000 AXNT20 KNHC 201753 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1805 UTC Mon Sep 20 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 1200 UTC surface analysis and satellite imagery through 1720 UTC. ...SPECIAL FEATURES... The center of Tropical Storm PETER, at 20/1500 UTC, is near 19.5N 60.9W. Peter is moving toward the west-northwest, or 290 degrees, 13 knots. The estimated minimum central pressure is 1007 mb. The maximum sustained wind speeds are 45 knots with gusts to 55 knots. Precipitation: scattered to numerous strong in clusters is within 210 nm of the center in the NE semicircle. Widely scattered moderate to isolated strong is elsewhere, from T.S. Peter and the Greater Antilles to the 31N58W-to-29N69W cold front, between 54W and 70W. Please, read the latest NHC Public Advisory at: https://www.nhc.noaa.gov/text/MIATCPAT1.shtml, and the Forecast/Advisory at: https://www.nhc.noaa.gov/text/MIATCMAT1.shtml, for more details. The center of Tropical Storm ROSE, at 20/1500 UTC, is near 17.3N 33.4W. Rose is moving toward the northwest, or 320 degrees, 14 knots. The estimated minimum central pressure is 1007 mb. The maximum sustained wind speeds are 35 knots with gusts to 45 knots. Precipitation: numerous strong is within 135 nm of the center in the western quadrant. Isolated moderate is elsewhere within 660 nm of the center in the northern semicircle. Please, read the latest NHC Public Advisory at: https://www.nhc.noaa.gov/text/MIATCPAT2.shtml, and the Forecast/Advisory at: https://www.nhc.noaa.gov/text/MIATCMAT2.shtml, for more details. ...TROPICAL WAVES... An Atlantic Ocean tropical wave is along 20W/21W, from 19N southward, moving westward 10 to 15 knots. A 1009 mb low pressure center is along the tropical wave, near 09.5N. The precipitation pattern is showing some signs of organization. Upper level winds are expected to become more conducive for further development by the middle of the week. A tropical depression is likely to form by Friday, while the system moves westward 10 to 15 mph, through the eastern and central sections of the tropical Atlantic Ocean. Precipitation: widely scattered moderate to isolated strong is within 360 nm of the center in the NW quadrant. Please, refer to the Tropical Weather Outlook, at www.nhc.noaa.gov/gtwo.php?basin=atlc&fdays=2, for more details. ...MONSOON TROUGH/ITCZ... The monsoon trough passes through the coastal plains of Guinea-Bissau near 12N16W, to the 1009 mb low pressure center that is along the 20W/21W tropical wave, to 07N30W and 07N38W. The ITCZ continues from 07N38W to 08N42W, and to the coastal plains of NE French Guiana. Precipitation: widely scattered moderate to isolated strong is from 02N to 07N between 50W and 56W, mostly inland in parts of Brazil, French Guiana, and Suriname, and elsewhere in the coastal waters of those countries. GULF OF MEXICO... A surface trough extends from the Florida Panhandle to the eastern sections of Texas. Precipitation: widely scattered moderate to isolated strong is within 180 nm of the coast of the U.S.A. from 90W eastward. Isolated moderate is within 180 nm of the coast of the U.S.A. and Mexico, from 23N northward from 90W westward. 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. CARIBBEAN SEA... An upper level trough passes through the SE Bahamas near 22N73W, across SE Cuba, to the central coast of eastern Nicaragua. Precipitation: isolated moderate to locally strong is to the north of the line that runs from 15N70W to the central coast of eastern Nicaragua. The eastern extension of the eastern Pacific Ocean monsoon trough is along 09N/10N, between 74W in Colombia, beyond southern Costa Rica, and into the eastern Pacific Ocean. Precipitation: scattered to numerous strong in individual clusters is within 60 nm on either side of the monsoon trough in the SW corner of the Caribbean Sea. Tropical Storm Peter is northeast of the Leeward Islands near 19.5N 60.9W 1007 mb at 1500 UTC moving WNW at 13 kt. Maximum sustained winds are 45 kt with gusts to 55 kt. Peter will continue to move WNW and reach near 20.8N 64.8W Tue morning, then begin to turn more NW and slowly weaken, reaching near 22.7N 67.9W Wed morning, then weaken to a tropical depression as it continues to move northward toward Bermuda through the rest of the week. As this occurs, trade winds over the south-central Caribbean will diminish through Thu night. Look for associated showers and thunderstorms to affect the NE Caribbean and adjacent waters through tonight. ATLANTIC OCEAN... Information about Tropical Storm Peter, and about Tropical Storm Rose, is given in the SPECIAL FEATURES section, . A cold front passes through 31N58W to 29N69W. A stationary front continues from 29N69W, northwestward, beyond NE Florida/SE Georgia. An upper level cyclonic circulation center is about 420 nm to the northwest of T.S. Peter. Precipitation: scattered to numerous strong is from 29N to 32N between 77W and 80W. Widely scattered moderate to isolated strong is elsewhere within 120 nm on either side of the frontal boundary, and from Cuba to 28N between 75W and Florida. Widely scattered moderate to isolated strong also covers the waters that are from T.S. Peter and the Greater Antilles to the 31N58W-to-29N69W cold front, between 54W and 70W. The Cumbre Vieja volcano, that is on the island of La Palma in the Canary Islands, has been erupting since 19/1410 UTC. Marine and aviation interests should monitor this on-going situation by reading the Volcanic Ash Advisory, that is issued by Meteo- France, at http://vaac.meteo.fr/volcanoes/la-palma/. Tropical Storm Peter is northeast of the Leeward Islands near 19.5N 60.9W 1007 mb at 1500 UTC moving WNW at 13 kt. Maximum sustained winds are 45 kt with gusts to 55 kt. Peter will continue to move WNW and reach near 20.8N 64.8W Tue morning, then begin to turn more NW and slowly weaken, reaching near 22.7N 67.9W Wed morning. Peter will weaken to a tropical depression near 23.5N 68.6W Wed evening, then move to 24.5N 68.7W by Thu morning. Peter will change little in intensity as it moves northward toward Bermuda throughout the rest of the week. Elsewhere west of 70W, gentle to moderate winds and slight to moderate seas will persist over open waters through the early part of the week, with swell to 8 ft associated with the tropical storm reaching the waters east of 72W by Wed. $$ MT