some gradual development is possible, and the system could become a short- lived tropical depression over the far eastern Atlantic during the next few days. By late this week, the disturbance is forecast to move over cooler waters and further development is not expected. The current outlook assigns a low probability of tropical cyclone development through 48 hours, and a medium chance of development in the next 5 days. Regardless of development, the system could bring locally heavy rainfall to portions of the Cabo Verde Islands by Wednesday. A central Caribbean tropical wave extends along 74W, from 08N to 21N, moving W at 25 kt. An upper-level low centered near the Windward Passage and associated mid-level troughing is enhancing scattered moderate convection west of the wave from 12N to 19N, between 75W and 85W. A central American tropical wave extends along 88W, from 07N to 21N, moving W at 15 kt. Convection is primarily over land, widely isolated and generally weak. ...MONSOON TROUGH/ITCZ... The monsoon trough extends from the coast of Senegal near 16N46W to 10N30W to 15N47W to 09N56W. In addition to the convection associated with the two Atlantic tropical waves, scattered weak convection is observed from 06N to 13N, between 30W and 40W. GULF OF MEXICO... A relaxed pressure gradient is leading to favorable marine conditions across the majority of the Gulf. A surface trough in the NE Gulf is supporting an area of isolated moderate convection from 23N to 30N, between 83W and 87W. Widely isolated thunderstorms are also observed throughout the remainder of the northern half of the basin. Outside of thunderstorms, winds are light to gentle with 1-3 ft seas. For the forecast, high pressure will continue to dominate the weather pattern across the Gulf waters into Fri maintaining gentle to moderate winds and slight seas. Moderate to fresh NE to E winds will pulse near and to the W of the Yucatan peninsula due to local effects during the late afternoons and at night through the forecast period. CARIBBEAN SEA... Refer to the tropical waves section above for details on the convection is the western Caribbean. The gradient between subtropical high pressure and lower pressure over the SW Caribbean is supporting moderate to fresh easterly trade winds across the eastern and central Caribbean, where seas are 3-5 ft. Winds are moderate in the NW Caribbean with 2-4 ft seas and gentle in the SW Caribbean with 2-4 ft seas. For the forecast, a ridge N of the Caribbean Sea will support moderate to fresh trade winds across the central Caribbean, and gentle to moderate winds elsewhere. ATLANTIC OCEAN... A broad area of low pressure over the central tropical Atlantic has a medium chance of tropical cyclone formation within 48 hours. Please see the Special Features section above for more details. In the western Atlantic a line of thunderstorms ahead of a weak cold front is observed from 31N78W to 30N80W. An upper level low over the Windward Passage is supporting another area of scattered thunderstorms NE of the Bahamas from 23N to 26N, between 70W and 75W. A 1019 mb high pressure centered near 29N66W is dominating the pattern in the western Atlantic. Winds are rotating anticyclonically around this feature with gentle to moderate speeds and 3-5 ft seas. In the eastern Atlantic, moderate to fresh NE winds dominate with 5-7 ft seas. Fresh to strong SW winds are noted south of the monsoon trough, between the coast of Africa and 25W, where seas are 8-10 ft. For the forecast west of 55W, a broad and elongated area of low pressure several hundred miles E of the Lesser Antilles is producing a large area of disorganized showers and thunderstorms. Despite only marginally conducive environmental conditions, some gradual development is expected over the next several days and a tropical depression is likely to form later this week. This system is expected to move W and WNW and reach the far SE forecast zones Thu night into Fri. Elsewhere, gentle to moderate winds will prevail across much of the area through the weekend. $$ Flynn