000 AXNT20 KNHC 102349 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 805 PM EDT SAT SEP 10 2016 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. ...SPECIAL FEATURES... Tropical wave extends from 22N45W to a 1009 mb low near 14N46W moving west-northwest near 10 kt over the past 24 hours. The low remains embedded within the monsoon trough. Gale force winds are expected Sunday morning northeast of the low center. Please see the latest NWS High Seas Forecast under AWIPS/WMO headers MIAHSFAT2/FZNT02 KNHC for more details. The circulation with this system appears to be better defined today, but the thunderstorm activity near the center remains poorly organized. There is a high chance of tropical development over the next 48 hours. Please see the latest NWS Tropical Weather Outlook under AWIPS/WMO headers MIATWOAT/ABNT20 KNHC for more details. Clusters of scattered moderate to isolated strong convection are over a broad area from 10N-16N between 39W-54W and from 16N-20N between 38W-44W. ...TROPICAL WAVES... Tropical wave in the east Tropical Atlantic extends along 18W/19W from 9N-20N moving west near 10 kt over the past 12 hours. A weak 1012 mb low is just to the southwest of the wave, embedded within the monsoon trough, near 10N21W. Wave coincides with a 700 mb trough based on the global models and is embedded within a surge of moisture as seen on the Total Precipitable Water Imagery. Clusters of scattered moderate to isolated strong convection are from 10N-14N east of 21W to inland over west Africa. Tropical wave in the Caribbean extends along 80W/81W from 11N- 19N moving west 10 to 15 kt over the past 24 hours. Wave coincides with a 700 mb trough based on the global models and is between surges of moisture as seen on the Total Precipitable Water Imagery. Wave is also located beneath northerly upper flow with any convection or shower activity associated with that northerly flow or the monsoon trough that extends across the southwest Caribbean, not the wave. Tropical wave in the south Gulf of Mexico extends along 94W/95W from 21N to inland over Mexico into the east Pacific region moving west near 15 kt over the past 24 hours. Wave coincides with a 700 mb trough based on the global models and is embedded within an area of moisture as seen on the Total Precipitable Water Imagery. However, the wave is beneath an upper ridge and is not generating any convection or shower activity. ...ITCZ/MONSOON TROUGH... The Monsoon Trough extends across Africa into the east Tropical Atlantic near 13N17W and continues through the 1012 mb low southwest of the tropical wave to 10N24W 16N41W then through the 1009 mb low in the Special Features to 10N51W where the ITCZ begins and continues to inland over South America near 7N58W. Scattered moderate to isolated strong convection is from 5N-9N between 32W-41W. Small clusters of scattered moderate to isolated strong convection are from 6N-12N between 26W-36W. ...DISCUSSION... ...GULF OF MEXICO... An upper shortwave trough is over the west Gulf from east Texas to over Mexico near Tampico covering the area west of 93W generating scattered showers and isolated thunderstorms inland and along the immediate coast of Texas. The remainder of the Gulf is dominated by an upper ridge anchored along the north coast of of the Yucatan peninsula extending a ridge axis north over Georgia. A surface trough in the central Gulf extends along 89W/90W from the Mississippi Delta to 22N generating scattered showers and isolated thunderstorms from 22N-29N between 86W-90W. A weak exposed 1014 mb low is in the southeast Gulf near 24N84W with isolated showers and thunderstorms south of the low to over west Cuba between 82W-84W. A weak surface ridge extends from over the southeast CONUS into the Gulf of Mexico anchored by a 1019 mb high over south Georgia. The tropical wave will exit the Gulf early Sunday. The surface ridge will shift north by Monday, then persist through midweek. The surface trough will shift west to southeast Texas coast through Monday. The 1014 mb low will move west into the south/central Gulf by Tuesday. ...CARIBBEAN SEA... An upper ridge over the Gulf of Mexico covers the west Caribbean west of 74W. An upper low is centered along the north coast of the Dominican Republic near 19N70W extending an upper trough along 14N70W to west Colombia near 11N75W. A second upper ridge, anchored east of the Leeward Islands covers the remainder of the east Caribbean. Afternoon/evening scattered showers and isolated thunderstorms that have developed inland over Hispaniola, Cuba, and Jamaica have moved south with the northerly flow aloft. Similar showers and thunderstorms that developed over Puerto Rico have moved north with the southerly flow aloft, east of the upper trough. The monsoon trough extends from a weak 1010 mb low in the southwest Caribbean near 10N78w to across Costa Rica near 10N84W generating scattered showers and isolated thunderstorms south of 13N between 76W-83W to inland over Colombia to Costa Rica. The easterly trade winds have generated isolated showers and thunderstorms over the Caribbean north of 15N between 68W- 75W and from 13N-17N between 75W-82W. The tropical wave will exit the Caribbean early Monday. ...HISPANIOLA... Scattered showers and isolated thunderstorms have developed over the central portion of the inland this evening. Afternoon/ evening showers and thunderstorms are expected through the weekend. ...ATLANTIC OCEAN... A narrow upper trough extends from the Bahama islands near 25N77W to the North Carolina coast supporting a surface trough that extends from 32N77W along 28N78W to south Florida near Miami. A broad upper ridge dominates the remainder of the west Atlantic north of 24N. The upper trough centered along the north coast of the Dominican Republic covers the area south of 24N to over the Caribbean supporting a surface trough that extends from 23N66W to 20N70W and is generating scattered showers and isolated thunderstorms within 75 nm either side of the surface trough. The diffluent environment between the these upper features are generating scattered showers and possible isolated thunderstorms from 21N-27N between 70W-79W. The remainder of the Atlantic is dominate by a surface ridge anchored by a 1026 mb high near 34N40W and a 1024 mb high 34N62W. The surface trough associated with the upper trough over the southwest Atlantic/ north Caribbean will move west-northwest into the southeast Bahamas tonight through Sunday. The tropical wave in the Special Features will move northwestward for the next few days. For additional information please visit http://www.hurricanes.gov/marine $$ PAW