000 AXNT20 KNHC 280600 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 200 AM EDT THU JUL 28 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 east Atlantic east of the Cape Verde Islands. The wave extends from 07N-15N with axis near 20W, moving W at 5 kt within the last 12 hours. The wave is being engulfed by Saharan dry air and dust, which have significantly reduced the convection associated with it. The CIRA LPW imagery show dry air from the surface to 850 mb in the northern wave environment, which is devoid of convection. Scattered showers are in the southern portion of the wave from 07N-13N E of 22W. Some development of this system is possible during the next few days while it moves W or W-NW. However, environmental conditions are expected to become less conducive for development early next week while the system is over the central tropical Atlantic Ocean. A tropical wave is in the central Atlantic W of the Cape Verde Islands extending from 10N-18N with axis near 33W, moving at 15 kt within the last 24 hours. Meteosat composite imagery show Saharan dry air and dust in the wave environment. CIRA LPW imagery from the surface to 850 mb confirms dry air intrusion in the wave environment, which is keeping the wave devoid of convection. A tropical wave is in the central Atlantic from 09N-18N with axis near 46W, moving west at 15 kt within the last 24 hours. CIRA LPW imagery show mainly dry air from the surface to 850 mb associated with this wave. The dry air is due to the presence of abundant Saharan dry air and dust, which continue to hinder convection at the time. A tropical wave is in the west Caribbean from 11N-22N with axis near 79W, moving west at 25 kt within the last 24 hours. Aloft, water vapor imagery show strong dry subsidence across most of the SW Caribbean, which is inhibiting convection in that region of the wave. However, shallow moisture in the NW Caribbean and divergent flow aloft support isolated showers and tstms N of 17N W of 74W. ...ITCZ/MONSOON TROUGH... The Monsoon Trough extends across Africa into the east Tropical Atlantic near 19N16W and continues to 11N30W to 08N46W where the ITCZ begins and continues to Guyana near 08N59W. Aside from the convection related to the tropical waves, scattered heavy showers are from 03N-11N between 26W and 38W. ...DISCUSSION... GULF OF MEXICO... A broad inverted upper-level trough covers most of the Gulf of Mexico. This feature along with shallow moisture across the basin support isolated showers and tstms N of 21N. A surface trough is off the W Yucatan Peninsula supporting scattered heavy showers and tstms S of 21N E of 93W. Otherwise, weak surface ridging is elsewhere being anchored by a 1018 mb high in the NE basin near 28N85W. Scatterometer data depicts gentle to moderate return flow across most of the Gulf. Weak surface pressure and return flow will prevail the next two days. CARIBBEAN SEA... A tropical wave is in the west Caribbean from 11N-22N with axis near 79W. Aloft, water vapor imagery show strong dry subsidence across most of the SW Caribbean, which is inhibiting convection in that region of the wave. However, shallow moisture in the NW Caribbean and divergent flow aloft support isolated showers and tstms N of 17N W of 74W. In the SW basin, the monsoon trough supports heavy showers and tstms S of 10N E of 78W. Water vapor and CIRA LPW imagery show dry stable air across the remainder basin, which is supporting fair weather. Fresh to strong winds continue across the central Caribbean between 67W and 79W, which are expected to amplify west and continue through the weekend. The next tropical wave will enter the east Caribbean by late Friday. ...HISPANIOLA... Hispaniola enjoys fair weather tonight as stable deep layer dry air moves across the Island. Haze and dust are being reported in the N and SE portions Dominican Republic due to the presence of Saharan air in the region as indicated by Meteosat composite imagery. Except for afternoon showers to be concentrated over the central and western portions of the Island, fair weather is expected through Friday. ATLANTIC OCEAN... Three tropical waves are moving across the basin. Please refer to the tropical waves section for more details. Surface high pressure is across the remainder basin being anchored by a 1033 mb high centered N of the Azores Islands. Little change is expected through the next 48 hours. For additional information please visit http://www.hurricanes.gov/marine $$ RAMOS