000 AXNT20 KNHC 220555 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 0605 UTC Sun Sep 22 2024 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 Heavy Rainfall in Central America: A Central American Gyre (CAG) is gradually developing over Central America with a 1007 mb low pressure embedded along the monsoon trough near central Panama. Scattered showers and isolated strong thunderstorms are occurring at the southwestern Caribbean Sea near this low. Starting early next week, it will slowly drift northwestward across northern Costa Rica, Nicaragua, Honduras, and the Yucatan Peninsula through the middle of next week. Aided by abundant tropical moisture, this system may produce significant rainfall near Panama through this weekend, then Costa Rica and eastern Nicaragua Sunday through Tuesday. Afterward, heavy rain may spread over central and northern Guatemala, western Honduras, Belize and the eastern Yucatan Peninsula Monday through Thursday. This will lead to an increased potential for life- threatening flash flooding and mudslides in these areas. It is recommended that residents in the aforementioned areas stay alert on the latest information from their local meteorological agencies. Please refer to the Tropical Weather Discussion for the Eastern Pacific at website: https://www.hurricanes.gov/text/MIATWDEP.shtml for rainfall across El Salvador and the Pacific coasts of Nicaragua, Guatemala, and southern Mexico. ...MONSOON TROUGH/ITCZ... A monsoon trough enters the Atlantic along the coastal border of Senegal and Guinea-Bissau, then extends southwestward across 10N28W to 08N35W. An ITCZ curves northwestward from 08N35W to 10N49W. Scattered moderate convection is seen near the trough from 11N to 15N near the Africa coast. Similar convection is also present up to 70 nm south of the ITCZ between 38W and 42W, and from 08N to 11N between 44W and 50W. The eastern end of the East Pacific monsoon trough is triggering numerous heavy showers and scattered strong thunderstorms offshore the border of Colombia and Venezuela. ...GULF OF MEXICO... A modest surface ridge runs southwestward from near the Florida Panhandle to near Tampico, Mexico. Part of a pronounced upper- level trough stretching southwestward from southern Florida to the northern Yucatan Peninsula is producing widely scattered showers and thunderstorms across the Florida Strait. Gentle ENE to E winds and seas of 1 to 2 ft are present at the southeastern Gulf and western Bay of Campeche. Gentle to moderate E to SE winds and 2 to 4 ft seas prevail for the rest of the Gulf. For the forecast, the ridge will dominate the Gulf into early next week. A broad area of low pressure is forecast to form over the northwestern Caribbean Sea and the adjacent portions of Central America during the next few days. Thereafter, gradual development of this system is likely, and a tropical depression could form as the system moves slowly northwestward across the northwestern Caribbean Sea and Gulf of Mexico through the end of next week. There is a high chance of tropical cyclone formation in the next seven days. Regardless of development, winds and seas will start increasing across the southeastern Gulf early next week. ...CARIBBEAN SEA... Please refer to the SPECIAL FEATURES section above for potential heavy rainfall associated with a developing Central American Gyre (CAG). Convergent surface winds are coupling with strong divergent flow aloft to trigger numerous moderate to isolated strong convection near and south of Jamaica. Scattered moderate convection is noted farther north near the Cayman Islands and Cuba, including the Yucatan Channel and Windward Passage. Refer to the Monsoon Trough/ITCZ section for additional convection in the Caribbean Sea. Moderate to locally fresh E to SE winds and seas of 3 to 5 ft are note at the southeastern basin. Mainly moderate E to ESE winds with 1 to 3 ft seas are found at the Gulf of Honduras. Gentle E to SE to SW winds and seas at 1 to 3 ft exist across the southwestern basin. Gentle to moderate E to SE winds and seas of 2 to 4 ft prevail elsewhere in the Caribbean Sea. For the forecast, moderate to fresh winds and moderate seas are expected across the eastern and central basin through tonight. A broad area of low pressure is forecast to form over the northwestern Caribbean Sea and the adjacent portions of Central America during the next few days. Thereafter, gradual development of this system is likely, and a tropical depression could form as the system moves slowly northwestward across the northwestern Caribbean Sea and Gulf of Mexico through the end of next week. There is a high chance of tropical cyclone formation in the next seven days. ...ATLANTIC OCEAN... A pronounced upper-level trough extends southwestward from the northwestern Atlantic across 31N74W to beyond southern Florida. Strong divergent winds related to this feature are inducing widely scattered moderate convection from 22N to 29N between 60W and 73W. At the central Atlantic, a surface trough meanders eastward from 24N62W through a 1007 mb low near 26N56W to 23N44W, then turns northeastward through another 1006 mb low near 26N42W to 31N40W. Scattered moderate convection is found near the first low with 60 nm of 28N55W, and the second low from 20N to 27N between 39W and 42W. A mid-level trough near 40W is causing scattered moderate convection from 11N to 17N between 41W and 45W. Convergent trade winds are generating similar conditions west of the Cabo Verde Islands from 13N to 17N between 29W and 34W. Refer to the Monsoon Trough/ITCZ section for additional convection in the Atlantic Basin. Moderate to fresh E to SE winds and seas of 6 to 8 ft are evident near the aforementioned low pressure systems from 26N to 29N between 52W and 59W, and north of 24N between 35W and 43W. Otherwise, gentle to locally moderate NE to SE winds with 4 to 6 ft seas are present north of 24N between 30W and the Florida- Georgia coast. To the south from 15N to 24N between 30W and Bahamas/Leeward Islands, light to gentle winds with seas at 2 to 4 ft exist. Farther south from the Equator to 15N between 35W and the Windward Islands/South America coast, gentle to moderate E to SSE winds and seas of 4 to 6 ft in mixed moderate swells are found. Near the Canary Islands, moderate to fresh NNE to NE winds and 5 to 7 ft seas dominate north of 18N between the northwest Africa coast and 30W. Near the Cabo Verde Islands from 12N to 18N between the central Africa coast and 30W, gentle to moderate NNE to NE winds and seas at 2 to 4 ft are found. Light to gentle southerly and monsoonal westerly winds with 4 to 7 ft seas in mixed moderate swells prevail for the remainder of the Atlantic Basin. For the forecast W of 55W, a weak cold front will move off the southeast coast of the US Sunday, then slowly move across the waters north of 25N into Mon night. $$ Chan