000 AXNT20 KNHC 141626 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1226 PM EDT Mon Aug 14 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 1200 UTC surface analysis and satellite imagery through 1545 UTC. ...SPECIAL FEATURES... Tropical Storm Gert is centered near 30.3N 72.2W at 14/1500 UTC or about 400 nm WSW of Bermuda moving N at 7 kt. Estimated minimum central pressure is 1002 mb. Maximum sustained wind speed is 50 kt with gusts to 60 kt. Scattered to numerous moderate convection is from 26N-31N between 69W-75W. See latest NHC forecast/advisory under AWIPS/WMO headers MIATCMAT3/WTNT23 KNHC for more details. ...TROPICAL WAVES... A tropical wave extends from 14N26W to 23N23W moving W at 10-15 kt. The wave coincides with 700 mb troughing between 21W-29W and a maximum in 850 mb relative vorticity at the southern extent of the wave embedded within the monsoon trough near 14N26W. The wave is expected to inject energy into a 1011 mb low embedded within the monsoon trough near 13N34W by Tuesday. Environmental conditions are expected to become more conducive for development of this low later in the week with a medium chance for tropical cyclone formation within 5 days. Widely scattered moderate convection is from 10N-15N between 25-31W. A tropical wave extends from 09N44W to 24N38W moving W at 20 kt. This wave is evident in low to mid-level satellite cloud wind vectors and coincides with 700 mb troughing between 40W-50W. Widely scattered moderate convection is from 06N-11N between 43W-49W. A tropical wave extends from 11N61W to 22N60W moving W at 15-20 kt. There is limited convection associated with this wave with only isolated moderate convection from 16N-19N between 60W-63W. A tropical wave extends from 10N91W to 17N90W and continues to move across Guatemala...southern Mexico...and the East Pacific waters. This wave is generating isolated moderate convection across the NW Caribbean Sea from 16N-20N between 79W-89W. ...ITCZ/MONSOON TROUGH... The monsoon trough extends from the African coast near 15N17W to 13N34W to 08N49W. The Intertropical Convergence Zone axis extends from 08N49W to 08N60W. Aside from the convection associated with the tropical waves...scattered moderate convection is from 03N-11N between 11W-20W...and from 08N-16N between 32W-41W. ...DISCUSSION... GULF OF MEXICO... A ridge of high pressure prevails across the Gulf this afternoon. The latest surface observations and scatterometer data indicates light to gentle southerly winds covering much of the basin. By Tuesday the pressure gradient is expected to strengthen across the western waters...resulting in gentle to moderate S-SE winds generally W of 92W. The ridge will remain in place across the Gulf waters the next several days with these general conditions prevailing. In addition...a thermal trough will develop each evening across the Yucatan Peninsula. The trough will shift westward into the SW Gulf waters during the overnight hours and dissipate across this area each morning. Locally higher winds can be expected west of the trough axis. CARIBBEAN SEA... Ridging across the central Atlc is beginning to build westward south of T.S. Gert which will strengthen the pressure gradient across the basin. Latest surface observations and scatterometer data indicates moderate to fresh winds across the south-central waters...and gentle to moderate winds elsewhere. By tonight... winds will increase fresh to strong across the south-central waters as Gert moves farther north. Overall...this will bring an increase in coverage of fresh winds across the central and eastern Caribbean through Wednesday night. ...HISPANIOLA... Expect daytime heating...local sea breezes...and mountain upslope lifting to produce scattered showers and tstms during the afternoon and evening hours across the island the next couple of days. ATLANTIC OCEAN... Outside the influence of Tropical Storm Gert and the tropical waves moving across the tropical Atlc waters...the forecast area is under the influence of the subtropical high. This high pressure area is beginning to build westward into the SW North Atlc waters along 24N in the wake of Gert as the system moves northward. Moderate to fresh winds prevail across the eastern waters between the two easternmost tropical waves and the subtropical high...with gentle to moderate winds elsewhere. The area of fresh winds will spread westward along with the tropical waves the next couple of days. For additional information please visit http://www.hurricanes.gov/marine $$ HUFFMAN