000 AXNT20 KNHC 031200 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 800 AM EDT Thu May 3 2018 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 1100 UTC. ...MONSOON TROUGH/ITCZ... The monsoon trough extends from 07N12W to 01N25W. The intertropical convergence zone continues from 01N25W to 00N51W. Scattered moderate convection is noted from 02N to 04N between 10W and 15W, and within 150 nm either side of the ITCZ W of 37W. ...DISCUSSION... GULF OF MEXICO... A ridge extends westward just N of the Gulf coast. Moderate to fresh SE winds are expected to increase to fresh to strong by this afternoon between the ridge to the east and a trough over the southern Plains. Seas are generally 5 to 7 ft, but may briefly exceed 8 ft this morning. Winds and seas will diminish by this afternoon as the trough lifts out to the N. Across the Straits of Florida, E winds of 20-25 kt continue. Seas could reach 7 ft in this area by this afternoon due to the persistent long-fetch easterly flow across the Florida Current. Widely scattered showers continue between the Florida Keys and Cuba. The persist ridge will allow the fresh to strong winds to persist through late Thu with seas reaching 9 ft, before diminishing through early next week as the ridge weakens. A weakening surface trough over the SW Gulf and Bay of Campeche is moving westward. Winds have decreased to 10-15 kt this morning, but they will increase to 15-20 kt again this afternoon and evening. Elsewhere, moderate to fresh winds persist with 4 to 6 ft seas. Winds and seas will diminish across the Gulf through early next week as the ridge to the north weakens. CARIBBEAN SEA... Persistent high pressure north of the area is supporting fresh to strong trade winds across the south-central Caribbean with seas of 8 ft. Moderate to locally fresh trades are noted elsewhere. Expect increasing winds and building seas across the waters E of the Lesser Antilles first, then across the eastern Caribbean Thu night into Fri due to the pressure gradient between the ridge to the north and a developing surface trough moving across the Bahamas. This weather pattern will keep relatively low winds of 15 to 20 kt off the coast of Colombia, and 10 to 15 kt elsewhere over the western Caribbean. SHowers and thunderstorms are occurring from Haiti to ern Jamaica and over the adjacent waters. Moisture will remain high across east and central Cuba today while gradually spreading eastward across Hispaniola, keeping the likelihood of scattered to numerous showers and tstms due to a developing mid-/upper-level low near the Bahamas drifting southward across eastern and central Cuba to the north central Caribbean. This unstable weather pattern could persist through the remainder of the week over the eastern half of Cuba and parts of Hispaniola as the broad upper-low meanders over the same area. ATLANTIC OCEAN... A stationary front extends from 31N52W to 24N72W in the central Bahamas. The front becomes diffuse over central Cuba. A large area of multi-layer clouds with embedded showers and tstms is noted along the frontal boundary east of the Bahamas between 65W and 75W. Scattered tstms are also evident over the southeastern Bahamas, Turks/Caicos, and continuing southward to Hispaniola. Ship and buoy reports indicate winds of 20-25 kt have developed south of the front to near Hispaniola and west of 63W. Locally higher gusts will be possible in some of the stronger thunderstorms. A sharp upper-level trough extends from the north central Atlantic southward across Bermuda, to the waters north of the northern Bahamas. A large mid-/upper-level low is expected to develop over the central/southeastern Bahamas later today, and drift southward to eastern/central Cuba by late Friday. This pattern will support the development of the surface trough north of Hispaniola. Active weather spawned by the instability of the upper-low along with abundant moisture drawn northward in a fresh to strong SE wind flow will accompany the surface trough as it moves W through the Bahamas by late Fri and into the Florida peninsula Sat. Showers and thunderstorms will be possible across South Florida this weekend as well as over western Cuba. Fresh to strong NE winds are expected ahead of the trough, and fresh to strong SE winds will follow the trough, impacting mainly the waters S of 27N-28N and W of 65W. The remainder of the Atlantic is under the influence of a 1029 mb high pressure located over the Azores. This is supporting moderate to fresh trades across the deep tropics, where seas are reaching 6 to 8 ft in NE to E swell. For additional information please visit http://www.hurricanes.gov/marine $$ Stewart