000 AXNT20 KNHC 191110 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1205 UTC Thu Aug 19 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 1150 UTC. ...SPECIAL FEATURES... Hurricane Grace is centered near 20.1N 87.5W at 19/0945 UTC or 10 nm S of Tulum Mexico moving W at 15 kt. Estimated minimum central pressure is 986 mb. Maximum sustained wind speed is 70 kt with gusts to 85 kt. Peak seas are 28 ft. Scattered moderate isolated strong convection is from 17N to 21N between 83W and 87W. Grace made landfall along the eastern Yucatan Peninsula near Tulum, is expected to move across the Yucatan Peninsula today, and move over the southwest Gulf of Mexico late tonight through Friday. Grace is expected to weaken as it crosses Yucatan, but re-intensification is expected when the center reaches the Gulf of Mexico. 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 Storm Henri is centered near 29.5N 69.5W at 19/0900 UTC or 460 nm SE of Cape Hatteras North Carolina moving W at 8 kt. Estimated minimum central pressure is 995 mb. Maximum sustained wind speed is 60 kt with gusts to 75 kt. Peak seas are 23 ft. Numerous moderate convection is from 27N to 31N between 67W and 73W. On the forecast track, the center of Henri will remain well offshore the east coast of the United States over the next couple of days but could approach southeastern New England on Sunday. Some strengthening is forecast during the next few days, and Henri is expected to become a hurricane by Friday. 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 tropical wave extends from 02N to 19N with axis near 26W, moving W at 10-15 kt. Scattered moderate convection is from 07N to 15N between 20W and 31W. A tropical wave extends from 03N to 19N with axis near 37W, moving W at 10-15 kt. Scattered moderate convection is from 04N to 13N between 32W and 47W. A tropical wave extends from 06N to 20N with axis near 56W, moving W at around 15 kt. Scattered showers and tstms associated with it are affecting the Lesser Antilles. A tropical wave extends S of 20N with axis near 69W, moving W at around 15 kt. No significant deep convection is currently associated with this wave. ...MONSOON TROUGH/ITCZ... The monsoon trough axis extends from 16N17W to 12N35W to 10N45W. The ITCZ then extends from 10N45W to 08N59W. Aside from the convection associated with the tropical waves, scattered moderate convection is from 09N to 18N between 14W and 20W. ...GULF OF MEXICO... Refer to the Special Features section above for details on Hurricane Grace. Fresh to storm force winds are affecting the northern Yucatan peninsula adjacent waters and the Yucatan channel as Grace continue to move inland. Gentle to moderate return flow is elsewhere as the basin continue to be under the influence of a surface ridge. Grace will weaken to a tropical storm near 20.3N 89.7W this afternoon, reach near 20.6N 92.6W Fri morning, strengthen to a hurricane near 20.5N 95.0W Fri afternoon, move inland and weaken to a tropical storm near 20.1N 97.3W Sat morning, weaken to a tropical depression near 19.7N 100.1W Sat afternoon, and dissipate Sun morning. Conditions associated with Grace will affect the Bay of Campeche tonight through Sat. ...CARIBBEAN SEA... Refer to the Special Features section above for details on Hurricane Grace. Grace will weaken to a tropical storm near 20.3N 89.7W this afternoon, 20.6N 92.6W Fri morning, strengthen to a hurricane near 20.5N 95.0W Fri afternoon, move inland and weaken to a tropical storm near 20.1N 97.3W Sat morning, weaken to a tropical depression near 19.7N 100.1W Sat afternoon, and dissipate Sun morning. Otherwise, moderate to fresh trade winds will dominate elsewhere, except for locally fresh to strong winds in the Gulf of Honduras and south-central Caribbean through tonight. ...ATLANTIC OCEAN... Please refer to the sections above for details on Tropical Storm Henri and on the tropical waves moving across the basin. The 1026 mb Azores-Bermuda subtropical ridge remains the dominant feature in the tropical Atlantic outside of Tropical Storm Henri. This is allowing for fairly tranquil weather conditions across the basin. However, a few showers are noted east of the Lesser Antilles from 13N to 16N and between 56W and 60W. The strong high pressure system and lower pressures over NW Africa result in a tight pressure gradient over the NE Atlantic. Recent scatterometer satellite data show strong to near gale-force N-NE winds surrounding the Canary Islands and off the coasts of Morocco and Western Sahara. Seas in this area are in the 5-8 ft range. An area of fresh to strong NE winds is noted from 19N to 29N and between 35W and 50W, with seas of 5-8 ft. Winds in the rest of the basin are moderate to fresh with seas in the 2-5 ft range. For the forecast west of 65W, Tropical Storm Henri near 29.8N 68.5W 995 mb at 11 PM EDT moving W at 8 kt. Maximum sustained winds 60 kt gusts 75 kt. Henri will move to 29.8N 69.9W Thu morning, 30.0N 71.8W Thu evening, strengthen to a hurricane near 30.7N 72.7W Fri morning, 32.3N 72.8W Fri evening, 34.4N 71.8W Sat morning, and 36.9N 70.7W Sat evening. Henri will change little in intensity as it moves near 40.4N 69.4W late Sun. Elsewhere, high pressure will persist across the forecast waters through the period. Fresh east to southeast winds over the far southwest part of the area will shift W to the Straits of Florida tonight. $$ Ramos