000 AXNT20 KNHC 162326 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 0005 UTC Mon Aug 16 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 2300 UTC. ...SPECIAL FEATURES... Tropical Storm Fred is centered inland near 29.9N 85.3W at 16/2100 UTC or 20 nm NW of Apalachicola Florida, moving NNE at 8 kt. Estimated minimum central pressure is 995 mb. Maximum sustained wind speed is 50 kt with gusts to 60 kt. Numerous moderate to isolated strong convection is noted north of 29N between 84W to 87W. Scattered moderate convection prevails north of 25N and east of 85W. Seas of 12 ft or greater are expected within 75 nm SE quadrant and 60 NM SW quadrant, with maximum seas of 18 ft. Rapid weakening is expected, and Fred should become a tropical depression by early Tuesday. On the forecast track, Fred will move from western Georgia on Tuesday across the southern Appalachian Mountains to West Virginia by Wednesday. 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. Tropical Depression Grace is centered near 17.9N 72.4W at 16/2100 UTC or 40 nm S of Port Au Prince Haiti moving WNW at 11 kt. Estimated minimum central pressure is 1007 mb. Maximum sustained wind speed is 30 kt with gusts to 40 kt. Numerous moderate isolated strong convection is noted from 15N to 21N between 70W and 75W, while scattered moderate convection is noted from 16N to 24N between 65W and 70W. Seas of 4-6 ft prevail within the strongest convection. Strengthening is forecast during the next few days, and Grace is expected to regain tropical storm status on Tuesday. Grace could be near hurricane strength when it approaches the Yucatan Peninsula of Mexico Wednesday night. Please read the latest NHC Public Advisory at https://www.nhc.noaa.gov/text/MIATCPAT2.shtml and Forecast/ Advisory at https://www.nhc.noaa.gov/text/MIATCMAT2.shtml for more details. Tropical Depression Eight has intensified to Tropical Storm Henri, centered near 31.0N 62.9W at 16/2100 UTC, or 130 nm SE of Bermuda, moving SSW at 6 kt. Estimated minimum central pressure is 1010 mb. Maximum sustained wind speed is 35 kt with gusts to 45 kt. Scattered moderate to isolated strong convection is noted in the southern semicircle from 28N to 31N between 61W and 64W. Seas near the convection range between 7 and 9 ft. A slow clockwise turn toward the southwest and then toward the west is expected during the next day or two. On the forecast track, the center of Henri should pass well to the south of Bermuda late Tuesday or Tuesday night. Please read the latest NHC Public Advisory at https://www.nhc.noaa.gov/text/MIATCPAT3.shtml and Forecast/Advisory at https://www.nhc.noaa.gov/text/MIATCMAT3.shtml for more details. ...TROPICAL WAVES... A far eastern Atlantic tropical wave extends its axis along 35W from 21N southward, moving westward at 10-15 kt. Scattered moderate convection is from 05N-09N between 26W-38W. A central Atlantic tropical wave extends its axis along 51W from 20N southward, moving westward at 10-15 kt. Scattered showers are in the vicinity of the wave axis. A western Caribbean tropical wave extends its axis along 84W from south of 21N to northern Costa Rica. THe wave is moving westward at 10 to 15 kt. Scattered moderate convection is noted over land mainly south of 15N between 83W-88W. ...MONSOON TROUGH/ITCZ... The monsoon trough extends from the border of Guinea-Bissau near 12N16W to 11N30W to 08N44W. The ITCZ is analyzed 08N52W to 07N57W. Scattered moderate to isolated strong convection is near the monsoon trough from 04N to 11N E of 27W to the coast of Africa, and near the ITCZ from 07N to 09N between 52W to 60W. ...GULF OF MEXICO... Refer to the Special Features section above for details on Tropical Storm Fred. Moderate south to southeast winds were detected over the SE Gulf by the latest ASCAT pass, while light to gentle easterly winds prevail across the western Gulf. Seas are 2-3 ft in the western Gulf and increasing to 4 to 8 ft towards the E and NE associated to from Tropical Storm Fred. The diurnal trough is analyzed over the Bay of Campeche from 24N90W to 20N94W. Scattered showers are noted near the trough axis. For the forecast, T.S. Fred will move inland to 31.5N 85.1W Tue morning, and continue well inland on Tue afternoon with winds and waves diminishing over the Gulf. Tropical Depression Grace is expected to strengthen to a tropical storm and reach the Yucatan Channel Thu morning, move to near the N coast of Yucatan Thu afternoon, and become a hurricane over the W Gulf by Fri. ...CARIBBEAN SEA... Refer to the sections above for details on Tropical Depression Grace and the tropical wave moving across the basin. Outside of the wind field of Grace, latest ASCAT data depicts moderate to fresh winds in the eastern Caribbean and light to gentle trades west of 70W, pulsing to moderate in the Gulf of Honduras. Seas are 2-3 ft over the central and eastern Caribbean. For the forecast, Grace will move over Haiti Tue morning, strengthen to a tropical storm between Jamaica and Cuba Tue afternoon, south of central Cuba Wed morning, south of W Cuba Wed afternoon, over the Yucatan Channel Thu morning, and near the N coast of Yucatan Thu afternoon. Elsewhere the NE to E trades will be fresh to strong over the S central Caribbean Tue and Wed. ...ATLANTIC OCEAN... Please refer to the sections above for details on upgraded Tropical Storm Henri and the tropical waves moving across the basin. Surface ridging and a weak pressure gradient prevails across the tropical Atlantic. Mainly moderate trades are pulsing to fresh winds from 24N to the coast of Hispaniola. Gentle to moderate east to southeast winds are over the western Atlantic, including the Bahamas and Turks and Caicos. Light winds are north of 24N between 31W and 64W. Scattered showers and thunderstorms are noted from 26N and west of 74W. Gentle to moderate trades are south of 24N in the remainder of the basin, except moderate N to NW winds noted North of 18N to the Canary Islands. Seas are 4-6 ft to the far east and near Puerto Rico and the Dominican Republic south of 24N and east of 68W. Seas are 3-4 ft near the Lesser Antilles. For the forecast west of 65W, Tropical Depression Grace will move over Haiti Tue morning, strengthen to a tropical storm between Jamaica and Cuba Tue afternoon, and continue westward in the Caribbean and the Gulf of Mexico afterwards. Tropical Storm Henri will move to 30.5N 63.4W Tue morning, 30.3N 64.2W Tue afternoon, 30.2N 65.4W Wed morning, 30.2N 66.9W Wed afternoon, 30.3N 68.5W Thu morning, and 30.5N 69.9W Thu afternoon. Henri will change little in intensity as it moves to 31.8N 70.2W Fri afternoon. Elsewhere, high pressure will persist across the area through the period. $$ ERA