000 AXNT20 KNHC 030010 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 810 PM EDT Wed Aug 2 2017 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 2315 UTC. ...TROPICAL WAVES... An eastern Atlantic tropical wave extends from 20N35W to 06N37W, moving west at 15 kt. SSMI TPW shows the wave is on the leading edge of a moist area. The Saharan Air Layer imagery shows dry air and dust NW of the wave axis, N of 14N. The 700 mb guidance from the GFS model also indicates broad troughing with this wave. Scattered showers are within 120 nm of the wave axis S of 14N. An eastern Caribbean tropical wave extends from 20N62W to 07N61W, moving west at 20 kt. SSMI TPW imagery shows a large area of moisture around this wave. The 700 mb guidance from the GFS model also depicts a large trough with this wave. The Saharan Air Layer imagery shows dry air and dust N of this wave, N of 20N. Scattered moderate convection is within 240 nm of the wave axis, S of 17N. Fresh to locally strong east to southeast winds accompany this wave as it moves across the eastern Caribbean. A western Caribbean Sea tropical wave extends from 19N87W to 07N84W, moving west at 20 kt. SSMI TPW imagery shows a large area of moderate moisture around this wave. The 700 mb guidance from the GFS model also depicts a small trough with this wave. The Saharan Air Layer imagery shows dry air and dust NE of this wave. Scattered moderate convection is over all of Honduras. Isolated moderate convection is elsewhere within 180 nm of the wave axis. ...ITCZ/MONSOON TROUGH... The monsoon trough axis extends from the west coast of African coast near 09N13W to 08N30W to 11N46W, where scatterometer data indicates the ITCZ begins and extends to 11N60W. Aside from the convection associated with the tropical waves, scattered moderate to strong convection is along the coast of W Africa from 08N- 13N between 11W-17W. Widely scattered moderate convection is from 05N-10N between 19W-29W. Isolated moderate convection is from 08N-11N between 39W-47W. ...DISCUSSION... GULF OF MEXICO... As of 2100 UTC, a surface trough extends from St Augustine Florida near 30N81W, to a 1015 mb low E of Tallahassee Florida near 30N83W, to a 1014 mb low over the NE Gulf of Mexico near 29N85W, to the north central Gulf near 27N90W, to the NW Gulf near 29N95W. Scattered moderate to isolated strong convection is within 120 nm either side of the trough. Elsewhere, scattered showers are over the Straits of Florida, W Cuba, and N Yucatan Peninsula. In the upper levels, a large upper level trough is centered over the N Gulf N of 28N supporting the surface trough. Expect in 24 hours for the latter surface low to move to SE Georgia with a surface trough extending SW to the NE Gulf, and the NW Gulf. Expect convection to continue over the N Gulf N of 26N from Florida to Texas. CARIBBEAN SEA... Two tropical waves are moving across the Caribbean. See above. In addition, scattered moderate convection is noted over the central Caribbean from 13N-17N between 70W-78W. In the upper levels, an upper level trough is centered Honduras enhancing convection. Expect the tropical waves to be the dominate weather features over the next 24 hours. ...HISPANIOLA... Scattered showers are over the southern portions of the island, moving W. This steering flow is due to an upper level high centered N of Hispaniola near 22N72W. Expect more showers and convection over S Hispaniola over the next 24 hours. ATLANTIC OCEAN... A tropical wave is moving across the Atlantic and another tropical wave is entering the Atlantic from W Africa. Scattered moderate convection is over the N Bahamas. A 1025 mb high is centered over the central Atlantic near 32N43W producing fair weather. Of note in the upper levels, an upper level trough is over the W Atlantic N of 27N and W of 65W. An upper level low is over the central Atlantic near 29N50W with cloudiness W of center. Another upper level low is centered over the E Atlantic near 27N37W. Expect in 24 hours for additional convection to be over the W Atlantic N of 27N and W of 75W. For additional information please visit http://www.hurricanes.gov/marine $$ Formosa