000 AXNT20 KNHC 061046 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1205 UTC Wed Oct 6 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 0930 UTC. ...TROPICAL WAVES... An Atlantic Ocean tropical wave is along 22W, from 18N southward, moving west at 10 to 15 knots. Scattered light convection prevails across the waters between the Cabo Verde Islands and the W coast of Africa. Scattered moderate isolated strong convection is within 60 nm either side of monsoon trough and ITCZ E of 28W. An Atlantic Ocean tropical wave is along 48W, from 19N southward, moving west from 15 to 20 knots. Scattered moderate widely scattered strong convection is from 05N to 14N between 40W and 52W. Satellite imagery suggest SAL accompanies this wave, north of 14N to 25N between 55W and 30W. A Caribbean Sea tropical wave is along 80W, from 18N southward, moving west near 15 knots. Scattered moderate to strong convection covers the area from 14N to 20N between 77W and 84W. ...MONSOON TROUGH/ITCZ... The monsoon trough passes through the coastal plains of Guinea-Bissau near 11.5N16W to 05N18W. The ITCZ continues from 05N18W to 03N22W to 02N28W to 06N47W to coastal Suriname near 5.5N56W. scattered moderate to strong convection is elsewhere from 03N to 11N between 28W and 40W. Widely scattered moderate convection is south of 12N between 52W and 58W. GULF OF MEXICO... A stationary front extends from coastal Mississippi to the Bay of Campeche along 94.5W. Widely scattered moderate convection is seen within 180 nm SE of the front, and covers coastal zones across the Florida Big Bend and the Bay of Campeche. A weak high pressure ridge behind the front and across NE Mexico is promoting gentle to moderate northerly winds behind the front, except for fresh winds across the Veracruz area, where peak seas are 5 ft. Elsewhere E of 88W gentle to moderate SE to S winds prevail, with seas 2 to 4 ft. The stationary front will meander through Thu before dissipating. Weak high pressure to the NW will promote gentle to moderate northerly winds W of trough through Thu, except fresh along the coast near Veracruz. High pressure will build modestly across the basin during the weekend. CARIBBEAN SEA... An upper level trough extends from the western Atlantic across the SE Bahamas to Belize, and is supporting the active convection described with the tropical wave along 80W. South of 12N, scattered strong convection is seen across NW Colombia westward to eastern Costa Rica and southward into the adjacent Pacific. Fresh to strong trade winds are directly behind the tropical wave and extend to 67W. These winds have generated seas of 7 to 9 ft across much of the central Caribbean. Fresh tradewinds prevail E of 67W and into the tropical Atlantic. Seas across the eastern Caribbean are 6 to 7 ft and 8 to 10 ft across the tropical Atlantic in N and NE swell. The eastern extension of the eastern Pacific Ocean monsoon trough extends from 10N74W in Colombia beyond Costa Rica along 09.5N. High pressure currently just NE of Bermuda, will slide ENE throughout the week supporting fresh to strong winds across the central Caribbean through Thu. Winds and seas will then diminish significantly early Fri through Sun as a surface trough moves W across the regional Atlantic waters. Moderate N to NE swell from Sam will affect the tropical Atlc waters and Caribbean passages through Wed night. ATLANTIC OCEAN... A broad middle to upper level level trough extends from near Bermuda SW through the SE Bahamas and across the NW Caribbean. An associated surface trough has developed in the past 24 hours and extends from 31N73W through the central Bahamas and is moving slowly NW. Scattered moderate to strong convection is seen within 180 nm to the SE of this trough N of 27N. 1025 mb high pressure is centered just NE of Bermuda and extends SSW to Hispaniola. This is producing a tight pressure gradient to the E of the trough across the Bahamas and is producing fresh tradewinds S of 23N between 60W and 75W. Seas across this area are 8 to 10 ft in NE swell. To the east a surface trough is along 55W-56W from 18N to 25N, and is the surface remnants of Victor. Moderate winds prevail on either side of the trough for 300 nm. Moderate to fresh trade winds prevail elsewhere across the eastern tropical Atlantic E of 48W to the Cabo Verde Islands, to the south of 23N. Saharan air is seen dominated this zone north of 14N between the African coast and the tropical wave along 48W. Large NW to N swell generated by Sam is moving through the waters E of 60W, producing seas of 7 to 10 ft. The Cumbre Vieja volcano, that is on the island of La Palma in the Canary Islands, has been erupting almost continuously since 19 September at 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/. The high pressure NE of Bermuda will slide ENE throughout the week supporting fresh to strong winds across the central Caribbean through Thu. Winds and seas will then diminish significantly early Fri through Sun as the trough currently along 55W-56W shifts westward across the region and weakens. Moderate N to NE swell from Sam will gradually fade across the tropical Atlc waters through Wed night. $$ Stripling