000 AXNT20 KNHC 192312 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 0005 UTC Thu May 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 1800 UTC surface analysis and satellite imagery through 2300 UTC. ...MONSOON TROUGH/ITCZ... The monsoon trough passes through the coastal plains of Guinea near 10N14W to 07N20W. The ITCZ continues from 07N20W to 00N50W. Numerous moderate to strong convection is from 04N to 08N between 12W and 18W. GULF OF MEXICO... Numerous showers and thunderstorms are active far northwest Gulf currently, associated with a mesoscale convective vortex centered about 120 nm south of Galveston Island, Texas. Elevated platforms in the northwest Gulf reported winds to gale force for brief periods earlier this afternoon. Thunderstorms along the leading edge are advancing southward along the Tamaulipas coast, and off the coast of southwest and south-central Louisiana. Elsewhere, scatterometer and buoy data indicate fresh E to SE winds over the remainder of the Gulf, with pockets of strong winds noted over the north-central Gulf. Seas are 8 to 10 ft over the northern Gulf and up to 9 ft in the Straits of Florida, where fresh to occasionally strong E winds run counter to the eastward moving Florida Current. Seas are 5 to 7 ft elsewhere. For the forecast, showers and thunderstorms are expected continue across the NW and central Gulf of Mexico over the few days. These storms could produce frequent lightning, gusty winds and reduce visibility. Meanwhile, a strong ridge stretching from eastern seaboard to the NE Gulf will continue to dominate the Gulf waters the remainder of the week. The pressure gradient between the ridge and deepening low pressure across the Southern Plains and northern Mexico will result in fresh to strong SE winds and high seas across the Gulf region tonight through Sat. Seas will peak 10 to 13 ft on Thu and Fri in the Straits of Florida with 12 ft seas in the central Gulf on Fri. CARIBBEAN SEA... 1029 mb high pressure is centered off Carolina coast. This is producing a modest pressure gradient across the basin, with a small area of fresh to strong SE winds occurring off the central coast of Honduras and over the south- central Caribbean with moderate to fresh trades elsewhere. In the southwest Caribbean, the monsoon trough extends from a 1011 mb low pressure centered over northern Colombia near 11N73W westward to western Panama and southern Costa Rica. No significant showers or thunderstorms are noted at this time. For the forecast, the high pressure off the U.S. East Coast will continue to build across the western Atlantic. This will bring fresh to strong winds tonight across the central Caribbean through early next week. Fresh to strong winds will also occur in the lee of Cuba on Fri and the weekend. Expect fresh to strong easterly winds in the Gulf of Honduras mainly at night through Thu night. ATLANTIC OCEAN A stationary front reaches from 32N35W to 22N75W. Scattered showers and thunderstorms are active along the front east of 65W. Weak 1018 mb low pressure is analyzed near 30N60W. The gradient between the low pressure and 1029 mb high pressure off the Carolina coast is supporting fresh to strong NE to E winds south of 27N and west of the front, with 7 to 9 ft seas in open waters. Farther east, broad ridging centered east of the Azores is supporting moderate to fresh trade winds south of 18N with 5 to 7 ft. Moderate to fresh SE winds with 6 to 8 ft seas are noted between the 1018 mb low and the ridge. Elsewhere north of 18N gentle to moderate NE to E winds with 4 to 6 ft seas are observed, except for fresh to strong NE winds and 7 to 10 ft seas off Morocco. For the forecast west of 65W, the stationary front will weaken through Thu. Meanwhile, the pressure gradient between the high pressure off the eastern seaboard and the frontal boundary will support an area of fresh to strong easterly winds N of the front and W of 65W Wed through Fri. Seas will peak around 10 ft E of the Bahamas tonight through early Thu. $$ Christensen