000 AXNT20 KNHC 121628 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1228 PM EDT Thu Oct 12 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 1545 UTC. ...SPECIAL FEATURES... Hurricane Ophelia is centered near 30.5N 35.6W at 12/1500 UTC or about 620 nm SW of the Azores moving N-NE at 2 kt. Estimated minimum central pressure is 978 mb. Maximum sustained wind speed is 80 kt with gusts to 100 kt. Scattered moderate convection is from 28N-33N between 30W-39W. See the latest Forecast/Advisory under AWIPS/WMO headers MIATCMAT2/WTNT22 KNHC for more details. ...TROPICAL WAVES... A tropical wave extends from 08N52W to 18N49W moving W at 15-20 kt. The wave coincides with 700 mb troughing between 46W-55W and a maximum in 850 mb relative vorticity along the wave axis near 13N. Scattered moderate and isolated strong convection is from 07N-18N between 43W-54W. A tropical wave extends from 04N77W to 12N76W moving W at 5-10 kt. This wave coincides with very subtle 700 mb troughing and 850 mb relative vorticity over western Colombia and eastern Panama on the southwestern periphery of a mid-level ridge anchored over the NE Caribbean Sea. Widely scattered moderate convection is from 08N-14N between 70W-81W. ...ITCZ/MONSOON TROUGH... The monsoon trough extends from the African coast near 09N13W to 07N17W. The Intertropical Convergence Zone axis extends from 07N17W to 07N25W to 07N38W to 09N49W. Aside from the convection associated with the tropical wave...isolated moderate convection is from 05N-14N between 11W-31W. ...DISCUSSION... GULF OF MEXICO... A stationary front extends from the Florida panhandle near 30N86W W-SW to 28N96W then S-SE to 19N94W. The northern portion of the front remains generally precipitation-free and relatively diffuse...however fresh to strong northerly winds are noted S of 25N W of the front with scattered showers and tstms occurring across this area. Farther east...a surface trough is analyzed from near the front across the Florida panhandle to 27N87W with only a few isolated showers possible from 25N-29N between 85W-91W. Otherwise...gentle to moderate NE winds prevail across the basin E of the front. The front is expected to become diffuse through Thursday night and remain as a surface trough boundary across the SW Gulf Friday. CARIBBEAN SEA... An upper level low is centered over the Florida Straits and portions of Cuba continuing to provide an overall lower pressure regime and weak pressure gradient pattern across the basin. W-SW winds aloft prevail W of 70W and are generating scattered showers and tstms S of 14N between 70W-84W...and from 15N-20N between 80W-89W. Farther south...a tropical wave along 77W is moving across the SW Caribbean and far western Colombia. Widely scattered showers and tstms are occurring in the vicinity of the wave S of 14N. Otherwise...latest scatterometer data depicts gentle to moderate trades across the basin. ...HISPANIOLA... Southwestern flow aloft prevails over the island this afternoon between an upper level low centered over the Florida Straits and an upper level anticyclone centered near 19N64W. Cloudiness will increase throughout the afternoon with scattered showers and isolated tstms expected through the late evening hours. ATLANTIC OCEAN... Hurricane Ophelia is detailed above. An upper level low is centered over the Florida Straits providing support for a surface trough analyzed from a 1009 mb low near 23N79W NE to 26N75W to 29N71W. Scattered showers and tstms are focused primarily west of the trough axis occurring from 23N-28N between 74W-82W. Farther east...a weaker surface trough is noted from 20N58W to 28N55W and is generating isolated showers and tstms from 18N-22N between 50W-57W. The remainder of the eastern Atlc outside of the influence of Hurricane Ophelia...is under the influence of surface ridging anchored by a 1022 mb high centered SW of the Iberian peninsula near 37N17W. For additional information please visit http://www.hurricanes.gov/marine $$ HUFFMAN