000 AXNT20 KNHC 012124 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 0005 UTC Sat Oct 2 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 2100 UTC. ...SPECIAL FEATURES... Hurricane Sam is centered near 30.0N 61.8W at 2100 UTC or 210 nm SE of Bermuda moving N at 17 kt. Estimated minimum central pressure is 937 mb. Maximum sustained wind speed is 130 kt with gusts to 160 kt. Numerous moderate to strong convection extends outward from the center 180 NM in the N semicircle and 90 NM in the S semicircle. Scattered moderate convection exists elsewhere within 300 nm N quadrant. Maximum significant wave height near the center is estimated at 43 ft with 12 ft seas extending outward as much as 270 NM from the center. Sam is expected to turn NE at a slightly slower forward speed this weekend. Slow weakening is anticipated over the next several days as it moves over progressively cooler waters and into an environment with more unfavorable wind shear. However, Sam is expected to remain a major hurricane through Saturday night. Early next week, Sam may begin to transition to a strong extratropical storm. Please read the latest High Seas Forecast issued by the National Hurricane Center at website https://www.nhc.noaa.gov/text/MIAHSFAT2.shtml and the latest NHC Forecast/Advisory and Public Advisory at www.hurricanes.gov for more details. Tropical Storm Victor is centered near 12.0N 34.3W at 01/2100 UTC or 650 nm WSW of the Cabo Verde Islands moving WNW at 11 kt. Estimated minimum central pressure is 997 mb. Maximum sustained wind speed is 55 kt with gusts to 65 kt. Numerous moderate to strong convection is noted within 120 NM of the center. Scattered moderate convection is located elsewhere within 240 NM NE quadrant. Maximum significant wave height near the center is estimated to be near 19 ft and the seas should gradually diminish during the next couple days. Victor is forecast to turn NW Sat, then continue moving NW through early next week. The tropical storm is expected to weaken over the next several days due to very unfavorable environmental conditions. Please read the latest High Seas Forecasts issued by Meteo-France at website http://weather.gmdss.org/II.html and by the National Hurricane Center at website https://www.nhc.noaa.gov/text/MIAHSFAT2.shtml as well as the latest NHC Forecast/Advisory and Public Advisory at www.hurricanes.gov for more details. ...TROPICAL WAVES... A tropical wave axis extends along 56W from 05N to 17N, moving W at 10 to 15 kt. Scattered moderate convection is noted from 08N to 10N between 48W and 57W. ...MONSOON TROUGH/ITCZ... A monsoon trough extends from the coast of Liberia near 04N09W to 05N19W. The ITCZ then extends from 05N19W to 05N25W. The ITCZ resumes to the west of Tropical Storm Victor near 07N37W and continues to 06N47W. Aside from convection associated with Victor and the tropical wave, described in the sections above, scattered moderate to isolated strong convection extends from 01N to 08N between 10W and 23W. Scattered moderate convection is noted from 06N to 09N between 42W and 50W. GULF OF MEXICO... Surface ridging N of the Gulf of Mexico is prompting mainly moderate or weaker SE winds across most of the basin, but some fresh NE winds are occurring in association with a weak diurnal trough over the Yucatan Peninsula. Also, with high pressure building S into the SW Atlantic, the pressure gradient has increased over the SE Gulf and fresh E winds are also occurring in the Florida Straits, N of Cuba, and adjacent sections of the Gulf. Seas are 2 to 4 ft. Scattered moderate to isolated strong convection within 90 nm of the Texas coast is associated with a warm front retreating away from the Gulf, through Texas. For the forecast, the weak ridge of high pressure will persist north of the Gulf through tonight, supporting tranquil conditions. Stronger higher pressure will build across the region by Sun, allowing winds and seas to increase over the SE Gulf over the weekend. A weak cold front should move across the Gulf on Mon and Tue, with little enhancement of the winds and seas. CARIBBEAN SEA... A fairly modest pressure gradient is supporting mainly moderate trades over the basin today, with seas of 2 to 4 ft. The eastern N Pacific monsoon trough extends along 10N into the SW Caribbean, and is inducing scattered moderate convection along and S of 11N. Also, an upper level disturbance is assisting in the development of scattered moderate to isolated strong convection over the eastern basin, from 13N to 17N between 62W and 70W. Diurnal heading has spawned convection over mainly the land masses of the Greater Antilles and Venezuela, but some of this activity is impact waters within 60 miles of the coasts. For the forecast, high pressure will build north of the area this weekend. This will bring an increase in trade-winds and seas across the central and E Caribbean as well as the tropical N Atlantic this weekend through the middle of next week. ATLANTIC OCEAN... Refer to the Special Features section above for details on Major Hurricane Sam and Tropical Storm Victor. The Cumbre Vieja volcano on the island of La Palma in the Canary Islands near 28.6N 17.8W has been erupting since September 19th. High concentration of volcanic ash is found near the volcano. Marine and aviation interests should monitor this ongoing situation by reading the latest Volcanic Ash Advisory issued by Meteo-France at http://vaac.meteo.fr/volcanoes/la-palma/ for details. Aside from Hurricane Sam and Tropical Storm Victor, the tropical N Atlantic is dominated by ridging from a double-barreled high pressure of 1031 mb over the Azores and 1030 mb centered near 37N38W. Moderate to fresh NE to E trades encompass the basin south of this ridging. Seas outside of tropical cyclones are generally 6 to 9 ft. A previous cold front in the SW Atlantic has devolved into a low pressure trough, that stretches this evening from 30N66W to 27N75W. Winds and seas on both sides of this trough are moderate and 5 to 7 ft, respectively. For the forecast west of 55W, Swells generated from Major Hurricane Sam, centered E of the area, will impact waters northeast of the Bahamas through the weekend. High pressure will build in to the area in the wake of Sam, which will bring continued moderate to occasionally fresh winds through Tue. $$ KONARIK