000 AXNT20 KNHC 292315 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 715 PM EDT Thu Aug 29 2019 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 18000 UTC surface analysis and satellite imagery through 2300 UTC. ...SPECIAL FEATURES... Hurricane Dorian is centered near 22.5N 67.7W at 29/2100 UTC or about 280 nm E of Mayaguana in the SE Bahamas, moving NW at 11 kt. Minimum central pressure is near 986 mb. Maximum sustained wind speed is 75 kt with gusts to 90 kt. Numerous moderate to strong convection extends out 90 nm in the northern semicircle and 60 nm southern semicircle. Scattered moderate convection extends out 180 nm in the northern semicircle, 300 nm SE quad, and 75 nm SW quad. The NW motion will continue through Friday. A W to WNW motion will begin Friday night and continue into the weekend. On this track, Dorian should move well east of the southeastern and central Bahamas tonight and Friday, approach the northwestern Bahamas Saturday, and move near or over portions of the northwest Bahamas on Sunday. Dorian is expected to strengthen into a major hurricane on Friday, and remain an extremely dangerous hurricane through the weekend. See the latest NHC forecast/advisory under AWIPS/WMO headers MIATCMAT5/WTNT25 KNHC or www.hurricanes.gov for more details. ...TROPICAL WAVES... An east Atlantic tropical wave is along 22W from 04N-21N, moving W around 10 kt. Scattered showers are noted within 150 nm of the wave axis. A central Atlantic tropical wave is along 50W from 05N-22N, moving W around 10-15 kt. Saharan dry air prevails in the wave's environment, inhibiting convection. ...MONSOON TROUGH/ITCZ... The monsoon trough passes through coastal Senegal near 14N17W to 11N30W to 13N45W to 11N52W. The ITCZ extends from 11N52W to the coast of Venezuela near 09N61W. Aside from the convection mentioned in the Tropical Waves section, scattered moderate to strong convection is seen over west Africa and offshore from 11N-24N between 12W-19W. GULF OF MEXICO... A stationary front extends from Cedar Key Florida to the Mouth of the Mississippi River. Isolated showers and tstorms are along the southern coast of Louisiana and over portions of the NW Gulf of Mexico. Isolated tstorms are also near and over the Yucatan Channel. Scattered showers and tstorms are over the Florida Peninsula. Mainly gentle winds are seen across the basin in the most recent ASCAT pass. A surface trough will form in the central Gulf of Mexico this weekend, with fresh E or NE winds expected in the northern Gulf during that time, accompanied by increased shower and tstorm activity. The surface trough will migrate to the western Gulf early next week. Meanwhile, Hurricane Dorian in the Atlantic is expected to approach Florida Sunday. Winds and seas could increase as early as Monday or Monday night in the far eastern Gulf just west of Florida due to Dorian's presence over the Florida Peninsula. CARIBBEAN SEA... Although the center of Hurricane Dorian is now 240 nm NNW of Puerto Rico, a trailing band of moderate to strong convection extends southward over Puerto Rico and the USVI and north of 17N between 64.5W-68W. Flash flood warnings are currently in effect for southeastern portions of Puerto Rico, and Flood Advisories are in effect for Vieques and Culebra as of 29/2200 UTC. Dorian will continue moving farther away from the Caribbean tonight. Refer to the section above for more details on this system. Upper level diffluence is enhancing scattered showers and tstorms over the adjacent waters south of Cuba and Cayman Islands from 18N-22N between 76W-86W. In the southwest Caribbean, the East Pacific monsoon trough is inducing scattered showers and tstorms south of 12.5N between 70W-84W, including the area within 30 nm offshore the NW coast of Venezuela and the N coast of Colombia. Fair weather prevails elsewhere from 13N-17N between 60W-82W. Latest scatterometer data depicts moderate to fresh trades in the central and eastern Caribbean with light to gentle winds elsewhere. During the next several days, moderate to fresh winds are expected across the east and central Caribbean, with gentle to moderate winds over the NW Caribbean. Seas should remain quiescent during the next several days across the basin. ATLANTIC OCEAN... Refer to the sections above for details on Dorian and the tropical waves in the Atlantic. A surface trough extends across the west Atlantic from 24N79W to 30N76W. Scattered showers and tstorms are noted from 23N-32N between 74W-80W. An upper-level low is just to the NW of Dorian, near and north of the SE Bahamas. Scattered showers and tstorms are seen from 23N-27N between 70W-73W. To the east, an upper- level low in the central Atlantic is inducing scattered showers and tstorms from 21N-31N between 48W-60W. The remainder of the basin is under the influence of a surface ridge, anchored by a 1021 mb high centered near 34N38W. Hurricane Dorian will move to near 25N70W by 2pm EDT Fri, 26.5N74W 2pm Sat, 27N78W 2pm Sun, and to the Florida coast near 27.5N80W 2pm Mon. Dorian is anticipated to become a major hurricane as early as Friday and remain that way until landfall. $$ Hagen