000 AXNT20 KNHC 070007 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 807 PM EDT Thu Jul 6 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 2315 UTC. ...SPECIAL FEATURES... Tropical Depression Four is centered near 13.1N 44.9W at 06/2100 UTC or about 965 nm east of the Lesser Antilles moving WNW at 20 kt. Estimated minimum central pressure is 1009 mb. Maximum sustained wind speed is 25 kt with gusts to 35 kt. Widely scattered moderate convection is located within 120 nm of the western semicircle. The depression is expected to degenerate to a remnant low by Friday night, but it could also open up into a tropical wave at any time. Please see the latest NHC Public Advisory under AWIPS/WMO headers MIATCPAT4/WTNT34 KNHC and the full Forecast/Advisory under the AWIPS/WMO headers MIATCMAT4/WTNT24 KNHC for more details. ...TROPICAL WAVES... A tropical wave is just off the W coast of Africa with axis extending from 15N19W to 04N20W, moving W at 5-10 kt during the past 24 hours. The wave is in a region of favorable to neutral wind shear. However, extensive intrusion of Saharan dry air and dust to the wave environment hinder convection at the moment N of 08N. Scattered moderate convection is from 05N to 09N between 17W and 25W. A tropical wave is over the E Caribbean with axis extending from 20N60W to 08N61W, moving W at 15 kt during the past 24 hours. The wave is in a region of favorable to neutral wind shear. However, intrusion of Saharan dry air and dust to the wave environment hinder deep convection at the time. Shallow moisture and upper level diffluence support isolated showers from 09N to 15N between 56W and 62W. A tropical wave located over the W Caribbean with axis extending from 22N82W to 11N84W, moving W at 20 kt during the past 24 hours. The wave is in a region of unfavorable wind shear. However, shallow moisture and upper level diffluent flow between a low over the SE Gulf of Mexico and a broad ridge covering the W Caribbean support scattered moderate convection within 120 nm of the wave axis. A tropical wave is moving over the SW Gulf of Mexico with axis extending from 26N95W to 15N95W, moving W at 15-20 kt during the past 24 hours. The wave is in a region of favorable to neutral wind shear. Shallow moisture and upper level diffluent flow between a low over central Mexico and a broad ridge anchored in the EPAC waters support scattered moderate convection within 120 nm of the wave axis. ...ITCZ/MONSOON TROUGH... The Monsoon Trough extends from 13N17W to 07N20W to 04N29W. The Intertropical Convergence Zone extends from 04N29W to 03N40W to 08N47W to 11N58W. Aside from the convection related to the tropical wave off the coast of Africa, widely scattered moderate convection is within 90 nm of the axis between 35W-50W. ...DISCUSSION... GULF OF MEXICO... A tropical wave is over the SW Gulf of Mexico producing scattered moderate convection. See above. A 1022 mb high is centered over the NE Gulf near 29N95W with 5 kt anticyclonic winds. Radar imagery shows scattered moderate convection over W Cuba and the Straits of Florida from 22N-24N between 80W-84W. Similar convection is S of Tampa Florida from 26N-28N between 82W-83W. In the upper levels, a small upper level low is centered over Mexico near 22N100W. Another small upper level low is centered over the SE Gulf near 25N84W. Expect convection to continue over the SW Gulf over the next 24 hours. CARIBBEAN SEA... A tropical wave is moving across the W Caribbean, while another tropical wave is over the E Caribbean. See above. Scattered moderate convection is over the higher elevations of Cuba. Scattered moderate to isolated strong convection is over the SW Caribbean and Panama from 07N-11N between 78W-82W. 10-25 kt tradewinds are elsewhere over the Caribbean with strongest winds along the coast of N Colombia. In the upper levels, a small upper level high is centered over the NW Caribbean near 17N87W. Expect the tropical waves to move W over the next 24 hours with convection. Also expect convection to continue over the SW Caribbean over the next 24 hours. ...HISPANIOLA... Presently scattered moderate convection is over the higher elevations of Haiti. Expect Hispaniola to have a decrease in convetion over the next 24 hours as the island in between tropical waves. ATLANTIC OCEAN... Tropical Depression Four and a tropical wave are analyzed over the tropical Atlantic. See above. A surface trough is over the N Bahamas with scattered showers. A broad 1029 mb surface high is centered north of our area near 36N35W producing fair weather. This synoptic pattern will change little through the next couple of days. For additional information please visit http://www.hurricanes.gov/marine $$ Formosa