906 AXNT20 KNHC 280005 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 805 PM EDT Fri Jul 27 2018 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. ...TROPICAL WAVES... A tropical wave extends across the east Atlantic with axis from 05N-17N along 34W, moving W at 10-15 kt. The wave is being covered by a Saharan air, which is suppressing convection mainly north of 10N. Shallow moisture associated with the monsoon trough and diffluence in the upper-levels support scattered showers along the wave's axis south of 10N. A tropical wave is over central Atlantic with axis extending from 05N-17N along 44W, moving westward at about 10 kt. Intrusion of Saharan dry air and dust to the wave's environment is hindering convection at this time. A tropical wave is over the central Atlantic with axis extending from 06N-19N along 59W, moving westward at about 10 kt. Intrusion of Saharan dry air and dust to the wave's environment is hindering convection N of 12N. Scattered moderate convection is W of the wave axis from 06N-11N between 59W-64W. A tropical wave is over the west-central Caribbean with axis south of 21N along 79W, moving W at 10 kt. Scattered moderate to isolated strong convection is over Cuba. Similar convection is over the southern portion of the wave from 09N-15N between 76W- 81W. ...MONSOON TROUGH/ITCZ... The monsoon trough extends from the coast of Africa near 19N16W to 11N22W to 08N30W to 09N40W. The ITCZ extends from 09N40W to 08N43W. The ITCZ resumes W of a tropical wave near 07N46W and continues to the coast of South America near 05N53W. Scattered moderate convection is from 0-8N-11N between 26W-28W. Isolated moderate convection is from 07N- 10N between 35W-42W. ...DISCUSSION... GULF OF MEXICO... A small 1018 mb high is centered over the SE Gulf of Mexico near 26N85W with 5-10 kt anticyclonic winds. A staionary front is just N of the Florida Panhandle. Scattered moderate convection is over most of Florida, Cuba, and N Yucatan Peninsula. Mostly fair weather is over the W Gulf. Surface ridging will prevail again across the basin over the weekend. Scattered showers are likely over the Bay of Campeche associated with a tropical wave that will move into this region by Sunday. CARIBBEAN SEA... Shallow moisture in the northwest Caribbean with a divergent environment aloft are supporting scattered moderate to isolated strong convection over the NW Caribbean from 19N-22N between 80W-86W. In the southwest Caribbean, the EPAC's monsoon trough supports scattered showers south of 12N between 78W-83W. This activity is also related to a tropical wave, currently extending along 79W. Refer to the section above for more details. Isolated showers are occurring in the northern Leeward Islands and the Virgin Islands being supported by diffluence aloft associated to an upper-level low centered northeast of Puerto Rico. A new tropical wave is forecast to move across the Lesser Antilles tonight, and a second wave will enter the east Caribbean by Sun night. Otherwise, fresh to strong winds are forecast for the south-central basin through the weekend. ATLANTIC OCEAN... Three tropical waves are moving across the basin. Please refer to the section above for more details. Diffluent flow between the base of an upper-level trough over the southeast CONUS and a high over the northern Bahamas continue to support scattered moderate convection north of 20N W of 73W. Farther east, a middle level low just north of Hispaniola supports a surface trough that extends from 25N66W to 22N68W. Scattered moderate convection is noted with this features between 64W-70W. The Atlantic subtropical ridge dominates the remainder of the basin being anchored by a 1029 mb high centered near 37N53W. Surface ridging will dominate the central and eastern Atlantic through the weekend providing stable and dry conditions. For additional information please visit http://www.hurricanes.gov/marine $$ Formosa