000 AXNT20 KNHC 191659 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1259 PM EDT Sat Aug 19 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 1615 UTC. ...SPECIAL FEATURES... Tropical Storm Harvey is centered near 13.9N 68.1W at 19/1500 UTC or about 110 nm NNE of Curacao and about 880 nm E of Cabo Gracias a Dios on the Nicaragua and Honduras border moving W at 19 kt. Estimated minimum central pressure is 1007 mb. Maximum sustained wind speed is 35 kt with gusts to 45 kt. Scattered moderate and isolated strong convection is from 12N-17N between 65W-73W. See the latest NHC Forecast/Advisory under AWIPS/WMO headers MIATCMAT4/WTNT24 KNHC for more details. ...TROPICAL WAVES... A tropical wave extends from 10N43W to 20N38W moving W at 15-20 kt. The wave coincides with 700 mb troughing between 37W-50W...and a maximum in 850 mb relative vorticity in the vicinity of the northern extent of the wave axis. Isolated moderate convection is from 08N-12N between 37W-43W...and from 15N-22N between 37W-45W. A tropical wave extends from 16N60W to 23N57W moving W-NW at 10-15 kt. The wave coincides with broad 700 mb troughing N of 17N between 54W-64W. Latest scatterometer data indicates the wave lacks a low at the surface...however 850 mb relative vorticity is maximized along the wave axis near 21N58W. Scattered moderate convection is from 18N-22N between 55W-61W. A tropical wave extends from 10N81W to 21N81W moving W at 10-15 kt. Broad troughing at 700 mb is noted in global model data over the NW Caribbean Sea and eastern Gulf of Mexico while an upper level low is centered to the N near 24N85W. Energy from the wave has fractured to the N-NE and is analyzed as a surface trough across the Bahamas from 23N79W to 28N76W. Widely scattered moderate convection is from 10N-17N between 80W-85W. ...ITCZ/MONSOON TROUGH... The monsoon trough extends from the African coast near 10N14W to 08N21W to 10N29W. The Intertropical Convergence Zone axis extends from 10N44W to 10N56W. Scattered moderate convection is from 06N-09N between 13W-24W...and from 08N-13N between 45W-54W. ...DISCUSSION... GULF OF MEXICO... An upper level low is centered over the SE Gulf near 24N85W and continue to provide support for a surface trough analyzed across the eastern Florida panhandle near 30N83W SW to 27N86W. Low-level moisture convergence along with divergence aloft is generating scattered showers and tstms generally N of 24N between 83W-90W. Farther west...a surface ridge anchored by a 1017 mb high centered near 27N91W extends an axis S-SW across the western Gulf to 20N97W. Mostly clear skies prevail W of 90W within light to gentle anticyclonic winds. The ridge is forecast to shift N through Sunday with overall light to moderate E-SE winds expected through early next week. CARIBBEAN SEA... The primary area of concern across the Caribbean this afternoon is Tropical Storm Harvey currently tracking through the central waters. Harvey is forecast to reach Central America by Monday morning. Up until then...a tropical wave along 81W will increase cloudiness and convective precipitation across portions of Central America as the wave moves westward and into the East Pacific waters. ...HISPANIOLA... Daytime heating...local sea breezes...and mountain upslope lifting will combine with available moisture and produce scattered showers and thunderstorms across the island mainly during the afternoon and evening hours through the weekend. ATLANTIC OCEAN... The SW North Atlc remains under the influence of an upper level low centered over the SE Gulf of Mexico near 24N85W and the associated surface trough extending from central Cuba near 23N79W to 28N76W. Scattered showers and tstms are occurring from 23N-29N between 74W-79W. Otherwise...the remainder of the SW North Atlc remains fairly tranquil with influence from a surface ridge extending from 30N50W to 27N72W. Elsewhere...outside of tropical wave mentioned above...surface ridging prevails across the central and eastern Atlc anchored by a 1025 mb high centered near 35N34W and a 1024 mb high centered near 32N40W. For additional information please visit http://www.hurricanes.gov/marine $$ HUFFMAN