000 AXNT20 KNHC 251133 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1205 UTC Thu Aug 25 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 0600 UTC surface analysis and satellite imagery through 1115 UTC. ...TROPICAL WAVES... A far eastern Atlantic tropical wave has its axis just offshore Africa along 18W from 05N to 21N moving westward at 10 kt. The surrounding environment of this wave has moistened up since 24 hours. Scattered moderate to isolated strong convection is noted from 10N to 14N between 18W-22W. Scattered moderate convection is from 08N to 11N between 14W-22W. Convective activity preceding this wave consists of a large cluster numerous moderate to strong convection from 06N to 13N between 26W-32W, and of scattered moderate to isolated strong convection from 04N to 08N between 32W-38W. This activity has been rather persistent, and appears to be a piece of energy that had detached from the wave when it was inland Africa yesterday. Environmental conditions could support some slow development of this system later this week, or during the weekend as it continues on westward. A central Atlantic tropical wave has its axis along 43W from 02N to 20N moving westward at 10 kt. Deep convection continues to be limited due to a dry and stable surrounding environment. Only isolated showers and thunderstorms are seen within 180 nm west and 120 nm east of the wave axis from 14N to 17N. A western Atlantic tropical wave has its axis approaching 60W from 03N to 20N moving westward around 5 kt. Surface observations from Barbados during the overnight hours have been indicating light to heavy showers, with thunderstorms at times. In addition, eastern Caribbean radar composites show scattered showers and thunderstorms now spreading into the southeastern Caribbean within about 180 nm west of the wave. Surface observations from other Windward Islands are reporting similar type of weather. Scattered showers and thunderstorms are also located east of the wave from 10N to 15N between the wave and 55W. Environmental conditions could become more conductive for slow development of this system in several days after it crosses the Windward Islands and moves across the eastern and central Caribbean Sea late this week and into early next week. A tropical wave has its axis inland the Yucatan Peninsula along 91W south of 20N to the eastern Pacific Ocean. It is moving westward at about 5 kt. Scattered moderate to isolated strong convection is over and just offshore Belize, while scattered showers and thunderstorms are just north of the Gulf of Honduras. ...MONSOON TROUGH/ITCZ... The monsoon trough axis extends from the coast of Mauritania near 20N16W southwestward to 14N30W, then to 12N50W and to the coast of Venezuela near 09N61W. Outside of convection associated to tropical waves, scattered moderate convection is within 60 nm north of the trough between 37W-39W. GULF OF MEXICO... Weak high pressure is across the area. The associated light gradient is maintaining generally light to gentle east-southeast winds over the Gulf, except for moderate to fresh northeast to east winds near and to the west of the Yucatan Peninsula in the eastern Bay of Campeche. Marine conditions are quite favorable as seas are relatively low throughout the Gulf, in the 1-3 ft range, except for slighter higher seas of 3-4 ft in the central and eastern Bay of Campeche, and in the central and west-central sections of the Gulf. Scattered showers and isolated thunderstorms are observed along the northern Gulf waters due to a stationary boundary along the coast. Isolated showers and thunderstorms are elsewhere over the Gulf. For the forecast, the weak high pressure will remain over the area through the forecast period maintaining gentle to moderate winds and slight seas. The moderate to fresh northeast to east near and to the west of the Yucatan peninsula in the eastern Bay of Campeche will pulse due to local effects during the late afternoons and at night through the forecast period. CARIBBEAN SEA... The pressure gradient between weak high pressure over the western Atlantic and relatively lower pressure in the southwestern Caribbean is allowing for moderate to fresh trade winds across the eastern and central Caribbean with 3-5 ft seas. Elsewhere winds are gentle to moderate along with 1-3 ft seas. Deep-layer moisture over the western and central Caribbean is supporting scattered showers and thunderstorms across just about the entire western Caribbean and over the central Caribbean north of about 16N. Similar activity is along and just offshore the coast of central and eastern Cuba, and over the southern part of the Windward Passage. For the forecast, high pressure over the central Atlantic will continue to support moderate to fresh trade winds in the eastern and central Caribbean through the forecast period, while gentle to moderate winds will continue across the western Caribbean. A tropical wave accompanied by scattered showers and thunderstorms is approaching the Windward Islands. The wave will move across the Lesser Antilles tonight, the eastern Caribbean Fri through Sat night and the central Caribbean into early next week, with potential for slow development. ATLANTIC OCEAN... High pressure remains the dominant feature across the subtropical Atlantic. A surface trough extends from near 30N72W to 27N73W and to the central Bahamas. An area of numerous moderate convection is evident to its east from 25N to 30N between the trough and 67W. This activity is quickly increasing. Moderate to fresh southeast to south winds are east of the trough to near 65W, while light to gentle winds are to its west. Seas west of the trough are in the 2-4 ft range, while east of the trough they are in the 4-6 ft range. Generally, gentle to moderate easterly winds along with seas of 4-6 ft are elsewhere over the area. In the central Atlantic, a stationary frontal boundary extends from a weak 1018 mb low that is centered near 32N40W to 29N51W. An overnight ASCAT data pass indicated gentle to moderate northeast winds behind the front and gentle winds south of the front. Seas are 3-5 ft north of 25N. A 102 mb high center is analyzed to the south of the stationary front near 27N44W. Trade winds increase to moderate speeds south of 25N along with 4-6 ft seas. A tight pressure gradient due to the combination of strong high pressure centered well north of the area and broad low pressure over northern Africa is resulting in fresh to strong northeast winds and 6-9 ft seas from 20N to 31N between the coast of Africa and 24W. Fresh southwest winds, as noted in overnight ASCAT data passes over the far eastern Atlantic, are feeding into the convection associated to the tropical wave that is along 18W. These winds extend south to near 04N. For the forecast west of 55W, the aforementioned surface trough will continue to slowly move westward through Fri while it weakens. Scattered showers and thunderstorms will be mainly east of the trough. Otherwise, weak high pressure will build in the wake of the trough through the next few days. The associated gradient should allow for gentle to moderate east to southeast winds over the area through the weekend and into early next week, except for moderate to fresh winds between the southeastern Bahamas and Hispaniola. Scattered showers and thunderstorms are expected over the NW forecast waters during the weekend as a front stalls across north- central Florida and extends northeastward over those waters. Winds and seas may be higher in and near scattered showers and thunderstorms. $$ Aguirre