000 AXNT20 KNHC 131035 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1205 UTC Sat Aug 13 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 1020 UTC. ...TROPICAL WAVES... A tropical wave is analyzed with axis along 21W from 05N-20N, moving W at 10 kt. A 1009 mb low pressure is near the wave axis at 14.5N19.5W. Scattered moderate to strong convection is noted from 13N-18.5N between 22W and the west coast of Africa, and from 08N-11N between 17W and the west coast of Africa. A tropical wave extends its axis along 54-55W from 24N southward, moving W at 15-20 kt. A broad surface trough is associated with this tropical wave. A large plume of atmospheric moisture accompanies this wave between 48W and 57W, as noted in Precipitable Water imagery, while Saharan Air dominates the environment between 57w and 62W. Scattered moderate isolated strong convection is noted from 08.5N to 15N between 48W and 56W. A weak tropical wave has an axis over the eastern Caribbean along 63-64W from 17N southward to SE Venezuela, moving W at 15 kt. Widely scattered moderate convection is noted from 10N-12.5N between 58W-62W. Saharan Air has engulfed much of this wave and extends from 57W to 69W. A central Caribbean tropical wave has an axis along 77-78W from Jamaica to western Colombia, moving W at 10-15 kt. Isolated moderate convection is over the waters of Haiti, eastern Cuba and Jamaica. Father south, scattered moderate to strong convection is noted from 11.5N southward over northwestern Colombia between 75W-79W. ...MONSOON TROUGH/ITCZ... The monsoon trough extends from the coast of southern Mauritania near 17N16.5W to a 1009 mb low near 14.5N19.5W to 11N25W to 14N46W to 11N56W. The ITCZ continues from 11N56W to the coast of Brazil near 10N62W. Aside from the convection described in the Tropical Waves section above, scattered moderate isolated strong convection is noted within 240 nm S of the trough between 24W-38W. GULF OF MEXICO... A surface trough of low pressure extends over the northwest Gulf of Mexico from SE Louisiana to 27N97W. Low to middle level cyclonic turning across the NW Gulf continues to produce moisture convergence. The coverage of showers and thunderstorms has again tonight compared to the daytime on Friday. Widely scattered moderate convection is noted across the NW Gulf, from 23N northward to 29N and between 91.5W and the coasts of Texas and northeast Mexico. Elsewhere a 1017 mb high pressure is centered over the NE Gulf near 29N86W. Gentle winds prevail across the eastern Gulf, while moderate to locally fresh winds prevail near the surface trough and over the Bay of Campeche. Recent buoy and altimeter data across the basin are showing seas of 2 to 3 ft. However, seas up to 4 ft may be occurring just east of the surface trough in the northwest Gulf, and to the west of the Yucatan Peninsula. For the forecast, low pressure is likely to reform along the surface trough in the NW Gulf later today. This system will drift west-southwestward and approach the Texas coast this afternoon, and move inland over southern Texas on Sun. This system is expected to produce scattered to numerous showers and thunderstorms today through tonight over the northwest Gulf. Strong gusty winds and rough seas can be expected with this activity. Moderate NE to E winds will pulse to fresh during the late afternoon and evenings off the NW Yucatan peninsula through early next week. Meanwhile, a weak frontal boundary is expected to stall just north of the central and NE Gulf through Sun. CARIBBEAN SEA... Satellite imagery shows scattered showers and isolated thunderstorms near Haiti, Jamaica, and Cuba due to the influences of upper-level troughing and a tropical wave in the area, and . also offshore of the NE coasts of Nicaragua and Honduras. That tropical wave is also producing convection near the coasts of Colombia and NW Venezuela, described above in the tropical waves section. Earlier ASCAT satellite wind data showed fresh trade winds in the south- central Caribbean, south of 15N between 67W- 71W, where seas are 4-6 ft. Moderate trades prevail elsewhere east of 76W with 4-5 ft seas. Gentle to moderate winds prevail west of 76W with 2-5 ft seas. The Atlantic high pressure ridge along 29-30N will drift southward and weaken through early next week. Moderate to fresh trade winds over the central Caribbean will weaken to moderate Sat afternoon through Mon, then increase to fresh late Mon through Wed. A broad surface trough accompanying a tropical wave entering the Tropical N Atlantic waters this morning, will move across the Lesser Antilles this evening, across the eastern Caribbean early Sun through early Mon, then across the central Caribbean Mon through late Wed. Trade winds will strengthen late Tue through Wed as high pressure repositions near 27N65W. ATLANTIC OCEAN... Refer to the section above for details on the tropical waves moving across the basin. A surface ridge axis extends from 1024 mb high pressure near 31N42W to 32N57W to 1017 mb high pressure in the NE Gulf near 29N86W. Earlier ASCAT satellite wind data showed gentle anticyclonic winds along and within 300 nm S of the ridge axis, including over the NW Bahamas. Seas are likely near 3 ft in this area, west of 60W. Mid- to upper-level troughing is occurring over most of the area where the surface ridge is. As a result, scattered moderate convection is noted from 26N-33N between 42W- 55W. Scattered clusters of moderate to strong convection extends north of a lone from 27.5N80.5W east-northeastward to beyond 31N69W. Isolated showers and tstorms are also noted across the southern Bahamas. Moderate trades prevail south of 23N to the north of Hispaniola and over the southeastern Bahamas, where seas are 3-5 ft. The broad 1009 mb low along the monsoon trough near 14.5N19.5W is accompanied by moderate winds. However, recent ASCAT satellite wind data showed fresh to locally strong SW winds to the south from 05N-11.5N between 15W-23W. Fresh NE winds are occurring to the north, covering the area between the Cabo Verde Islands and the Canary Islands. Altimeters passing over the area have measured seas of 7 to 8 during the past 6 to 12 hours, from 15N-22N between 30W and the coast of Africa. Moderate to fresh trades and 5-7 ft seas prevail from 14N-24N between 30W-60W. For the forecast W of 55W, the western Atlantic ridge will weaken and sink southward through early next week as a frontal boundary moving off the SE U.S coast stalls just N of the area. Moderate to fresh E winds S of 24N will veer to the SE and weaken to gentle to moderate today and change little through Wed. A broad tropical wave will enter the southeast forecast waters today, bringing a slight increase in winds and seas over those waters tonight through early Mon. A cold front will move over the waters northeast of NE Florida late Tue, then stall and weaken through Wed night. $$ Stripling