000 AXNT20 KNHC 110500 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 100 AM EDT Fri Aug 11 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 0000 UTC surface analysis and satellite imagery through 0415 UTC. ...TROPICAL WAVES... A tropical wave extends from 06N35W to 14N34W moving W at 10-15 kt. The wave coincides with 700 mb troughing between 32W-40W. A 1012 mb low is embedded within the monsoon trough along the wave axis near 11N35W. Isolated moderate convection is from 06N-10N between 29W-35W. A tropical wave extends from 06N70W to 15N68W moving W at 10-15 kt. The wave coincides with 700 mb troughing between 66W-73W. Scattered moderate and isolated strong convection is from 06N- 12N between 71W-77W. A tropical wave extends from 09N89W to 18N88W moving W at 10-15 kt. The wave remains within the southern periphery of a mid-level ridge anchored over the Gulf of Mexico to the north. Scattered moderate convection is from 11N-18N between 84W-93W. ...ITCZ/MONSOON TROUGH... The monsoon trough extends from the African coast near 13N17W to 11N24W to 12N31W to 06N44W. The Intertropical Convergence Zone axis extends from 06N44W to 05N52W. Aside from convection associated with the tropical waves...widely scattered moderate convection is from 08N-14N between 15W-25W. ...DISCUSSION... GULF OF MEXICO... An upper level anticyclonic circulation is centered over the Rio Grande River valley near 29N100W and is providing much of the Gulf basin with N-NE upper level flow this evening. Water vapor imagery indicates moisture...cloudiness...and lingering widely scattered showers and isolated tstms across the SE CONUS and Gulf waters N of 28N as a result of maximized afternoon heating...instability... and diffluence aloft. Otherwise...a surface ridge anchored by a 1019 mb high centered near 29N87W continues to provide the remainder of the basin with relatively clear skies and fair conditions within gentle to moderate E-SE winds. The ridge is forecast to hold nearly stationary across the NE and north-central waters through the weekend as a surface trough weakens and becomes diffuse across the Florida peninsula. A few isolated showers and tstms are occurring this evening across interior portions of Florida and the adjacent coastal Gulf waters generally E of 84W. CARIBBEAN SEA... An upper level low is centered over the Gulf of Honduras and extends troughing NE over the NW Caribbean to eastern Cuba. In addition...a tropical wave is analyzed along 89W and both features continue to generate widely scattered showers and tstms across portions of Central America and the SW Caribbean generally S of 17N W of 79W...and across the Yucatan Channel region and adjacent coastal waters of Cuba N of 20N. The upper level low is forecast to move west and weaken over Central America while the tropical wave moves into the East Pacific region through Friday. Farther east...another tropical wave is along 69W and continues providing isolated shower activity to the south-central waters and ABC islands this evening. The wave will move west and bring an increased probability of convective precipitation to northern Colombia and the SW Caribbean through Saturday. Elsewhere... moderate to fresh trades prevail with a few isolated showers occurring across Trinidad and Tobago and the extreme southern Windward Islands. ...HISPANIOLA... A few isolated showers and tstms linger across SW portions of the island this evening...however mostly clear skies and fair conditions prevail elsewhere and are expected through Friday. ATLANTIC OCEAN... A mid-level weakness between ridging anchored over the northern Gulf of Mexico and a ridge in the vicinity of 29N77W is noted on water vapor imagery over the Florida peninsula supporting a surface trough analyzed from 26N81W to 31N79W. The surface feature along with middle to upper level divergence is generating widely scattered showers and tstms N of 23N W of 77W...including portions of the southern Florida peninsula this evening. The surface trough is forecast to remain across Florida through the weekend and become diffuse by Sunday night. Farther east...a broad middle to upper level low is centered NE of Puerto Rico near 24N62W. A 1014 mb surface low is nearly collocated with the upper level feature near 22N62W with a surface trough extending from near Anguilla in the Leeward Islands through the low center to 24N60W. Scattered showers and tstms are focused within 90 nm of the low center. The upper level feature supports widely scattered showers and isolated tstms from 24N-28N between 55W-64W. Finally...another upper level low is centered near 29N39W and supports a weakening 1016 mb low centered near 30N40W. A surface trough extends SW from the low to 25N50W with isolated showers possible within 90 nm of the low center and within 90 nm either side of the trough axis. For additional information please visit http://www.hurricanes.gov/marine $$ HUFFMAN