000 AXNT20 KNHC 190541 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 141 AM EDT Wed Jul 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 0000 UTC surface analysis and satellite imagery through 0515 UTC. ...SPECIAL FEATURES... Remnants of Don is centered near 11.9N 62.5W or about 48 nm WSW of Grenada, at 19/0300 UTC, moving westward at 22 kt. Estimated minimum central pressure is 1012 mb with maximum sustained winds of 35 kt with gusts to 45 kt. Scattered moderate to isolated strong convection is over the Windward Islands from 11N-13N between 61W- 64W. Isolated moderate convection is elsewhere near Trinidad from 09N-11N between 60W-62W. The remnants of Don will move across the southeastern Caribbean Sea tonight and Wednesday. Don is expected to produce total rain accumulations of 3 to 6 inches. There remains a potential for life-threatening flash floods and mudslides, especially in mountainous areas. Please refer to the last NHC forecast/advisory under AWIPS/WMO headers MIATCPAT5/WTNT35 KNHC for more details. ...TROPICAL WAVES... A tropical wave is introduced off the coast of W Africa with axis from 15N17W to 07N19W moving W at 20kt. SSMI imagery shows a moist area from 04N-15N between 13W-23W. There is also a well defined 700 mb trough associated with the wave. Scattered moderate to isolated strong convection is mostly W of the wave axis from 08N-12N between 18W-24W. A tropical wave with an embedded low pressure is in the central Atlc. Its axis extends from 16N40W to a 1012 mb low near 10N41W to 04N41W, moving W at 5-10 kt. The SSMI total precipitable water imagery shows a very large moist area over from 04N- 23N between 30W-45W. The embedded surface low is well defined. Scattered moderate to isolated strong convection is from 09N-14N between 40W-45W. Some slow development of this system is possible during the next day or two while it moves toward the west-northwest. Potential for tropical cyclone development from this system remains low through the next two days. A tropical wave is in the E Caribbean with axis extending from 19N67W to inland Venezuela near 10N68W, moving W at 20 kt. The wave is in a region of unfavorable wind shear, and Saharan dry air and dust are affecting the western periphery of the wave environment. Isolated showers are within 90 nm of the wave axis. ...ITCZ/MONSOON TROUGH... The monsoon trough axis extends from 12N16W to 09N24W to 11N41W to 10N50W. The ITCZ then extends from 10N50W to 09N58W. Aside from the convection associated with the tropical waves, widely scattered moderate convection is from 07N-12N between 45W-48W. ...DISCUSSION... GULF OF MEXICO... A surface trough is over the Yucatan Peninsula from 21N90W to 16N92W. Scattered showers are within 60 nm of the trough axis. Further W, scattered moderate to isolated strong convection is over the W Bay of Campeche and S Mexico from 16N-20N between 94W- 99W. The remainder of the Gulf of Mexico has weak surface ridging 5-10 kt southerly flow. Radar imagery shows scattered showers over the Straits of Florida. In the upper levels, an upper level low is centered over Mexico near 23N98W. Upper level diffluence SE of the center is enhancing convection over S Mexico. Expect in 24 hours for a 1019 mb high to form over the NE Gulf near 28N87W. Also expect scattered showers and thunderstorms to form over Florida, and the Bay of Campeche, during maximum heating Wednesday. CARIBBEAN SEA... The main feature of concern for the SE Caribbean is the remnants of Don moving across the Windward Islands, and a tropical wave along 67W. Scattered moderate to strong convection is inland over SE Venezuela, and over N Colombia. Widely scattered moderate convection is over the SW Caribbean S of 11N. Elsewhere, scattered showers and isolated thunderstorms are over the NW Caribbean from 16N-21N between 79W-85W. Of note in the upper levels, an upper level low is centered over E Cuba near 19N75W. Expect additional convection over the S Caribbean and Central America over the next 24 hours. ...HISPANIOLA... A fast moving tropical wave is supporting isolated showers across the Dominican Republic and adjacent waters, including the Mona Passage. The wave will traverse the island tonight and Wednesday. Expect scattered thunderstorms over the island during maximum heating Wednesday. ATLANTIC OCEAN... Scattered showers are over the N Bahamas and the W Atlantic, N of 25N and W of 73W. A large 1030 mb high is centered over the central Atlantic near 34N43W producing fair weather. As typical for this time of year, tropical waves are moving through the tropical Atlantic waters. Of note in the upper levels, an upper level high is over the W Atlantic near 33N66W producing upper level diffluence over Florida. An upper level low is also centered over the W Atlantic near 25N49W enhancing showers NW of center. For additional information please visit http://www.hurricanes.gov/marine $$ Formosa