000 AXNT20 KNHC 141025 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1205 UTC Wed Apr 14 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 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 1000 UTC. ...SPECIAL FEATURES... Windward Islands Ashfall Advisory: An Ashfall Advisory remains in effect for La Soufriere Volcano that is on the island of St. Vincent near 13.3N 61.2W. The volcano currently is undergoing occasional light emissions from its summit. The volcano could erupt at any time with little notice. Ash may be reaching the surface of the ocean, and low-level visibility may be reduced. Mariners who are transiting the waters near Saint Vincent should exercise caution. If you encounter volcanic ash or volcanic debris, please report the observation to the National Hurricane Center, at 305-229-4424. ...MONSOON TROUGH/ITCZ... The monsoon trough passes through the coastal sections of Guinea near 10N14W to 04N23W. The ITCZ continues from 04N23W to the equator near 38W. Scattered moderate to strong convection is from 03N to 09N between 12W and 19W. GULF OF MEXICO... A so-called backdoor cold front has pushed across the Florida peninsula into the far eastern part of the Gulf of Mexico. This frontal boundary will quickly dissipate over the eastern Gulf waters today. A squall line that developed near the coast of Louisiana last night produced strong thunderstorms and gusty outflow winds to 25-30 kt based on ASCAT and buoy data. The squall line convection has decreased significantly during the past several hours, with multi-layer debris clouds and a few lingering showers all that remains. A surface trough near the Yucatan penisula is enhancing winds in the south-central Gulf near 90W. The remainder of the basin is relatively cloud-free in broad-scale east to southeast moderate wind flow. A cold front will reach the northern Gulf Thu night, then stall and weaken on Fri. A strong cold front will move into the NW Gulf on Sat, with strong northerly winds and building seas expected across the western Gulf this weekend. CARIBBEAN SEA... A weak pressure gradient prevails over the Caribbean waters. Moderate winds prevail over much of the Caribbean waters, except fresh winds in the Gulf of Honduras. Seas are 2 to 3 ft across the northern Caribbean, including the Windward Passage, and 3-5 ft elsewhere. An Ashfall Advisory remains in effect for La Soufriere Volcano on St. Vincent near 13.3N 61.2W. Mariners transiting the nearby waters should exercise caution. Moderate to fresh trade winds will prevail across the Caribbean through Sat. SE winds will increase in the NW Caribbean Fri night and Sat. Gentle to moderate winds are expected elsewhere. ATLANTIC OCEAN... A pair of cold fronts are moving across the western Atlantic waters. The primary cold front extends from a 1002 mb low near 32N54W to north of Hispaniola and Puerto Rico near 20N68W. Widespread showers are noted north of 22N east of the front to 50W, and scatterometer data shows fresh SW winds east of the frontal boundary. A second cold front, from reinforcing cool air, is analyzed from a 1003 mb low near 33N62W to 26N68W across the Bahamas to the Florida Keys near 25N81W. Fresh to strong northerly winds are associated with the front. Isolated showers are noted along this secondary front. Seas are 8 to 11 ft north of the secondary front, and 8-9 ft along the primary frontal boundary. Elsewhere, a broad weak 1019 mb area of high pressure is centered in the tropical eastern Atlantic near 26N30W. Seas are generally 5 to 7 ft across the Atlantic, except 3-4 north of the Greater Antilles. An Ashfall Advisory remains in effect for La Soufriere Volcano on the island of St. Vincent near 13.3N 61.2W. The volcano remains in an active state of unrest, and could erupt erupt at any time with little notice. Mariners transiting the Tropical N Atlantic waters east of the Windward Islands should be aware of the possibility of volcanic ash reaching the ocean surface. The weakening cold front north of Hispaniola and Puerto Rico will move eastward through tonight. Fresh northerly winds associated with reinforcing cold air north of the Bahamas between 68W and 75W will shift eastward today and weaken. Another cold front will move east of northern Florida into the northern waters on Fri, then stall north of the Bahamas this weekend. $$ Mundell