000 AXNT20 KNHC 021037 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 637 AM EDT FRI SEP 2 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 0600 UTC surface analysis and satellite imagery through 1030 UTC. ...SPECIAL FEATURES... T.S. Hermine is centered near 30.8N 83.6W at 02/0900 UTC or about 35 nm east of Apalachicola, Florida and about 44 nm northeast of Tallahassee, Florida moving north-northeast at 12 kt. Estimated minimum central pressure is 988 mb. Maximum sustained wind speed is 60 kt with gusts to 75 kt. Numerous moderate convection is from 27N-33N between 77W-85W affecting the Florida Peninsula, southeast CONUS and the west Atlantic. Scattered showers and thunderstorms are from 25N-29N east of 88W affecting the eastern half of the Gulf of Mexico. Please see the latest NHC Intermediate Public Advisory under AWIPS/WMO headers MIATCPAT4/WTNT34 KNHC and the full Forecast/Advisory under the AWIPS/WMO headers MIATCMAT4/ WTNT24KNHC for more details. T.S. Gaston is centered near 38.5N 34.5W at 02/0900 UTC or about 274 nm west of Faial Island in the central Azores and about 348 nm west of Lajes Air Base in the Azores moving east at 13 kt. Estimated minimum central pressure is 992 mb. Maximum sustained wind speed is 55 kt with gusts to 65 kt. Scattered moderate convection is from 39N-42N between 30W-34W. Please see the latest NHC Forecast/ Advisory under the AWIPS/WMO headers MIATCMAT2/WTNT22 KNHC for more details. ...TROPICAL WAVES... A tropical wave is moving across the eastern Atlantic with axis extending from 21N22W to a 1011 mb surface low near 16N23W to 10N23W. This wave is well depicted in satellite imagery and global models. TPW imagery shows the wave embedded in a area of abundant moisture between 09N-20N. Isolated moderate convection is observed in the vicinity of the wave and low from 12N-16N between 21N24W while scattered moderate convection prevails across the southern portion of the wave between 19W-28W. A tropical wave is moving across the central Atlantic with axis from 20N41W to 09N42W, moving west near 20 kt over the past 24 hours. The wave coincides with a well defined 700 mb trough depicted by global models and is embedded within a surge of deep moisture as seen on the Total Precipitable Water imagery. Scattered moderate convection is from 13N-18N between 41W-47W. ...ITCZ/MONSOON TROUGH... The Monsoon Trough extends across Africa into the east Tropical Atlantic near 1716N23W to 11N37W to 10N53W. The ITCZ begins near 10N53W and continues to near 09N60W. Scattered moderate convection prevails within 200 nm south of the Monsoon Trough between 18W-40W. ...DISCUSSION... GULF OF MEXICO... The primary concern across the basin is T.S. Hermine which is moving over northern Florida at this time. For more information, please refer to the section above. A surface trough extends across the Bay of Campeche from 19N94W to 24N92W with isolated showers. Another surface trough extends across the central Gulf waters from 25N91W to 27N88W. Scattered moderate convection is observed south of this trough mainly east of 91W. Scatterometer data depicts gentle to moderate easterly winds west of 85W while moderate to fresh winds prevail east of 85W except north of 28N where T.S. Hermine is enhancing winds and seas. Expect for Hermine to continue moving northeast during the next 24 hours across the Florida Panhandle and southeast CONUS. Winds and seas will decrease over the Gulf waters by this evening through Saturday. CARIBBEAN SEA... An upper-level low is centered over the central Caribbean near 16N78W enhancing isolated convection across the waters north of 14N and west of 76W. Scattered moderate convection is moving across the waters north of Colombia mainly south of 13N between 74W-79W. To the east; a surface trough extend from the Atlantic to the U.S. Virgin Islands region near 19N65W with isolated convection. Another surface trough extends over the southeast Caribbean from 15N64W to 11N65W. Scattered moderate convection is related to this trough currently observed from 11N- 14N between 64W-67W. Scatterometer data depicts moderate to fresh trades across the basin. Expect through the next 24 hours for the surface troughs to continue moving west with convection. A tropical wave will enter the east Caribbean by late Saturday. ...HISPANIOLA... Fair weather prevails across the island at this time. The surface trough over the Virgin Islands will continue moving westward bringing moisture to the island today supporting isolated showers and thunderstorms. ATLANTIC OCEAN... T.S. Gaston continues moving northeast toward the northern Azores Islands. See the Special features above for details. Two tropical waves are moving across the basin. Please refer to the section above for details. Scattered to numerous showers and thunderstorms generated by T.S. Hermine are north of 28N west of 77W. To the southeast; a surface trough extends from 22N64W to the Virgin Island region near 19N65W. Isolated convection prevails along this feature. A surface ridge prevails across the remainder of the basin anchored by a 1021 mb high near 27N64N and a 1023 mb high near 29N46W. T.S. Hermine is expected to continue moving inland across northern Florida and along the southeast CONUS through the next 24 hours before entering the northwest Atlantic by late Saturday. Strong southerly winds and high seas will develop over the west Atlantic as the system moves through. Little change is expected elsewhere. For additional information please visit http://www.hurricanes.gov/marine $$ ERA