912 AXNT20 KNHC 280522 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 122 AM EDT Sat Jul 28 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 0000 UTC surface analysis and satellite imagery through 0515 UTC. ...TROPICAL WAVES... A tropical wave is off the coast of W Africa with axis extending from 07N-20N along 19W, moving westward at 15 kt. A 700 mb trough is noted along the wave axis. Intrusion of Saharan dry air and dust is hindering convection N of 14N. Scattered showers are within 90 nm of the axis S of 14N. A tropical wave extends over the east Atlantic with axis from 05N-17N along 36W, moving westward at 15 kt. The wave is engulfed in a dry and dusty Saharan airmass, that is suppressing convection mainly north of 10N. Shallow moisture associated with the monsoon trough and diffluence in the upper-levels support scattered moderate convection from 06N-09N between 35W-39W. A tropical wave is over the central Atlantic with axis extending from 04N-18N along 46W, moving westward at 15 kt. Intrusion of Saharan dry air and dust to the wave's environment is hindering convection N of 10N. Scattered moderate convection is from 06N-09N between 41W-46W. A tropical wave is over the E Caribbean with axis extending from 06N-19N along 61W, 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 showers are 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 81W, moving westward at 10 kt. Scattered moderate to isolated strong convection is over Cuba from 20N-23N between 77W-84W. Widely scattered moderate convection is over the southern portion of the wave from 09N-12N between 76W-82W. ...MONSOON TROUGH/ITCZ... The monsoon trough extends from the coast of Africa near 20N16W to 10N24W to 09N36W to 08N42W. The ITCZ extends from 08N42W to 07N45W. The ITCZ resumes W of a tropical wave near 07N47W and continues to the coast of South America near 05N53W. Besides the convection mentioned in the tropical wave section, scattered moderate convection is from 8N-10N between 28W-33W. ...DISCUSSION... GULF OF MEXICO... A small 1018 mb high is centered over the E Gulf of Mexico near 27N85W with 5-10 kt anticyclonic winds. A staionary front is just N of the Florida Panhandle. Scattered showers remain over Florida 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 showers 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 76W-82W. This activity is also related to a tropical wave, currently extending along 81W. Isolated showers are occurring over the Virgin Islands, Puerto Rico, and Hispaniola due to an upper-level low centered north of Hispaniola near 21N71W. A tropical wave is over the E Caribbean along 61W. Another tropical 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 showers north of 20N W of 73W. The Atlantic subtropical ridge dominates the remainder of the basin being anchored by a 1030 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