000 AXNT20 KNHC 071734 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 133 PM EDT Mon Aug 7 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 1200 UTC surface analysis and satellite imagery through 1730 UTC. ...SPECIAL FEATURES... Tropical Storm Franklin is centered near 17.7N 85.1W at 07/1500 UTC or about 178 nm east of Belize City, moving west-northwest at 12 kt. Estimated minimum central pressure is 999 mb. Maximum sustained wind speed is 50 kt with gusts to 60 kt. Scattered to numerous moderate convection is from 13N-21N between 80W-88W. This activity is affecting portions of Central America, western Cuba, and the Yucatan Channel. See the latest NHC Intermediate Public Advisory under AWIPS/WMO headers MIATCPAT2/WTNT32 KNHC and the full Forecast/Advisory under AWIPS/WMO headers MIATCMAT2/ WTNT22 KNHC for more details. ...TROPICAL WAVES... A tropical wave is over the central Atlantic and extends its axis from 21N43W to a 1012 mb low near 15N45W to 10N45W, moving west at 10-15 kt. TPW imagery is depicting abundant moisture in the wave's environment. The low is providing focus for scattered moderate convection from 14N-17N between 40W-45W. A tropical wave is over the eastern Caribbean extending its axis from 19N63W to 08N64W, moving west at 10-15 kt. While the low- level moisture convergence remains ample about the axis, an upper-level low noted on water vapor imagery centered near 20N66W is the only area with isolated moderate convection at this time mainly north of 18N. ...ITCZ/MONSOON TROUGH... The monsoon trough extends from the African coast near 13N17W to 09N22W to 15N44W. The Intertropical Convergence Zone extends from 10N47W to 07N58W. Aside from convection associated with the tropical waves, scattered moderate convection is from 05N-09N between 20W-30W. ...DISCUSSION... GULF OF MEXICO... A surface ridge extends across the basin from the Atlantic. With this, fair weather prevails across the basin. Scatterometer data depicts gentle to moderate southeasterly winds across the basin. The development of T.S. Franklin is enhancing scattered moderate convection across the Yucatan Channel and western Cuba. Expect conditions to deteriorate across the southwest Gulf as Franklin approaches. The surface ridge will drift northward as this happens. CARIBBEAN SEA... The primary concern is Tropical Storm Franklin, currently centered over the northwest Caribbean. Franklin will move west-northwest toward the Yucatan peninsula during the next 24 hours. Please refer to the section above for more details. A dry tropical wave is moving across the eastern Caribbean. Despite the lack of convection at this time, this wave is expected to enhance some activity over Puerto Rico and Hispaniola during the next 24-36 hours. Refer to the section above for more details. Fair weather prevails across the remainder of the basin. Scatterometer data depicts moderate to fresh trades across the area east of 80W, with highest speeds south 14N between 71W-77W. ...HISPANIOLA... Fair weather prevails across the island at this time. An approaching tropical wave is expected to increase cloudiness and precipitation across the island during the next 24-36 hours. ATLANTIC OCEAN... A tropical wave/low are moving across the basin. Refer to the section above for details. An upper-level low is centered north of Puerto Rico near 20N66W. This feature is reflected at the surface as a trough that extends from 24N60W to 20N62W. Isolated showers are observed within 100 nm on either side of the trough. The remainder of the area is under the influence of a surface ridge, anchored by a 1023 mb high centered near 30N69W and a 1022 mb high located near 28N50W. For additional information please visit http://www.hurricanes.gov/marine $$ ERA