000 AXNT20 KNHC 131020 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 620 AM EDT Fri Oct 13 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 0600 UTC surface analysis and satellite imagery through 1015 UTC. ...SPECIAL FEATURES... Hurricane Ophelia is centered near 31.1N 33.9W at 13/0900 UTC or about 534 nm southwest of the Azores, moving east-northeast at 7 kt. Estimated minimum central pressure is 970 mb. Maximum sustained wind speed is 90 kt with gusts to 110 kt. Numerous moderate convection is from 29N-33N between 30W-35W. See the latest Forecast/Advisory under AWIPS/WMO headers MIATCMAT2/WTNT22 KNHC for more details. ...TROPICAL WAVES... A tropical wave is over the east Atlantic extending its axis from 16N25W to 04N25W, moving west at about 10-15 kt. The wave is in a region of strong vertical shear and IR enhanced imagery shows that the wave is being affected by Saharan dry air and dust. At this time, the only area with scattered moderate convection is located along 09N, where the wave interacts with the monsoon trough. A tropical wave is in the central Atlantic with axis extending from 21N53W to 09N57W, moving west at 10-15 kt. The wave is mainly in a low to moderate vertical shear environment and TPW imagery depicts the wave is in a region of abundant moisture. Mid- level diffluence and upper-level divergence support scattered moderate convection from 10N-20N between 48W-59W. A tropical wave is in the Caribbean with axis extending from 13N80W to 03N80W, moving west at about 5 kt. The wave is mainly in a low to moderate vertical shear environment and TPW imagery shows the wave in a region of abundant moisture. At this time, scattered moderate convection is observed along the southern portion of the wave where it interacts with the monsoon trough mainly south of 10N. ...ITCZ/MONSOON TROUGH... The monsoon trough extends across inland Africa to 10N14W to 09N28W. The ITCZ extends from 09N28W to 10N53W. Aside from the convection associated with the tropical waves, scattered moderate convection is within 100 nm on either side of the ITCZ between 35W-46W. ...DISCUSSION... GULF OF MEXICO... A stationary front extends from the Florida panhandle near 30N86W to 26N92W, then weakens from that point to 20N96W. Isolated showers are noted along the front. A surface trough extends across the Bay of Campeche from 23N93W to 18N94W. Scattered moderate convection prevails south of 20N between 92W-97W. An upper-level low is over the west Atlantic reflected as at the surface as a trough and generating scattered showers across the southern portion of the Florida Peninsula and adjacent waters mainly south of 25N and east of 87W. Gentle to moderate easterly winds prevail across the basin east of the front. The front is expected to become diffuse and remain as a surface trough across the southwest Gulf on Friday. CARIBBEAN SEA... A mid-to-upper level low is centered over the Bahamas and extending its trough across Cuba and the far northwest Caribbean. At the surface, a 1010 mb low is centered near 23N82W with trough extending from the low to 17N83W. Isolated showers are noted with these features. A low amplitude tropical wave is moving across the south-central Caribbean. See the section above for details. Latest scatterometer data depicts gentle to moderate trades across the basin. Expect for the low over Cuba to move west during the next 24 hours. ...HISPANIOLA... Fair weather prevails across the island at this time. A mid-to- upper level high will be over the island through Saturday, thus supporting fair weather. ATLANTIC OCEAN... Hurricane Ophelia is detailed above. Two tropical waves are moving across the basin. Refer to the section above for details. An upper-level low is centered over the northern Bahamas providing support for a surface trough analyzed from 29N75W to 23N78W with scattered showers and thunderstorms focused primarily west of 73W. Farther east, another surface trough is noted from 30N55W to 22N60W with no significant convection. A 1018 mb surface high is centered near 29N50W. The remainder of the eastern Atlantic outside of the influence of Hurricane Ophelia is under the influence of surface ridging anchored by a 1022 mb high centered near 38N19W. For additional information please visit http://www.hurricanes.gov/marine $$ ERA