000 AXNT20 KNHC 200559 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 0605 UTC Sat Aug 20 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 0000 UTC surface analysis and satellite imagery through 0500 UTC. ...SPECIAL FEATURES... Potential Tropical Cyclone Four is centered near 21.8N 95.2W at 20/0300 UTC or 270 nm SSE of the mouth of The Rio Grande River and moving NW at 12 kt. Estimated minimum central pressure is 1009 mb. Maximum sustained winds are 30 kt with gusts to 40 kt, and seas are peaking at 7 to 10 ft just north and northeast of the center. Scattered showers and thunderstorms are flaring up near and east of the center, and near Vera Cruz, Mexico. Some strengthening is expected and this disturbance should become a tropical storm on Saturday. On the forecast track, the disturbance is expected to approach the coast of northeastern Mexico through Saturday afternoon and make landfall there on Saturday night. This disturbance will likely produce heavy rain at the northeast corner of Mexico and southern Texas from late Saturday afternoon through Saturday night, which might cause mudslides in mountainous areas and flash flooding elsewhere. The combination of storm surge and rising tide will cause coastal inundation. Swells generated by this system are forecast to affect eastern Mexico and southern Texas through this weekend, generating life-threatening surf and rip current conditions. Please consult products from your local weather office. Please, read the latest HIGH SEAS FORECAST issued by the National Hurricane Center at website https://www.nhc.noaa.gov/text/MIAHSFAT2.shtml and the latest Potential Tropical Cyclone Four NHC Forecast/Advisory and Public Advisory at www.hurricanes.gov for more details. ...TROPICAL WAVES... An eastern Atlantic tropical wave is near 29W from northwest of the Cabo Verde Islands at 19N southward, and moving west at 10 to 15 kt. Scattered moderate convection is noted from 05N to 11N between 27W and 32W. An eastern Caribbean tropical wave is near 65W from 21N southward across Puerto Rico into eastern Venezuela, and moving west at 20 to 25 kt. Scattered showers and isolated thunderstorms are occurring over Venezuela, scattered showers are seen near and north of Puerto Rico/Virgin Islands. ...MONSOON TROUGH/ITCZ... A monsoon trough enters the Atlantic through the coast just north of the Mauritania-Senegal border, passing southwest of the Cabo Verde Islands at 11N26W to northeast of French Guiana near 09N48W. Other than convection associated with a nearby tropical wave, scattered moderate convection is seen up to 150 nm south and up to 100 nm north of the trough. Numerous showers are present farther south near the coast of Guinea-Bissau, Guinea and Sierra Leone. No ITCZ is present based on the latest analysis. ...GULF OF MEXICO... Please see the Special Features section for more details on Potential Tropical Cyclone Four. A modest surface ridge reaches westward from central Florida to near Brownsville, Texas. It is sustaining light to gentle winds and seas at 1 to 2 ft over the northeastern and east- central Gulf. Outside the influence of Potential Tropical Cyclone Four, gentle to moderate with locally fresh E to SE winds and 2 to 4 ft seas prevail for the rest of the Gulf. For the forecast, Potential Tropical Cyclone Four will move to 23.2N 96.3W Sat morning, 25.1N 97.6W Sat evening, inland to 26.9N 99.1W Sun morning, and dissipate Sun evening. Heavy rains and tstms are expected over the SW and far NW Gulf over the weekend. ...CARIBBEAN SEA... Aided by an upper-level trough in the vicinity, convergent trades are triggering scattered showers and isolated thunderstorms near and south of the Yucatan Channel, and from the Cayman Islands eastward to near Haiti. Refer to the Tropical Waves section for additional weather in the basin. The Atlantic ridge associated with a 1028 mb Azores High continues to channel NE to E trades across the entire basin. Fresh to strong NE to ENE winds and seas of 6 to 8 ft are evident for the south- central basin, just north of Colombia. Gentle to moderate ENE to E winds and 2 to 4 ft seas are found over the northwestern and extreme southwestern basin. Moderate to fresh ENE to E winds and seas at 4 to 6 ft prevail for the remainder of the basin, including the Gulf of Honduras. For the forecast, the passage of a tropical wave currently at the eastern basin along with the Atlantic ridge will continue to support moderate to fresh trade winds in the eastern and central Caribbean, and fresh to strong winds in the south-central and portions of the SW Caribbean through Sat. Fresh to strong NE winds are also expected across the Windward Passage tonight and Sat night. The ridge will weaken Sun night through Tue, diminishing the winds across the region to gentle to moderate. ...ATLANTIC OCEAN... A surface trough is causing isolated thunderstorms near and just east of the Lesser Antilles. A robust upper-level low at the north-central Atlantic near 30N48W is triggering scattered showers and thunderstorms north of 27N between 46W and 50W. Refer to the Monsoon Trough/ITCZ and Tropical Waves sections for additional weather in the Atlantic Basin. The Atlantic ridge related to the 1028 mb Azores High is supporting light to gentle winds and seas at 2 to 4 ft north of 26N between 50W and the Georgia/Florida coast. Farther south and east, gentle to moderate NNE to ENE trades and 4 to 6 ft seas are evident from 10N to 26N between 30W and the Bahamas/Lesser Antilles, and north of 25N between the African coast and 50W. Gentle to moderate monsoonal and southerly winds with 5 to 8 ft seas in southerly swell prevail for the rest of the Atlantic Basin. For the forecast W of 55W, the Atlantic ridge together with a tropical wave crossing the eastern and central Caribbean will support moderate to fresh easterly winds south of 25N through the weekend. Locally strong winds are likely north of Hispaniola and the approaches to the Windward Passage tonight and Sat night. The ridge will weaken Sun evening into early next week, thus diminishing these winds to gentle to moderate. $$ Chan