000 AXNT20 KNHC 260600 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 200 AM EDT TUE JUL 26 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 0000 UTC surface analysis and satellite imagery through 0545 UTC. ...TROPICAL WAVES... A tropical wave is in the eastern Atlantic from 09N-19N with axis near 21W, forecast to move at 15 kt within the next 24 hours. Meteosat composite imagery show Saharan dry air and dust engulfing the northern wave environment. A surge of moderate moist air from surface to 850 mb and divergent flow in the middle to upper levels support a cluster of moderate to strong convection from 10N-12N between 18W and 23W. A tropical wave is in the central Atlantic from 08N-18N with axis near 33W, moving west at 10 kt within the last 24 hours. CIRA LPW imagery show moderate moist from the surface to 850 mb associated with this wave and global model guidance show a low at 700 mb coinciding with the wave axis location. Even with a divergent environment at the upper levels, the presence of Saharan dry air and dust seems to hinder convection at the time. A tropical wave is in the far eastern Caribbean from 10N-22N with axis near 62W, moving west at 20 kt within the last 24 hours. The wave is associated with shallow moisture, which is is supporting scattered showers and tstms across the Virgin Islands, eastern Puerto Rico and adjacent waters. Isolated showers are possible across the Lesser Antilles. ...ITCZ/MONSOON TROUGH... The Monsoon Trough begins west of a tropical wave near 12N22W and continues to 11N33W to 08N46W. The ITCZ begins near 08N46W and continues to 08N58W. Besides the convection associated with the tropical waves, scattered moderate convection is from 03N-10N between 24W and 44W. ...DISCUSSION... GULF OF MEXICO... A broad middle level low centered near 26N91W covers most of the basin and supports a 1012 mb low over SE Louisiana with an associated surface trough extending from 28N95W to the low center near 29N90W to 27N87W. Scatterometer data show S to SW moderate to fresh winds N of 26N E of the low while surface observations show moderate to fresh N to NW flow within 90 nm W of the low center. Instability generated by the middle and surface lows along with widespread moderate moisture across the basin support scattered showers N of 23N between 85W and 95W. Clusters of heavy showers and tstms are in the Yucatan Channel quickly moving W-NW to northern adjacent waters of the Yucatan Peninsula. Over the eastern Bay of Campeche, a surface trough support scattered showers S of 21N. Otherwise, weak surface ridging prevails E of 87W. Expect for the surface low and trough to dissipate within the next 24 hours. A thermal trough will move off the west coast of the Yucatan peninsula each evening through midweek. CARIBBEAN SEA... An inverted upper-level trough covers the basin W of 75W with an embedded low just S of Cuba that supports clusters of heavy showers and tstms over the southern Island coastal waters and isolated showers and tstms elsewhere in the NW Caribbean, including the Gulf of Honduras. A shortwave upper trough is across the central Caribbean where the remnants of a former surface trough support passing showers across Hispaniola and the Windward passage. In the SW basin, the monsoon trough support scattered showers and tstms within 90 nm of the coast of northern Panama and Costa Rica and isolated showers elsewhere S of 12N. A tropical wave is moving across the Lesser Antilles where it generates isolated showers. The wave also support scattered showers and tstms over the Virgin Islands and Puerto Rico. See the tropical waves section above. Scatterometer data depict fresh to strong winds in the south-central basin and moderate trades elsewhere. Showers will continue across Puerto Rico and will increase across Hispaniola Tuesday as the wave continue to move westward. ...HISPANIOLA... A shortwave upper trough is across the central Caribbean where the remnants of a former surface trough support passing showers across Hispaniola and the Windward passage. Showers will increase across Hispaniola Tuesday as a tropical wave in the eastern Caribbean continue to move westward. ATLANTIC OCEAN... Three tropical waves are moving across the basin. Please refer to the section above for details. A surface ridge extends across the remainder Atlantic waters being anchored by a 1031 mb high centered N of the Azores Islands. Expect for the surface ridge to persist through the next 24 hours. For additional information please visit http://www.hurricanes.gov/marine $$ RAMOS