762 AXNT20 KNHC 111037 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1205 UTC Sun Aug 11 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 0600 UTC surface analysis and satellite imagery through 0920 UTC. ...SPECIAL FEATURES... A complex tropical wave is along 43W from 20N southward, moving W near 15 kt. The monsoon trough extends through this region to beyond 50W. Earlier ASCAT scatterometer wind data and satellite imagery suggest that there may be 2 weak surface low centers along the monsoon trough in the vicinity of the wave. A 1009 mb low center is analyzed at 0600 UTC near 12.5N43.5W. Scattered moderate isolated strong convection is noted about this broad circulation from 07.5N to 15N between 41W and 55W. Environmental conditions appear conducive for gradual development of this system during the next few days while it moves westward to west- northwestward at 15 to 20 kt across the central tropical Atlantic. A tropical depression is likely to form by the early to middle part of next week while the system approaches and then moves near or over the Lesser Antilles, and interests there should monitor the progress of this system. Then, the system is forecast to move generally west-northwestward and could approach portions of the Greater Antilles by the middle to latter part of next week. This system has a medium chance of development through 48 hours and high chance of development in 7 days. ...TROPICAL WAVES... A new tropical wave is analyzed with its axis along 22W from 21N southward. Scattered moderate isolated strong convection is noted from 09N to 12N between the west coast of Africa and the 22W, and also from 10.5N to 11.5N between 24W and 28W. A Caribbean tropical wave has its axis along 76W from 20N southward into Colombia, and is moving W at around 15 kt. Scattered moderate isolated strong convection is noted S of 11N between 74W and 79W, and ahead of the wave, from 12N to 16N between 79W and 84W. ...MONSOON TROUGH/ITCZ... The monsoon trough extends off the coast of Mauritania near 20.5N16.5W to 12.5N30W to a 1009 mb low pressure near 12.5N43.5W to 10N52W. See the Special Features and Tropical Waves sections for information on convection. The eastern end of the East Pacific monsoon trough is triggering scattered showers and thunderstorms across the Caribbean waters S of 11N across the waters and coasts of Panama and northwestern Colombia. ...GULF OF MEXICO... A surface trough over the northern Gulf has dissipated. A surface trough across the central Bay of Campeche continues to drift westward, and is triggering scattered to numerous moderate to strong convection across the SW Gulf south of 23.5N. A weak surface ridge extends through the Straits of Florida westward along 25N and into the Mexican coast. Outside of convection, gentle to locally moderate winds and 1 to 3 ft seas are present for the entire basin. For the forecast, the north portion of a tropical wave moving westward across southern Mexico and the Bay of Campeche will continue to support scattered showers and thunderstorms across the Bay of Campeche and SW Gulf through Sun evening. Otherwise, a weak surface ridge will maintain gentle to moderate winds and slight seas across most of the basin through Thu. ...CARIBBEAN SEA... A surface ridge over and east of the Bahamas is maintaining moderate to locally fresh trade winds for much of the basin. A surface trough along 67W is triggering scattered moderate convection in the southeastern Basin. A line of scattered moderate isolated strong convection is noted across the NW basin from central Cuba waters to near the Gulf of Honduras. Refer to the Monsoon trough/ITCZ and Tropical Waves sections for additional weather in the Caribbean Sea. Fresh to strong NE winds are present over the Windward Passage with seas 6 to 7 ft. Moderate to fresh ENE to E trades with 4 to 6 ft seas are present at the central basin. Gentle to moderate ENE to ESE winds and seas of 3 to 5 ft prevail for the rest of the basin. For the forecast, moderate to locally fresh trades will prevail across the basin through Mon. A robust tropical wave currently in the central Atlantic is expected to gradually develop over the next few days, and a tropical depression is likely to form by the early part of this week while the system approaches and then moves near or over the Lesser Antilles. Then, this system is forecast to move generally west-northwestward and could approach portions of the Greater Antilles by the middle to latter part of this week. Regardless of development, gale conditions are expected to begin affecting the extreme NE Caribbean and adjacent Atlantic waters beginning early Tue morning. ...ATLANTIC OCEAN... A line of scattered moderate convection extends from NE of the Bahamas near 25N74W to beyond 31N70W. Similar convection is noted extending from just north of Puerto Rico to the SE Bahamas, associated with a low level trough. For additional convection in the Atlantic Basin, read the Monsoon Trough/ITCZ and Tropical Waves sections at the above. The Bermuda-Azores high dominates most of the Atlantic waters, supporting gentle to moderate NE to E winds and seas of 4 to 7 ft north of 23N between 30W and 75W, while winds are S to SW at less than 15 kt to between 75W and Florida and Georgia coasts. South of 23N between 30W and the Lesser Antilles, moderate to locally fresh NE winds along with 5 to 8 ft seas prevail. Fresh to strong winds associated with the tropical wave moving away from Africa are found from 12N to the Canary Islands between the west coast of Africa and 30W. Seas in this area are 6 to 10 ft. For the forecast west of 55W, Atlantic high pressure centered NE of Bermuda extends a ridge southwestward across the Northern Bahamas and central Florida, and will remain in place through Mon, then shift NE and weaken through Wed. This pattern will promote gentle to moderate winds and slight to moderate seas, except for fresh to strong winds during the evening and nighttime hours along the north coast of Hispaniola through Mon. A robust tropical wave currently in the central Atlantic is expected to gradually develop over the next few days, and a tropical depression is likely to form by the early part of this week while the system approaches and then moves near or over the Lesser Antilles. Then, this system is forecast to move generally west-northwestward and could approach portions of the Greater Antilles by the middle to latter part of this week. Regardless of development, gale conditions are expected to begin affecting the SE Atlantic waters and portions of the extreme NE Caribbean beginning early Wed morning. $$ Stripling