000 AXNT20 KNHC 221758 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 158 PM EDT MON AUG 22 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 1200 UTC surface analysis and satellite imagery through 1715 UTC. ...SPECIAL FEATURES... Tropical depression Fiona is centered near 24.6N 59.7W at 22/1500 UTC or about 430 nm north-northeast of the northern Leeward Islands, or 535 nm south-southeast of Bermuda moving west- northwest at 15 kt. Estimated minimum central pressure is 1008 mb. Maximum sustained wind speed is 30 kt with gusts to 40 kt. Clusters of moderate to strong convection are within 90 nm of the center. Please see latest NHC Forecast/Advisory under the AWIPS/WMO headers MIATCMAT1/WTNT21 KNHC for more details. A tropical wave is in the east Atlantic with an axis extending from near 16N27W to 06N27W, moving west at 15 kt over the last 24 hours. The wave is associated with a 1010 mb low that is centered near 12N27W. Scattered moderate convection is from 09N to 16N between 26W and 31W. Environmental conditions are conducive for development, and a tropical depression is likely to form later today while the system moves westward to west- northwestward over the eastern tropical Atlantic Ocean. ...TROPICAL WAVES... A tropical wave is over the Central Atlantic with an axis extending from near 19N49W to 08N49W, moving westward at around 15 kt. This wave is accompanied by a 1010 mb low near 15N49W. Scattered moderate convection is from 13N to 20N between 48W and 54W. Isolated moderate convection is from 08N to 12N between 46W and 50W. Environmental conditions appear somewhat favorable for additional development of this system over the next several days. A tropical wave is over the western Caribbean and Central America with an axis extending from near 21N84W to 087N85W, moving westward at 15 to 20 kt. This wave is embedded in subtle 700 mb troughing. Scattered thunderstorms are within 240 nm of the wave axis south of 17N. ...ITCZ/MONSOON TROUGH... The Monsoon Trough extends across Africa into the east Tropical Atlantic near 16N17W through the 1010 mb special feature low near 12N27W to 08N38W. The ITCZ begins near 09N51W and continues over the coast of South America near 07N58W. Other than convection associated with the special feature low and tropical waves, clusters of moderate to strong convection are from 11N to 17N east of 20W to the coast of Africa. Isolated moderate convection is within 150 nm south of the monsoon trough axis west of 28W. ...DISCUSSION... GULF OF MEXICO... Surface ridging extends across the northeastern Gulf anchored by a 1018 mb high near 28N87W. This ridge supports gentle winds over the northeastern Gulf, and mainly moderate east to southeasterly winds over the remainder of the Gulf. A surface trough is over the southwestern Gulf extending from 24N95W to 18N96W. Scattered moderate convection and thunderstorms are south of 23N west of 95W. Over the next 24 hours the northern portion of a tropical wave will support additional convection over the Bay of Campeche. CARIBBEAN SEA... A tropical wave is over the western Caribbean. Please refer to the tropical waves section for more details. The pressure gradient between high pressure over the western Atlantic and lower pressures over Colombia supports fresh to strong winds from 11N to 16N between 69W and 82W. Mainly moderate trade winds prevail elsewhere over the Caribbean basin. Scattered thunderstorms are occurring S of 10N west of 80W associated with the eastern Pacific monsoon trough. Isolated thunderstorms are along the southern coast of Hispaniola and over the Gulf of Honduras. Otherwise, the Caribbean is free of convection. Over the next 24 hours the western Caribbean wave will exit the basin. A tropical wave and associated low over the central Atlantic will affect the Leeward Islands beginning Tuesday night. ...HISPANIOLA... Fair weather prevails across the island today. Moisture is forecast to increase across the island this afternoon supporting showers and possible thunderstorms. Fair weather is forecast Tuesday. A tropical wave and associated low will bring an increase in moisture to the region beginning Wednesday night. ATLANTIC OCEAN... Tropical depression Fiona and a tropical wave over the eastern Atlantic are the main features across the basin. Please see the Special Features section above for more details. The other feature of interest in the basin is a tropical wave in the central Atlantic with possibilities of becoming a tropical cyclone late this week. Please refer to the Tropical Waves section for more details. A 1019 mb center of high pressure is located near 26N75W. The remainder of the area is dominated by a surface ridge anchored by a 1029 mb high centered near 40N38W. For additional information please visit http://www.hurricanes.gov/marine $$ LATTO