000 AXNT20 KNHC 251150 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 750 AM EDT Fri May 25 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 1130 UTC. ...SPECIAL FEATURES... A 1011 mb low along the eastern coast of the Yucatan peninsula near Chetumal at 19.5N 88.0W is drifting slowly northward over the eastern Yucatan Peninsula. The low is producing widespread shower and thunderstorm activity over the far northwest Caribbean west of 83W. Environmental conditions are forecast to become more conducive for development, and a subtropical or tropical depression or storm is likely to form during the weekend over the eastern or central Gulf of Mexico. Please see high seas forecasts issued by the National Weather Service for information on gale warnings associated with this system. An Air Force Reserve reconnaissance aircraft is scheduled to investigate the disturbance this afternoon, if necessary. 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 the Memorial Day weekend. For more information on these threats, please see products issued by your local weather office. The chance for tropical cyclone formation during the next 48 hours is high. The chance for tropical cyclone formation during the next 5 days is high. A gale warning is in effect in the meanwhile for the Gulf of Mexico starting 1200 UTC Sat May 26 within 90 nm E semicircle of 1006 mb low centered near 22.5N87W with 30 to 35 kt winds, and seas 8 to 11 ft. ...TROPICAL WAVES... A tropical wave is moving eastward at 10 to 15 kt through French Guiana with the axis extending northward to 12N. The wave is in a moderate moist environment that is supporting isolated showers within 150 nm either side of the wave axis. ...MONSOON TROUGH/ITCZ... The monsoon trough extends from the coast of Guinea, Africa near 11N14W and continues to 04N20W. The ITCZ continues from 04N20W to 00N30W to 00N50W. Scattered moderate to isolated strong convection is along the coast of W Africa from 02N to 08N between 10W and 20W. Isolated moderate convection is within 180 nm either side of the ITCZ. ...DISCUSSION GULF OF MEXICO... A surface trough extends from low pressure along the coast of the Yucatan peninsula northward to the 26N87W in the eastern Gulf of Mexico. Isolated moderate convection is within 120 nm east of the trough, and over the Straits of Florida, portions of Florida, and the N Gulf coast E of Texas. Mostly fair weather is over the W Gulf. Light to gentle winds are in the western half of the basin with seas in the range of 2 to 3 ft. The low over the Yucatan peninsula is expected to develop into a a tropical cyclone as it moves slowly northward through Mon. Gale conditions and seas around 12 ft are now expected starting Sat in the SE Gulf, spreading northward and reaching the N central Gulf through Mon. Winds and seas will diminish on Tue. Please read the Special Features section above. CARIBBEAN SEA... Moderate to fresh tradewinds are over the E Caribbean with mostly fair weather. Aside from the showers and thunderstorms mentioned above related to the low pressure over Mexico, scattered showers and thunderstorms are also active from the central coast of Colombia to near San Andres Island in the southwest Caribbean. A few trade wind showers are noted elsewhere. The surface low over the Yucatan peninsula will drift northward into the Gulf of Mexico today. Fresh to locally strong SE winds and peak seas near 8 ft are expected the NW Caribbean through Sat as this low potentially develops into a tropical cyclone. High pressure in the central Atlc will maintain fresh to strong trade winds in the Caribbean through Sat with strongest winds along the coast of Colombia before weakening somewhat on Sun through early next week. ATLANTIC OCEAN... Scattered showers are over the northern Bahamas. The remainder of the Atlantic is under the influence of a broad surface ridge centered by a 1026 mb high near 32N36W. This high is supporting moderate winds in the Bahamas Bank and Atlantic passages to the Caribbean. Over the W Atlantic moderate to fresh tradewinds are expected S of 27N through Monday. SE to S winds will increase to fresh to locally strong W of 77W Sat night through Sun night as developing low pres in the Gulf of Mexico tightens the pressure gradient. For additional information please visit http://www.hurricanes.gov/marine $$ Formosa