000 AXNT20 KNHC 230617 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 0605 UTC Mon Sep 23 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), a broad 1006 mb low just offshore from the coastal border of Honduras and Nicaragua is gradually strengthening. Numerous moderate to scattered strong convection is evident across eastern half of the circulation from 13N to near Jamaica between 75W and 82W. Fresh to strong E to SSE winds and seas of 4 to 7 ft are present in this area. Moderate to fresh ENE to E winds and seas of 3 to 5 ft are noted south of Cuba and near the Cayman Islands. Environmental conditions appear conducive for development of this disturbance, and a tropical depression or tropical storm is likely to form during the next few days while the system moves northward across the northwestern Caribbean Sea and into the southeastern Gulf of Mexico. Regardless of development, this system is expected to produce heavy rainfall across the eastern parts of Nicaragua, Honduras and the Yucatan Peninsula through Wednesday, and near eastern Cuba and the Cayman Islands through Thursday. This will greatly increase the potential for life-threatening flashing flooding and mudslides in these regions. 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: www.hurricanes.gov/text/MIATWDEP.shtml for rainfall across El Salvador and the Pacific coasts of Nicaragua, Guatemala, and southern Mexico. ...TROPICAL WAVES... A eastern tropical wave is near 20W from 18W southward and is moving west around 10 kt.Widely scattered moderate convection is depicted from 11N to 15N between the central Africa coast and 23W. Environmental conditions could support some gradual development of this system, and a tropical depression could form during the middle to latter part of the week while it moves westward to west-northwestward across the eastern and central tropical Atlantic. A central Atlantic tropical wave is near 44W from 17N southward and moving west at 5 to 10 kt. Scattered moderate convection is seen from 11N to 18 between 45W and 49W. ...MONSOON TROUGH/ITCZ... A monsoon trough enters the Atlantic along the northern Senegal coast, then cures southwestward through 09N20W to 05N32W. An ITCZ continues westward from 05N32W to 06N43W, then resumes from 10N45W to 10N57W. Widely scattered moderate convection is present south of the trough but near the ITCZ from 03N to 06N between 14W and 41W, and up to 50 nm along either side of the second ITCZ segment. The eastern end of the East Pacific monsoon trough is triggering scattered heavy showers and strong thunderstorms near the Colombia-Venezuela coastal border in the south-central Caribbean Sea. ...GULF OF MEXICO... See Special Features section about possible tropical system development in the southeastern Gulf. A modest surface ridge runs southwestward from a 1013 mb high at the northeastern Gulf to near Veracruz, Mexico. Gentle to moderate ENE to SE winds and seas of 2 to 4 ft prevail for the entire Gulf. For the forecast, as the low pressure mentioned in the Special Features section moves into the southeastern Gulf, winds and seas will significantly increase across the eastern Gulf this week. There is a medium chance of tropical formation within the next 48 hours and a high chance over the next 7 days. ...CARIBBEAN SEA... Please refer to the Special Features section above for potential heavy rainfall associated with a Central American Gyre (CAG) over the western basin. Refer to the Special Features and Monsoon Trough/ITCZ sections for convection in the Caribbean Sea. Outside the winds and seas mentioned in the Special Features section, gentle to moderate E to SSE winds and seas at 2 to 4 ft prevail in the basin. For the forecast, heavy rain and increasing winds and seas are expected across portions of the northwestern basin early this week. There is a medium chance of tropical formation within the next 48 hours and a high chance over the next 7 days. ...ATLANTIC OCEAN... A cold front curves southwestward from northeast of Bermuda across 31N65W to just north of the northwest Bahamas. isolated thunderstorms are occurring up to 40 nm along either side of this feature. Scattered moderate convection is seen north of 29N between 54W and 56W, near a 1008 mb low at 28N56W. A surface trough near 15N36W is causing scattered moderate convection from 13N to 17N between 35W and 40W. Refer to the Tropical Waves and Monsoon Trough/ITCZ sections for additional convection in the Atlantic Basin. Moderate to locally fresh SE Winds and seas of 5 to 7 ft are evident north of 24N between 35W and 55W. Gentle to moderate N to NE winds and 4 to 6 ft seas are found near and behind the cold front. Otherwise, light to gentle winds and seas of 2 to 4 ft dominate north of 20N between 35W and the Florida-Georgia coast. For the tropical Atlantic from 05N to 20W between 35W and the Lesser Antilles, light to gentle with locally moderate NE to SE winds and 3 to 5 ft seas are present. Gentle to moderate southerly and monsoonal westerly winds with 4 to 7 ft seas in mixed moderate swells prevail for the remainder of the Atlantic Basin west of 35W. For the forecast W of 55W, a set of northerly swell will propagate into the northern waters Mon, bringing an increase in seas over the waters north of 30N through the middle of the week. Low pressure is forecast to move northward through the eastern Gulf of Mexico late this week, which may bringing increasing winds and seas to areas offshore Florida and north of the Bahamas. $$ Chan