000 AXNT20 KNHC 241207 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 805 AM EDT Thu May 24 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 1145 UTC. ...SPECIAL FEATURES... A broad, stationary surface low pressure system centered over the southeastern Yucatan Peninsula is gradually becoming better defined. Although showers and thunderstorms, along with strong gusty winds, are confined primarily to the adjacent waters of the northwestern Caribbean Sea, gradual development of this system is expected during the next couple of days as it drifts northward near the Yucatan Peninsula. Environmental conditions are forecast to become more conducive for development through early next week, and a subtropical or tropical depression is likely to form by late Saturday over the southeastern Gulf of Mexico. Regardless of development, locally heavy rainfall is forecast across western Cuba and over much of Florida and the northern Gulf Coast into early next week. In addition, the threat of rip currents will steadily increase along the Gulf coast from Florida westward to Louisiana over Memorial Day weekend. The chance for tropical cyclone formation during the next 48 hours is medium. The chance for tropical cyclone formation during the next 5 days is high. ...TROPICAL WAVES... A tropical wave is along 47W from 0N to 10N moving westward at 10 to 15 knots. This wave is associated with a sharp 700 mb trough. Scattered showers are within 290 nm west of the wave axis. ...MONSOON TROUGH/ITCZ... The monsoon trough extends from 11N15W to 04N20W. The ITCZ continues from 04N20W to 00N33W to 01N46W. The ITCZ continues W of the tropical wave from 01N48W to the coast of Brazil near 00N50W. Scattered moderate convection is within 190 nm N of the ITCZ between 20W-30W, within 290 nm S of the ITCZ W of 28W and from 01N-07N between 04W-20W. ...DISCUSSION GULF OF MEXICO... A surface ridge extends from an Atlantic 1027 mb high centered near 32N40W to the NE Gulf of Mexico. 10-15 knot E to SE winds are over the Gulf. An upper level trough is over the Gulf of Mexico with axis along 90W. Upper level moisture is over the Gulf, except over the SW Gulf where strong subsidence is noted. Isolated moderate convection is over the central Gulf from 24N- 27N between 85W-91W. More isolated moderate convection is over the NW Gulf from 25N-31N between 91W-95W. A broad surface low over the Yucatan peninsula is expected to intensify as it moves slowly northward toward southern Louisiana through Sun. Strong winds and building seas are expected east of the low center. CARIBBEAN SEA... Please read the Special Features section above. A 1010 mb low is centered over the Yucatan Peninsula near 19N88W drifting NW. Scattered moderate convection is over most of the Yucatan Peninsula. Scattered moderate convection is over the NW Caribbean Sea from 18N-22N between 82W-88W. Widely scattered moderate convection is inland over Central America from Quatemala to Panama. Elsewhere, 15-20 knot tradewinds are over the central and E Caribbean. An upper level trough is over the NW Caribbean N of 15N and W of 80W. An upper level ridge is over the remainder of the Caribbean. Upper level moisture is over the Caribbean, except over the Leeward and Windward Islands where strong subsidence is noted. High pressure in the central Atlantic will maintain fresh to locally strong trade winds in the Caribbean into Sat, with the strongest winds along the coast of Colombia. A broad surface low over the Yucatan peninsula will drift northward into the Gulf of Mexico through Fri. Fresh SE winds and building seas are expected the NW Caribbean Fri and Sat as the low develops. ATLANTIC OCEAN... Scattered showers are over the Bahamas. A 1029 mb high is centered over the central Atlantic near 32N39W producing fair weather. A large upper level low is centered NE of the Leeward Islands near 25N52W. Scattered showers are within 180 nm of the low. Moderate to fresh trade winds are expected over the W Atlantic south of 27N through Sat. An area of low pressure developing in the Gulf of Mexico will increase SE winds west of 77W to include the N Bahamas this weekend. For additional information please visit http://www.hurricanes.gov/marine $$ Formosa/Ramos