000 AXNT20 KNHC 251024 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 624 AM EDT MON JUL 25 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 0600 UTC surface analysis and satellite imagery through 1015 UTC. ...TROPICAL WAVES... A tropical wave is in the eastern Atlantic from 09N-19N with axis near 29W, moving W at 10 kt within the last 24 hours. The wave is associated with a 1011 mb low centered near 13N29W. Meteosat composite imagery show Saharan dry air and dust intrusion into the wave environment, which is hindering convection at the time. A tropical wave is in the west Atlantic from 08N-21N with axis near 56W, moving at 30 kt within the last 24 hours. CIRA LPW from the surface to 850 mb show moisture has increased in the northern wave environment, which is supporting scattered moderate convection from 17N-20N between 56W and 59W. Meteosat composite imagery show Saharan dry air and dust in the remainder wave environment, which hinder the convection elsewhere. A tropical wave is in the Bay of Campeche S of 21N with axis near 95W, moving west at 20 kt within the last 24 hours. A cluster of heavy showers and scattered tstms is in the Bay of Campeche S of 21N between 92W and 96W. ...ITCZ/MONSOON TROUGH... The Monsoon Trough extends across Africa into the east Tropical Atlantic near 14N17W and then continues along 14N25W to a 1011 mb low near 13N29W to 08N34W to 08N46W. The ITCZ begins near 08N46W and continues west to the coast of Guyana near 07N58W. Aside from the convection associated with the waves, scattered moderate convection is from 07N-12N E of 23W, from 05N-08N between 24W and 38W and from 06N-10N W of 50W. ...DISCUSSION... GULF OF MEXICO... Weak surface ridging continue to cover most of the basin N of 21N and provides gentle to moderate return flow. South of 21N, in the Bay of Campeche, a tropical wave is generating heavy showers and scattered tstms S of 19N between 92W and 96W. The latest scatterometer pass show fresh to strong NE winds within 120 nm off the western Yucatan Peninsula. For further information about the wave refer to the tropical waves section above. In the middle levels, a broad low centered cover the SE Gulf while an inverted trough moves across SW Gulf waters. Divergent flow aloft between these two features along with abundant moisture in the basin support scattered moderate convection from 22N-28N E of 90W. Isolated showers are elsewhere N of 22N between 90W and 94W. Expect showers to continue in the Bay of Campeche today. A surface trough will develop and prevail in the SW Gulf the next two days with high pressure dominating elsewhere. CARIBBEAN SEA... A broad inverted trough in the upper levels along with shallow moisture in the NW Caribbean support isolated showers and tstms N of 15N W of 76W while farther east a surface trough support similar precipitation activity in the Windward Passage. Isolated showers are also possible for inland Hispaniola, the Mona Passage and Puerto Rico. Scattered showers and tstms are within 90 nm off Colombia and Panama associated with a 1009 mb low pressure near 09N76W. The gradient between this low and higher pressure in the Atlc extending to the northern Caribbean support fresh to strong winds S of 14N between 68W and 75W. This area of winds will prevail the next two days, increasing in areal coverage before Tuesday sunrise. Strong dry air subsidence from aloft support fair weather elsewhere. A tropical wave will enter the eastern Caribbean tonight. ...HISPANIOLA... A surface trough and associated broad surge of moisture support isolated showers and tstms in the Windward Passage and isolated showers inland Hispaniola as well as the Mona Passage. Moisture associated with this trough will continue to enhance showers across the Island today through early morning Tuesday. ATLANTIC OCEAN... Two tropical waves are moving across the Atlantic waters with no significant convection. Please refer to the tropical waves section above for details. Isolated showers are in the northern Bahamas associated with a zone of diffluent flow aloft. Similar convection is in the Turks and Caicos Islands associated with a surface trough that is moving across Hispaniola today. Otherwise, surface ridging and fair weather dominate elsewhere. No major changes expected in the next two days. For additional information please visit http://www.hurricanes.gov/marine $$ RAMOS