042 AXNT20 KNHC 281204 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 804 AM EDT Tue Aug 28 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. ...TROPICAL WAVES... An Atlantic Ocean tropical wave axis is along 25W/26W from 20N southward. A 1010 mb low pressure center is along the wave near 09N. Isolated moderate rainshowers are from 05N to 19N from 30W eastward. An Atlantic Ocean tropical wave is along 51W/52W from 20N southward. Isolated moderate rainshowers are from 10N to 19N between 48W and 60W. A Caribbean Sea tropical wave is along 67W/68W from 21N southward, through the Mona Passage to Venezuela. Upper level cyclonic wind flow covers the Atlantic Ocean from 20N to 27N between 60W and 70W. Isolated moderate rainshowers are from 16N to 24N between 60W and 70W. A tropical wave is along 88W/89W from 22N southward, from the Yucatan Peninsula through Belize, Guatemala, and El Salvador, into the eastern Pacific Ocean. Isolated moderate rainshowers are within 90 nm on either side of the tropical wave. ...MONSOON TROUGH/ITCZ... The monsoon trough passes through the coastal sections of Senegal near 14N17W, to the 1010 mb low pressure center that is along the 25W/26W tropical wave, to 09N34W and 10N40W. The ITCZ continues from 10N40W to 11N47W and 11N51W. Isolated moderate rainshowers are elsewhere from 20N southward from 60W eastward. ...DISCUSSION... GULF OF MEXICO... An upper-level trough extends from NE Florida to 23N83W. A ridge prevails over the basin from western Florida to southern Texas. Moist conditionally unstable air across the basin is enhancing scattered showers. The strongest activity is north of 24N between 86W and 92W. An upper low centered over central Cuba is also enhancing convection over the Florida peninsula. A surface trough will develop each evening over the Yucatan Peninsula before pushing offshore into the SW Gulf. A surge of moderate to fresh NE to E winds will accompany this trough. Otherwise, a ridge will dominate the Gulf waters supporting gentle to moderate winds. CARIBBEAN SEA... Two tropical waves are moving across the basin. Refer to the section above for details. An upper low centered over central Cuba near 20N81W, along with abundant tropical moisture, is inducing scattered showers across Cuba. Convective activity will gradually shift westward as the upper low tracks moves to the W. The eastern part of the eastern Pacific monsoon trough stretches across Panama to Colombia. Scattered showers and thunderstorms are south of 14N between 79W-86W. Fresh to strong winds will prevail in the south- central Caribbean through Wed before diminishing. Gentle to moderate winds will prevail elsewhere. ATLANTIC OCEAN... Two tropical waves are moving across the basin. See the section above for details. An upper low centered over the NW Caribbean is enhancing convection across the western Atlantic W of 77W. A surface trough is over Florida, and another trough was noted in scatterometer data from 31N43W to 28N48W. Surface high pressure will prevail through the forecast period. For additional information please visit http://www.hurricanes.gov/marine $$ mundell/al/mt