000 AXNT20 KNHC 190003 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 803 PM EDT Fri May 18 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. ...TROPICAL WAVES... A central Atlantic tropical wave has an axis that extends from 12N48W to 00N50W, moving W at 10 to 15 kt. This wave appears as a poleward surge in low-level moisture and troughing at 700 mb. This wave however has been become somewhat ill defined over the past 24 hours. No significant convection is noted at this time. ...MONSOON TROUGH/ITCZ... The monsoon trough passes through the coastal sections of Guinea near 10N13W to 04N30W. The ITCZ continues from 04N30W to 06N45W. Besides the convection associated with the tropical wave, scattered moderate and isolated strong convection is from 00N to 07N between 04W and 23W. ...DISCUSSION GULF OF MEXICO... An upper-level trough with axis along 87W is interacting with a deep plume of tropical moisture to the east of the trough axis to produce scattered to numerous showers and embedded thunderstorms mainly east of 84W affecting the Florida peninsula, Florida Straits, and the majority of Cuba. A weak ridge axis extends across the remainder of the basin along 25N producing mainly gentle to moderate winds. A new surface trough will develop just east of South Florida this weekend and move into the eastern Gulf by Sunday. The upper-level trough over the eastern Gulf will remain for several days, and will continue to be the focus for shower and thunderstorm activity mainly over the far eastern Gulf, where deeper moisture and better lift will prevail. CARIBBEAN SEA... An upper-level trough extends over the Yucatan Channel and the northwest Caribbean. Upper-level diffluence on the eastern side of this trough is supporting scattered moderate convection N of 16N between 73W and 87W, and south of 14N east of 76W. Broad high pressure over the subtropical Atlantic continues to support moderate to fresh tradewinds over the NW and E Caribbean, and fresh to strong winds over the central Caribbean. Light winds are occurring over the extreme SW Caribbean near the eastern Pacific monsoon trough. Wave heights of 8 to 10 ft continue to occur over the S central Caribbean as confirmed by an 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 the upcoming weekend. ATLANTIC OCEAN... A diffluent flow aloft to the east of an upper-level trough currently over the eastern Gulf of Mexico is supporting scattered moderate convection across Florida, the Bahamas, and Atlantic waters mainly west of 74W. To the east, a 1028 mb high is centered over the central Atlantic near 33N55W. A 1030 mb high is also over the central Atlantic near 34N37W. These centers anchor a very broad ridge that spans the Atlantic waters east of Florida to the northwest African coast. The pressure gradient between the central Atlantic high and lower pressures in the Caribbean and eastern Gulf of Mexico support fresh to locally strong easterly winds along the northern coast of Hispaniola and eastern Cuba. Moderate to fresh tradewinds are occurring across the central and western Atlantic south of 27N. Gentle to moderate winds cover the central Atlantic N of 27N. Moderate to occasionally fresh NE winds are occurring over the eastern Atlantic. The overall pattern will change little over the weekend, with ongoing convection possible west of 75W and strong winds expected to continue along the northern coast of Hispaniola, and at times eastern Cuba. For additional information please visit http://www.hurricanes.gov/marine $$ Latto