000 AXNT20 KNHC 211020 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 620 AM EDT Sun Jun 21 2020 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 32N. The following information is based on satellite imagery, weather observations, radar and meteorological analysis. Based on 0600 UTC surface analysis and satellite imagery through 1020 UTC. ...TROPICAL WAVES... The axis of a tropical wave is near 27W south of 17N, moving W near 20 kt. Scattered moderate convection is within 210 nm of the wave axis from 09N-11.5N. There is no convection north of 12N due to the presence of the Saharan air layer, which is characterized by a dry and stable air mass with a dense area of Saharan dust. The axis of a tropical wave is near 50W south of 17N, moving W near 20 kt. Scattered moderate showers and isolated tstorms are within 270 nm of the wave axis from 05N-10N. A stable air mass associated to the Saharan air layer is limiting convection N of 10N. The axis of a tropical wave is near 72W, moving W near 20 kt. Isolated moderate convection is near the wave axis from 15N-17N. The axis of a tropical wave is near 86W south of 20N, moving W at 10 kt. Isolated moderate convection is seen south of 16.5N and west of 84W. ...MONSOON TROUGH/ITCZ... The monsoon trough extends from 12.5N16.5W to 10N22W. The ITCZ continues from 10N22W to 09.5N25.5W. It resumes from 09N29W to 07N48W, and from 07N53W to 06N57W. Aside from convection mentioned in the tropical waves section above, scattered moderate convection is within 180 nm N of the ITCZ between 30W-46W. Similar convection is within 180 nm of the ITCZ west of 53W. GULF OF MEXICO... A 1018 mb surface high is centered over the NE Gulf of Mexico near 28N86W. Scattered showers and isolated tstorms are seen over the SE Gulf of Mexico to the N of Cuba and over the Florida Straits. Gentle to moderate winds prevail over much of the Gulf waters, except in the vicinity of the high pressure center where light to gentle winds prevail. Surface ridging will prevail over the Gulf waters through the forecast period. Gentle to moderate easterly winds and slight seas are expected today. Moderate to fresh southerly winds are forecast over the western Gulf Mon night through Thu night as the pressure gradient tightens between the ridge and lower pressure over Mexico. CARIBBEAN SEA... As typical for this time of year, tropical waves are traversing the Caribbean waters. Please see the tropical waves section above. Strong to near gale force winds prevail across the south central Caribbean. Moderate to fresh winds prevail elsewhere across the Caribbean, except for the far NW Caribbean where gentle to moderate winds prevail. Isolated tradewinds showers are noted over the Caribbean waters. The GOES-16 Saharan Air Layer tracking product shows that a large, westward-moving plume of dense Saharan dust is moving across the eastern Caribbean Sea. The leading edge of this plume has reached 64W and is expected to continue spreading westward. Fresh to strong trades over the south-central Caribbean will expand to the north-central and southwest basin through the middle of the week as high pressure builds over the western Atlantic. Winds will pulse to near gale force near the coast of Colombia each night through Thu night with seas building to near 12 ft with the strongest winds. Fresh to strong winds are expected in the Gulf of Honduras tonight through Thu night. ATLANTIC OCEAN... Scattered moderate convection is noted from 26N-32N between 62W- 70W. Isolated moderate convection is also seen east of the coast of central Florida. A surface trough extends from 32N48W to low pressure of 1020 mb near 31N51W to 25N56W. Scattered moderate isolated strong convection is within 300 nm east of the trough. A large plume of Saharan dust continues to spread across the tropical waters. The Saharan dust appears to be particularly dense from 10N-20N between 40W-60W, with a second surge seen between Africa and 30W. Moderate to fresh tradewinds prevail south of 20N. Gentle to moderate winds prevail N of 20N. High pressure will prevail across the offshore waters of the western Atlantic Ocean through the next week. Fresh to occasionally strong easterly winds will pulse north of Hispaniola at night through Thu night. $$ AL/Hagen