000 AXNT20 KNHC 242200 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 0005 UTC Wed Aug 25 2021 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 1800 UTC surface analysis and satellite imagery through 2200 UTC. ...SPECIAL FEATURE... Heavy Rainfall in southern Central America: A broad area of low pressure is expected to form over the SW Caribbean Sea later this week, resulting in an increase in moisture and unstable conditions across southern Central America. Heavy rainfall is expected across SE Nicaragua, Costa Rica, Panama, and NW Colombia through early in the weekend. The heaviest precipitation is forecast to affect southern Costa Rica and western Panama late this week. These rains could cause significant flooding and mudslides in some areas. ...TROPICAL WAVES... The axis of a tropical wave is near 28W, south of 19N, moving W at 10 to 15 kt. A 1008 mb low pressure is along the wave axis, where the wave intersects the monsoon trough. Scattered moderate isolates strong convection is noted from 03N to 14N between 27W and 31W. The NHC is tracking this disturbance for possible tropical cyclone development. For more details, please see the latest Tropical Weather Outlook. The axis of a tropical wave is near 48W, south of 18N, moving W at 10 to 15 kt. There is no significant convection associated to this wave. The axis of a tropical wave is near 68W, south of 20N, moving W at 10 to 15 kt. Scattered moderate isolated strong convection is noted from 11N to 18B between 64W and 71W. This disturbance is being monitored for possible tropical cyclone development. For more details, please see the latest Tropical Weather Outlook. ...MONSOON TROUGH/ITCZ... The monsoon trough enters the Atlantic Ocean near 16N17W to 08N34W to 10N49W. The ITCZ then extends from 10N49W to 11N61W. Aside from convection noted in the tropical waves section, scattered moderate isolated strong convection is noted from 02N to 06N between 34W and 38W. ...GULF OF MEXICO... High pressure continues to dominate the weather conditions across the Gulf of Mexico. A surface trough in the northern Gulf extends from the Florida Panhandle to 27N91W. A few showers are noted along the trough. Light to gentle winds are noted over the NE Gulf, with gentle to locally moderate winds elsewhere. Seas are in the 2-3 ft range over the SW Gulf, and 1-2 ft elsewhere. For the forecast, a surface trough will move into the eastern Gulf Wed night into Thu morning, bringing fresh E winds. Otherwise, high pressure pressure will dominate the basin through Fri, producing mainly gentle to moderate E to SE winds. Fresh winds will pulse west of the Yucatan Peninsula tonight and again Wed night. A broad area of low pressure is expected to form Thu over the southwestern Caribbean. Environmental conditions are forecast to be conducive for development if the low remains over water, and a tropical depression could form late this week or this weekend while the system moves northwestward over the northwestern Caribbean Sea, across the Yucatan Peninsula of Mexico, and into the southwestern Gulf of Mexico by Sun. The system has a medium chance of tropical cyclone formation within the next 5 days. Regardless of development, confidence is increasing that winds and waves will increase Sun over the central and SW Gulf of Mexico. ...CARIBBEAN SEA... Fresh to strong winds prevail over the waters south of 15N and east of 79W. Fresh to strong winds are over the windward passage. Moderate to fresh winds are noted elsewhere. Seas are in the 6-8 ft range over much of the waters between 64W and 80W and over the windward passage. Seas are in the 3-4 ft range over the NE Caribbean, and 4-6 ft elsewhere. For the forecast, fresh to locally strong trade winds will dominate most of east and central Caribbean through midweek with seas in the 7 to 9 ft range. Fresh to strong winds are also expected in the Windward passage and in the lee of Cuba through tonight. A broad area of low pressure is expected to form over the southwestern Caribbean by Thu. Environmental conditions are forecast to be conducive for development if the low remains over water, and a tropical depression could form late this week while the system moves northwestward over the northwestern Caribbean Sea. The disturbance should reach the Yucatan Peninsula Sat and be in the southwestern Gulf of Mexico by Sun. Regardless of development, winds and waves will likely increase between 77W and the Yucatan Peninsula Fri and Sat. ...ATLANTIC OCEAN... A 1010 mb low pressure is located near 23N49W is moving NW at 10 to 15 kt. Fresh to strong winds are noted NE of the low center. The system is producing a small area of showers and thunderstorms near the center. Little development of this system is expected during the next day or two due while it moves northwestward at about 10 to 15 kt over marginally conducive ocean temperatures and is affected by strong upper- level winds. Afterwards, environmental conditions are expected to become more conducive for development, and a tropical depression is likely to form by the end of the week while the system turns eastward over the central Atlantic. For more details, please see the latest Tropical Weather Outlook. Northwest of the low, a weak surface trough extends from a weakening stationary front north of the area to 24N55W. Scattered moderate showers are noted SE of the trough from 27N to 29N. A surface trough extends from 28N68W to 21N69W. Fresh to locally strong winds are SE of the trough. Scattered moderate isolated strong convection is noted from 23N to 30N between 64W and 74W. Fresh to strong winds are also noted west of the tropical wave near 28W from 16N to 20N. Elsewhere, gentle to moderate winds prevail over the discussion waters. Seas are in the 8-10 ft range in the areas where strong winds are noted. Elsewhere over the open waters, seas are in the 4-6 ft range. For the forecast W of 65W: a surface trough just east of the Bahamas will move westward, bringing strong NE to E winds over the central Bahamas tonight. By Thu morning, the surface trough will extend from 30N78W to the western tip of Cuba, bringing fresh to locally strong E winds to the east of northern Florida before the trough weakens by late Thu. Otherwise, a 1022 mb high pressure located near Bermuda will dominate the remainder of the forecast region through at least Wed. Fresh to locally strong winds are expected to pulse N of Hispaniola during the evening hours through Sat night. $$ AL