000 AXNT20 KNHC 241107 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1205 UTC Wed Aug 24 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 1045 UTC. ...TROPICAL WAVES... A central Atlantic tropical wave has its axis along 38W from 03N to 20N moving westward at 10 kt. Scattered moderate convection is within 180 nm west of the wave from 14N to 17N. Otherwise, the environment surrounding this wave remains rather dry limiting deep convection from forming. A western Atlantic tropical wave has its axis along 57.5W from 03N to 20N moving westward at 5 kt. This wave is part of a broad trough of low pressure that is east of the Windward Islands. Scattered moderate to isolated strong convection is within 120 nm west of the wave from 06N to 09N. Scattered moderate convection is within 150 nm east of the wave from 06N to 09N. Scattered showers and isolated thunderstorms are within 150 nm east of the wave from 11N to 13N. Environmental conditions could become more conducive for slow development of this system in several days while it is forecast to move across the Windward Islands and into the southeastern Caribbean Sea. A western Caribbean tropical wave has its axis along 87W south of 20N moving westward at about 10 kt. Scattered showers and thunderstorms are lagging behind the wave from 15N to 18N between 79W-83W. Isolated showers and thunderstorms are elsewhere west of 78W. ...MONSOON TROUGH/ITCZ... The monsoon trough axis extends from the coast of Mauritania near 18N16W southwestward to 14N23W, then to 15N35W to 11N45W and to 09N60W. Increasing numerous moderate to strong convection is south of the trough from 08N to 13N between 20W-26W, and from 06N to 10N between 26W-30W. Scattered moderate convection is within 120 nm south of the trough between 47W-50W. GULF OF MEXICO... The broad base of an upper-level trough is situated just inland the NE and north-central Gulf, while a stationary frontal boundary is analyzed from near 29N85W northwestward to inland southeastern Louisiana. This boundary is serving as the focus for rounds of scattered showers and thunderstorms that form along it and track in an eastward direction. As shortwave troughs move through the upper-level trough, expect for this activity to remain quite active through the next couple of days as the present synoptic pattern changes little. Meanwhile, diffluent flow aloft is supporting isolated showers over the far eastern Gulf waters north of 26N. A surface trough is just along the western section of the Yucatan Peninsula. The earlier noted scattered moderate convection in the Bay of Campeche has diminished to mainly isolated showers. An overnight ASCAT data pass indicated gentle to moderate northeast to east winds across and near this trough, including the eastern Bay of Campeche. Otherwise, relatively weak high pressure remains over the area. The associated gradient is supporting gentle to moderate winds and 1-3 ft seas across the Gulf. For the forecast, relatively weak high pressure will remain over the area through the forecast period 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 Thu. CARIBBEAN SEA... Abundant deep layer moisture is present in the basin. Aside from the shower and thunderstorm that is near the tropical wave along 87W, small clusters of similar activity moving westward is over the central part of the sea from 15N to 17N between 69W-72W, and scattered showers and isolated thunderstorms are over most sections of the eastern Caribbean. Isolated showers and thunderstorms, also moving westward are seen elsewhere across the sea, with the exception of the far southwestern part of the sea where scattered showers and isolated thunderstorms are occurring. Winds are generally gentle to moderate from the east with 2-4 ft seas. 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 moving through the Tropical N Atlantic waters, and was analyzed along 57.5W at 0600 UTC. The wave is expected to reach the Lesser Antilles Wed night, then move through the eastern Caribbean Thu through Fri night and the central Caribbean Sat through Sun night. ATLANTIC OCEAN... The Bermuda-Azores High is the main feature across the Atlantic subtropical waters. The western Atlantic is generally under a gentle to moderate southeast wind flow, with seas in the 3-5 ft range. A surface trough is analyzed from near 30N65W to 25N70W as highlighted in an overnight ASCAT data pass. This pass shows a very noticeable wind shift across the trough axis, with moderate to fresh southeast to south winds east of the trough to near 63W and light to gentle northeast to east winds west of the trough to near 72W. In addition, the trough continues to be underneath a large and persistent upper-level low that is located near 25N68W per latest satellite water vapor imagery. In the central Atlantic, a weakening cold front extends from a weak 1018 mb low north of the area near 37N33W southwestward to 33N41W and to 32N45W, then becomes stationary to 32.5N40W. Scattered moderate convection is near the low pressure, and also from 32N to 35N between 34W-38W. Isolated small showers and thunderstorms are seen from 30N to 32N between 40W-49W, and from 30N to 33N between 53W-56W. All of the activity is moving to the south, except for the activity from 30N to 33N between 53W-56W, which is moving westward. Winds in the central Atlantic mainly moderate and east in direction, except for light to gentle east winds north of 27N between 40W-62W as a 1023 mb high center is north of the area near 33N57W. Seas in this part of the Atlantic are in the 4-6 ft range. The pressure gradient is tighter in the eastern Atlantic, supporting moderate to fresh northeast winds and seas of 6-8 ft. Stronger winds of fresh to strong speeds are along and within about 180 nm northwest of the coast of Africa from 21N to 28N. Seas are also 6-8 ft with these winds. For the forecast W of 55W, the aforementioned surface trough will move westward toward the Bahamas through Thu accompanied by scattered to numerous showers and thunderstorms. Winds and seas may be higher in and near scattered showers and thunderstorms. Relatively weak high pressure will build in the wake of the trough allowing for generally a gentle to moderate east to southeast flow beginning on Wed. 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. $$ Aguirre