000 AXNT20 KNHC 192355 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 754 PM EDT Sat May 19 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 1800 UTC surface analysis and satellite imagery through 2300 UTC. ...SPECIAL FEATURES... An upper-level trough extends across the eastern Gulf of Mexico and western Caribbean, with a diffluent flow aloft prevailing across the Florida Peninsula and western Atlantic/Caribbean mainly east of the upper trough's axis. This pattern is drawing deep tropical moisture northward from the SW Caribbean between 77W and 83W and is supporting numerous moderate to isolated strong convection along this corridor. This activity is expected to continue through the weekend and early next week with heavy rainfall flooding possible over the land areas affected. ...TROPICAL WAVES... A central Atlantic tropical wave has an axis that extends from 13N51W to 04N53W, moving W at 5 to 10 kt. This wave has slowed down its forward motion over the past 24 hours and is expected to become diffuse east of the Caribbean over the next couple of days. Numerous showers and isolated moderate convection are within 300 nm of either side of the wave axis S of 10N. ...MONSOON TROUGH/ITCZ... The monsoon trough passes through the coastal sections of Senegal near 14N17W to 04N23W. The ITCZ continues from 04N23W to 01N35W to the Brazil coast near 01N49W. Besides the convection associated with the tropical wave, isolated moderate convection prevails from 01N to 05N E of 44W. ...DISCUSSION GULF OF MEXICO... An upper-level trough prevails across the eastern Gulf, with an axis along 85W. A diffluent flow east of the trough is bringing tropical moisture over the far east Gulf and western Atlantic waters affecting the Florida Peninsula and Florida Straits/Keys. A surface trough is depicted within this convection and extends from 27N80W to 23N82W. This activity is expected to continue through the weekend. A weak ridge axis extends across the remainder of the basin along 30N producing mainly gentle to moderate winds. The surface trough is expected move into the eastern Gulf through Sunday. The upper-level trough over the eastern Gulf will remain for several days, thus a similar wet pattern is expected through this period over the eastern Gulf. CARIBBEAN SEA... An upper-level trough extends over the eastern Gulf of mexico and western Caribbean. Upper-level diffluence on the eastern side of this trough is supporting scattered to numerous moderate convection across the Caribbean waters between 76W-84W. Broad high pressure over the subtropical Atlantic continues to support moderate to fresh tradewinds over most of the basin, except fresh to strong winds over the central Caribbean. Wave heights of 8 to 10 ft persist over the central Caribbean as confirmed by a recent satellite altimeter pass and current buoy data. Over the next couple of days, the upper-level trough will remain in place enhancing shower and thunderstorm activity over the western Caribbean. The surface ridging pattern over the Atlantic will persist, keeping a similar wind profile in place across the basin into early next week. ATLANTIC OCEAN... A diffluent flow aloft to the east of an upper-level trough currently over the eastern Gulf of Mexico, combined with a surface trough extending just offshore of NE Florida is supporting scattered to numerous moderate convection across Florida, the Bahamas, and Atlantic waters mainly west of 76W. High pressure centered over the N Central Atlantic spans the Atlantic waters east of Florida to the northwest African coast. An earlier afternoon scatterometer pass indicated fresh to locally strong southeast winds over a portion of the Bahamas as well as NE of Hispaniola, with these winds likely also occurring NW of Hispaniola. A recent altimeter pass indicates wave heights of 8 to 9 ft over these waters outside of the Bahamas. Moderate to fresh tradewinds are occurring elsewhere across the central and western Atlantic south of 27N. Gentle to moderate winds cover the central Atlantic north of 27N. Moderate to occasionally fresh north to northeast winds are occurring over the eastern Atlantic. The overall pattern will change little over the weekend. Therefore, the chances for heavy rainfall over the Florida Peninsula, Bahamas, and western Atlantic will continue. For additional information please visit http://www.hurricanes.gov/marine $$ Latto