000 AXNT20 KNHC 110941 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1205 UTC Wed Aug 11 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 0600 UTC surface analysis and satellite imagery through 1000 UTC. ...SPECIAL FEATURES... Tropical Storm Fred is centered near 18.0N 68.2W at 11/0900 UTC or 100 nm ESE of Santo Domingo Dominican Republic moving WNW at 14 kt. Estimated minimum central pressure is 1009 mb. Maximum sustained wind speed is 35 kt with gusts to 45 kt. Numerous moderate and scattered strong convection is noted within 60 nm NW and 120 nm SW semicircles of Fred. Fred will move into E Hispaniola this morning, with the mountainous terrain expected to weaken the system to a tropical depression this afternoon. Fred is forecast to emerge off the NW coast of Hispaniola as a tropical depression later tonight. The system is forecast to re- intensify to tropical storm strength Thursday and continue on a WNW track just north of Cuba Thu and Fri, approaching the Florida Straits Fri night. Heavy rainfall could lead to flash, urban, and small stream flooding, along with possible rapid river rises and the potential for mudslides across portions of Hispaniola today. Please read the latest NHC Public Advisory at https://www.nhc.noaa.gov/text/MIATCPAT1.shtml and Forecast/ Advisory at https://www.nhc.noaa.gov/text/MIATCMAT1.shtml for more details on Fred. ...TROPICAL WAVES... The axis of a tropical wave is near 31N from 18N southward, moving westward at 10 to 15 kt. Scattered moderate convection is noted within 60 nm of the wave axis from 08N to 11N. The axis of a tropical wave is near 46/47W from 20N southward, moving westward at 10-15 kt. Scattered moderate to isolated strong convection is noted within 60 nm of the wave axis from 05N to 10N. The axis of a tropical wave is near 68W south of TS Fred, moving westward at 10 to 15 kt. Scattered showers are in the vicinity of the wave axis. The axis of a tropical wave is near 85W, from 20N southward, moving W at 10-15 kt. Scattered moderate isolated strong convection is over the NW Caribbean. ...MONSOON TROUGH/ITCZ... The monsoon trough extends from 12N16W to 11N23W to 12.5N31W to 11.5N41W. The ITCZ extends from 12N49W to 07N59W. Aside from convection described above in the Special Features and Tropical Waves sections, scattered moderate isolated strong convection is from 05N to 13N between 32W and 43W and from 05N to 10N between 48W and 52W. ...GULF OF MEXICO... High pressure prevails over the northern Gulf. A surface trough extends just west of the Yucatan peninsula. Moderate to fresh winds are noted over the SW Gulf in the vicinity of the trough, as well as the far SE Gulf. Light to gentle winds are noted over the NE Gulf. Gentle to moderate winds prevail elsewhere. Seas are in the 3-5 ft range west of the Yucatan peninsula and over the fat SE Gulf. Seas are in the 1-3 ft range elsewhere. For the forecast, moderate to fresh E winds will pulse off the NW Yucatan Peninsula into the Bay of Campeche tonight in association with a diurnal trough. Elsewhere, a weak surface ridge will prevail along 30N through Thu. Tropical Storm Fred near 18.0N 68.2W 1009 mb at 5 AM EDT moving WNW at 14 kt. Maximum sustained winds 35 kt gusts 45 kt. Fred is expected to move across the Straits of Florida Fri night as a tropical storm, into the SE Gulf of Mexico Sat, and move NW along the far E Gulf through the weekend. ...CARIBBEAN SEA... Please see the Special Features section for further details on Tropical Storm Fred. Outside of Tropical Storm Fred, fresh to strong winds prevail over the south central Caribbean, with gentle to moderate winds elsewhere. Seas are in the 6-8 ft range over the south central Caribbean and 3-5 ft elsewhere. For the forecast, fresh to strong winds over the south central Caribbean will diminish today. Tropical Storm Fred near 18.0N 68.2W 1009 mb at 5 AM EDT moving WNW at 14 kt. Maximum sustained winds 35 kt gusts 45 kt. Fred will reach E Hispaniola this morning, move north of Hispaniola Wed night, and then move north of Cuba Thu and Fri. ...ATLANTIC OCEAN... Please see Special Features section above for more on Tropical Storm Fred. Outside of Fred, high pressure prevail over the subtropical waters N of 20N. Light to gentle winds are N of 27N, with gentle to moderate winds elsewhere N of 20N. Seas are in the 3-5 ft range N of 28N, and 5-7 ft elsewhere N of 20N. Over the deep tropics S of 20N, gentle to moderate winds prevail N of 10N, and light to gentle winds prevail S of 10N. Seas are in the 5-7 ft range N of 10N and 4-5 ft S of 10N. For the forecast W of 65W, Atlc surface ridge associated with the Bermuda- Azores high will persist with axis N of the area for the next several days. Tropical Storm Fred near 18.0N 68.2W 1009 mb at 5 AM EDT moving WNW at 14 kt. Maximum sustained winds 35 kt gusts 45 kt. Fred will reach E Hispaniola this morning, move north of Hispaniola Wed night as a tropical depression, and then re- intensify to a tropical storm as the system continue west northwestward to the north of Cuba Thu and Fri. $$ AL