000 AXNT20 KNHC 040005 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 805 PM EDT Thu Aug 3 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 1800 UTC surface analysis and satellite imagery through 2345 UTC. ...SPECIAL FEATURES... A tropical wave is in the E Atlc with axis extending from 18N29W to 08N26W, moving W at 5-10 kt within the last 24 hours. The wave is in a region of low to moderate vertical wind shear, and some Saharan dry air and dust continue to enter the wave environment. A broad cyclonic circulation is observed in the southern wave environment where the monsoon moisture support scattered moderate convection and isolated tstms from 06N to 11N between 26W and 34W. The latest scatterometer pass showed a center of low pressure of 1010 mb E of this wave near 10N21W, which is supporting isolated showers from 06N to 12N E of 26W. There is a medium chance for this system to become a tropical cyclone within the next two days. ...TROPICAL WAVES... A tropical wave is in the central Atlc with axis extending from 18N38W to 09N45W, moving W at 10-15 kt within the last 24 hours. The wave is in a region of mainly low to moderate vertical wind shear. However, it continues to be severely affected by Saharan dry air and dust, which is suppressing convection at the time. A tropical wave is in the E Caribbean associated with a 1012 mb low near 12N65W. The wave axis extends from 19N67W to the low, and it has been moving W at 15 kt within the last 24 hours. CIRA LPW show abundant low level moisture in the wave environment that along with diffluent flow aloft support scattered showers and isolated tstms from 10N to 18N between 60W and 70W. ...ITCZ/MONSOON TROUGH... The monsoon trough extends from the African coast near 14N17W to 07N30W to 11N42W. The Intertropical Convergence Zone axis extends from 10N47W to 12N60W. For convection information, see the tropical waves section. ...DISCUSSION... GULF OF MEXICO... A middle to upper level trough is noted on water vapor imagery over the eastern half of the United States with axis extending from Minnesota to Louisiana adjacent waters. The troughing supports a surface trough extending from the Florida panhandle near 30N86W to the Texas coast near 26N97W. To the south of the trough aloft, the eastern periphery of a broad ridge anchored over NW Mexico generates divergent flow aloft that is supporting numerous heavy showers off the coast of Texas from 25N to 28N and scattered heavy showers with tstms elsewhere N of 26N. Fresh to strong with occasional gusty winds are expected in these areas of convection. The boundary is expected to drift northward tonight, leaving the basin with light to gentle anticyclonic winds Friday. Elsewhere, a surface ridge extends across the southern Florida peninsula to the central Gulf. Mostly clear skies and fair conditions are expected to persist with the ridge remaining in place across the basin through Wednesday of next week. CARIBBEAN SEA... A tropical wave is moving across the eastern Caribbean generating a broad area of scattered showers and tstms generally E of 70W. Abundant low level moisture and upper level diffluent flow support scattered showers and tstms over central Haiti and Hispaniola adjacent waters to 15N. Father west, a surface trough with axis from 18N78W to 10N81W support scattered showers and tstms W of 76W. Fresh to strong winds are expected to accompany the tropical wave with continued strong convection through Sunday as it moves towards the W Caribbean. ...HISPANIOLA... Abundant low level moisture and upper level diffluent flow support scattered showers and tstms over central Haiti and Hispaniola adjacent waters to 15N. A tropical wave is expected to pass S of the island tonight into early Friday and then across the remainder of the central Caribbean on Friday. Continued scattered showers and tstms are expected through Friday across the region with any lingering activity moving into the western Caribbean during the upcoming weekend. ATLANTIC OCEAN... Scattered heavy showers and tstms are off the NE Florida coast associated with a surface trough moving across the Florida Peninsula. Otherwise...the remainder of the central and eastern Atlc are under the influence of a surface ridge anchored by a pair of 1026 mb highs...one centered S of the Azores near 33N27W and the other centered near 29N53W. For additional information please visit http://www.hurricanes.gov/marine $$ Ramos