000 AXNT20 KNHC 211044 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1205 UTC Tue Sep 21 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 1030 UTC. ...SPECIAL FEATURES... Tropical Storm Peter is centered near 19.6N 63.8W at 21/0900 UTC or 90 nm NNW of the Northern Leeward Islands moving W at 10 kt. Estimated minimum central pressure is 1007 mb. Maximum sustained wind speed is 45 kt with gusts to 55 kt. Seas are peaking at 12 to 14 ft near and just N of the center. Scattered moderate to isolated strong convection is observed within 150 nm to the northeast of the center. Peter will continue to move WNW to the north of the Virgin Islands and Puerto Rico today and Tue, before weakening to a tropical depression and turning more N to NNE by mid week. Peter will then continue to move toward the south of Bermuda through Sat. Currently a few showers are noted over the northern Leeward Islands, but heavy rainfall remains possible over the next couple of days, as far west as Hispaniola. Swells generated by Peter are affecting the northern Leeward Islands and Puerto Rico, and will continue spreading westward to Hispaniola later today and the Bahamas on Wednesday. These swells could cause life- threatening surf and rip current conditions. Please consult products from your local weather office. 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. Marine interests in the area can read the latest NHC Offshore Waters Forecasts at https://www.nhc.noaa.gov/marine/offshores.php Tropical Storm Rose is centered near 21.0N 36.4W at 21/0900 UTC or 760 nm WNW of the Cabo Verde Islands moving NW at 17 kt. Estimated minimum central pressure is 1006 mb. Maximum sustained wind speed is 40 kt with gusts to 50 kt. Seas are peaking at 12 near and just NE of the center. Scattered moderate convection is found within 90 nm to the northeast of the center. Rose is expected to continue on a NW track with a decrease in forward speed through Wed, then turn toward NNW on Thu. No significant change in strength is anticipated through Tuesday, with weakening likely beginning Tue 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. For sea conditions near this system, please read the Meteo-France High Seas Forecast at http://weather.gmdss.org/II.html Showers and thunderstorms associated with a tropical wave located a few hundred miles south-southwest of the Cabo Verde Islands continue to show some signs of organization. Environmental conditions are expected to become more conducive for development, and a tropical depression is likely to form later this week while the system moves westward at 10 to 15 mph across the eastern and central tropical Atlantic Ocean. This system has a medium chance of formation in the next 48 hours. For more information, refer to the latest NHC Tropical Weather Outlook at https://nhc.noaa.gov/gtwo.php?basin=atlc&fdays=2 ...TROPICAL WAVES... An Atlantic tropical wave is near 25W/26W from the southernmost Cabo Verde Islands southward through a 1010 mb low near 10N26W, and moving W near 15 knots. Scattered moderate convection is present within 150 nm of the low. Refer to the Special Features section above for formation potential of this system. ...MONSOON TROUGH/ITCZ... A monsoon trough enters the Atlantic ocean at the Senegal/Guinea- Bissau coast near 12N17W through the above mentioned 1010 mb low pressure to 09N35W. The ITCZ then continues from 09N35W to 05N48W. Other than the convection near the tropical wave/low, no significant convection is evident near the monsoon trough or ITCZ. ...GULF OF MEXICO... A modest 1015 mb high over the E Gulf near 26N86W is dominating the entire area with light to gentle winds and seas of 2 to 3 ft. For the forecast,the weak high pressure will extend across the eastern and central Gulf of Mexico through Tue. This pattern will support continued gentle to moderate winds and mostly slight seas across the Gulf. An early season cold front is expected to enter the NW Gulf early Wed and reach from the NE Gulf to central Bay of Campeche by late Thu before stalling, supporting increased winds and seas over the northwest and north-central Gulf Tue night through Thu. ...CARIBBEAN SEA... Please read the Special Features section above for details on Tropical Storm Peter which is forecast to track well north of the NE Caribbean. Aided by an upper-level low extending from eastern Cuba to San Andres Island, convergent trades are triggering scattered showers and isolated thunderstorms south of Hispaniola and along the coast of Panama. Moderate trades and seas near 4 ft exit across the S central basin, while gentle trades and seas at 2 to 3 ft prevail for the remainder of the basin. For the forecast, Peter will move north of Puerto Rico and the Virgin Islands to 20.3N 65.3W this afternoon, then continue north of the area through mid week, before weakening to a tropical depression and continuing to south of Bermuda by the end of the week. As this occurs, trade winds over the south- central Caribbean will diminish through Thu night. ...ATLANTIC OCEAN... Please read the Special Features section above for details on Tropical Storm Peter located N of the northern Leeward Islands and Tropical Storm Rose situated WNW of the Cabo Verde Islands. In addition, the potential of tropical cyclone formation for a tropical wave/low pressure near the Cabo Verde Islands is also available. The Cumbre Vieja volcano on the island of La Palma in the Canary Islands has been erupting since 19/1410 UTC. The ash plume is expected to remain below 8,000 ft west of the volcano while drifting SW, causing a reduction in visibility. Marine and aviation interests should monitor this on-going situation by reading Volcanic Ash Advisory issued by Meteo-France at http://vaac.meteo.fr/volcanoes/la-palma/ A cold front extends west-southwestward, entering the forecast area near 32N50W to 29N60W then is stationary to the near the Florida-Georgia border. Scattered showers and thunderstorms are occurring near and S of this frontal boundary. Convergent trades are causing similar conditions over the SE Bahamas and Turks/Caicos Islands. A robust upper- level trough well W of the Canary Islands from 32N30W to 20N40W is producing numerous moderate to isolated strong convection from 20N to 28N between 26W and 33W. Refer to the Tropical Waves section for additional convection in the Atlantic Basin. Outside the influence of Tropical Storms Peter and Rose, gentle to moderate with locally fresh winds and seas at 4 to 6 ft are present N of 20N and west of 40W. Mostly moderate to fresh NE trades and seas of 5 to 7 ft are found elsewhere. For the forecast west of 65W, Tropical Storm Peter near 19.6N 63.8W 1007 mb at 0900 UTC moving W at 10 kt. Maximum sustained winds 45 kt gusts 55 kt. Peter will move north of the Virgin Islands and Puerto Rico to 20.3N 65.3W this afternoon, then continue to well north of the Mona Passage to 21.2N 66.9W by Wed morning. Peter will continue to 22.2N 67.9W Wed afternoon, 23.2N 68.2W Thu morning, then turn more northward and weaken to a tropical depression near 24.0N 68.0W Thu afternoon, before moving on to 25.2N 67.2W by Fri morning and continuing to the south of the Bermuda through Sat. Elsewhere west of 70W, gentle to moderate winds and slight to moderate seas will persist over open waters through the week. $$ Christensen