000 AXNT20 KNHC 211754 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 105 PM 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 1200 UTC surface analysis and satellite imagery through 1700 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 180 nm of the wave axis from 08N-12N. 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 dense Saharan dust. The axis of a tropical wave is near 51W south of 15N, moving W near 20 kt. Widely scattered moderate convection is within 240 nm of the wave axis from 07N-13N. A stable air mass associated to the Saharan air layer is limiting convection N of 13N. The axis of a tropical wave is near 73W/74W south of 20N moving W near 20 kt. No convection is noted. The axis of a tropical wave is near 87W south of 20N moving W at 10 kt. Isolated moderate convection is seen south of 15N and west of 85W. ...MONSOON TROUGH/ITCZ... The monsoon trough extends from 11N15W to 09N20W. The ITCZ continues from 09N20W to 07N25W. It resumes from 07N28W to 07N50W and from 07N53W to 06N56W. Aside from convection mentioned in the tropical waves section, scattered moderate convection is within 180 nm N of the ITCZ between 30W-38W. Similar convection is within 180 nm of the ITCZ west of 53W. GULF OF MEXICO... A 1020 mb surface high is centered over the NE Gulf of Mexico near 28N85W. Isolated moderate convection is over central and south Florida, and over the Straits of Florida. 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. Scattered moderate to strong convection is over the SW Caribbean south of 13N between 76W-84W. 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. 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 66W 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... Isolated moderate convection is over the W Atlantic south of 29N between 74W-80W. A 1020 mb low is centered over the central Atlantic near 31N49W. A surface trough extends southwest from the low to 24N57W. Isolated moderate convection is within 360 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. $$ Formosa