000 AXNT20 KNHC 120551 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 0605 UTC Mon Sep 12 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 0530 UTC. ...TROPICAL WAVES... An Atlantic Ocean tropical wave is along 40W/41W, from 20N southward, moving westward from 15 knots to 20 knots. Precipitation: widely scattered to scattered moderate, and isolated to widely scattered strong are from 05N to 19N between 30W and 50W. An Atlantic Ocean tropical wave is along 60W/61W, from 21N southward, moving westward 15 knots. Precipitation: isolated moderate is within 120 nm on either side of the tropical wave. ...MONSOON TROUGH/ITCZ... The monsoon trough passes through the coastal plains of Senegal near 15N17W, to 11N22W 14N33W 03N51W. Precipitation: isolated moderate to locally strong is from 04N to 17N between 10W and 30W. A NE-to-SW oriented upper level trough is about 400 nm to the northwest of the part of the monsoon trough that is from 30W eastward. Comparatively drier air in subsidence is apparent in the water vapor imagery. No significant deep convective precipitation accompanies the upper level trough. GULF OF MEXICO... Upper level anticyclonic wind flow with a ridge covers the south central sections of the Gulf of Mexico, including the Yucatan Peninsula. Remaining upper level cyclonic wind flow is just to the north of the ridge, in the central Gulf. A surface trough is in the middle of two areas of surface anticyclonic wind flow, from coastal Alabama, into the center of the Gulf of Mexico, to Guatemala. A surface ridge extends from a 1018 mb 29N77W Atlantic Ocean high pressure center, into the east central Gulf of Mexico. A 1018 mb high pressure center is near 28N95W. Precipitation: isolated to widely scattered moderate, and isolated strong is to the east of the line that runs from southern Louisiana to the northern parts of the Isthmus of Tehuantepec of southern Mexico. The sea heights range from 4 feet to 6 feet in the central one-third of the Gulf of Mexico. The sea heights range from 1 foot to 2 feet elsewhere. Mostly gentle winds are in the area. A surface trough extending from near Mobile, Alabama to 19N91W will linger over the central Gulf into mid week, ahead of a cold front moving into the northern Gulf Mon. The weak cold front will shift slowly south then stall from near Tampa, Florida to Corpus Christi, Texas by mid week then dissipate. CARIBBEAN SEA... An upper level cyclonic circulation is between Andros Island in the Bahamas and NW Cuba. Precipitation: isolated moderate to locally strong is in the rest of the Atlantic Ocean that is from 70W westward, and in the NW Caribbean Sea, the Straits of Florida, and in the SE Gulf of Mexico from 17N northward between Hispaniola and the Yucatan Peninsula. Mostly gentle wind speeds or slower are in the Caribbean Sea. The exceptions are moderate NE winds from 11N to 16N between 72W and 81W, and from 13N southward between 60W and 70W. The sea heights range from 4 feet to 5 feet between 70W and 80W. The sea heights range from 2 feet to 4 feet in the remainder of the area. The monsoon trough is along 11N/12N, from northern Colombia beyond northern Costa Rica, into the eastern Pacific Ocean. Precipitation: isolated moderate is from 16N southward from 70W westward. Mainly moderate E to SE winds prevail across the basin through tonight, except for fresh to locally winds in the south-central Caribbean and offshore eastern Honduras. Gentle to moderate winds and slight to moderate seas will persist Mon into Tue over the Caribbean as a tropical wave moves across the eastern and central portions of the basin. Winds and seas will start to increase from east to west starting late Tue as high pressure builds north of the area in the wake of the tropical wave. Northerly swell will propagate through the Atlantic passages early on Tue and will gradually subside late Wed. ATLANTIC OCEAN... An upper level trough, and its associated cold front/stationary front, are the main weather features for the Atlantic Ocean that is from 20N northward between 48W and 75W. Comparatively drier air in subsidence is apparent in the water vapor imagery from the frontal boundary northward. Precipitation: isolated moderate to locally strong is from 20N northward from 40W westward. An upper level cyclonic circulation center is between Andros Island in the Bahamas and NW Cuba. Precipitation: isolated moderate to locally strong is in the rest of the Atlantic Ocean that is from 70W westward, and in the NW Caribbean Sea, the Straits of Florida, and in the SE Gulf of Mexico from 17N northward between Hispaniola and the Yucatan Peninsula. A surface ridge extends from a 1020 mb high pressure center that is near 29N37W, to 23N52W, to a 1017 mb high pressure center that is near 23N65W, beyond a 1018 mb high pressure center that is near 29N77W. The sea heights range from 8 feet to 12 feet and higher, to the north of line 31N24W 24N47W 23N59W 31N73W. Fresh to strong winds speeds are from 28N northward between 40W and 50W. Strong winds are within 200 nm of the coast of Africa from 18N to 23N. Moderate wind speeds or slower, and sea heights that range from 3 feet to 6 feet, are in the remainder of the Atlantic Ocean. Northeasterly swell of 8 to 12 ft is evident north of a cold front currently reaching along roughly 26N/27N east of 70W. The front will continue to move southward to 24N east of 65W through Mon, then stall and dissipate through late Mon into Tue. The swell will spread across the open waters east of the Bahamas through late Mon, then subside into mid week. Looking ahead, the northern end of a tropical wave will pass 55W south of 22N by Thu, bringing fresh E winds and locally rough seas to the area northeast of the northern Leeward Islands. $$ mt/jl