249 AXNT20 KNHC 241706 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 106 PM EDT Fri Aug 24 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 1200 UTC surface analysis and satellite imagery through 1715 UTC. ...TROPICAL WAVES... A tropical wave is off the coast of W Africa along 18W from 04N- 20N, moving westward at 15 kt. The wave is in a moist environment and has 700 mb support. Scattered showers are from 11N-21N between 16W-26W. A central Atlantic tropical wave has its axis along 42W from 02N- 17N, moving westward at 15 kt. The wave is embedded within a very dry and stable environment which is inhibiting significant convection at this time. Scattered showers are noted where the wave meets the monsoon trough along and south of 10N. An E Caribbean tropical wave has its axis along 63W from 02N- 20N, moving westward at 10-15 kt. This wave is also embedded within a very dry and stable environment caused by Saharan Air Layer that is spreading westward. Scattered moderate convection is near Trinidad from 09N-11N between 60W-64W. A W Caribbean tropical wave has its axis along 82W south of 20N to 03N81W. The wave is moving westward at 15-20 kt. Scattered moderate to strong convection is over the southern portion of the wave from 08N-13N between 75W-84W. A tropical wave has its axis along 96W south of 20N, moving westward near 10-15 kt. Scattered showers are over the Bay of Campeche S of 20N. ...MONSOON TROUGH/ITCZ... The monsoon trough extends from the African coast near 14N16W to 08N26W to 09N39W. The ITCZ begins W of a tropical wave from 07N43W to 04N51W. A 1012 mb low is centered on the monsoon trough near 09N39W. Scattered moderate convection is within 90 nm of the low center. Isolated moderate convection is along the monsoon trough from 03N-06N between 10W-40W. Scattered showers are along the ITCZ from 02N-06N between 40W-48W. ...DISCUSSION... GULF OF MEXICO... A weakening stationary front extends across N Florida from 30N80W to 28N83W. Scattered showers are over the Florida Peninsula. An approaching tropical wave is advecting scattered showers oveer W Cuba and the Straits of Florida. The Bay of Campeche has similar showers due to another tropical wave. The remainder of the Gulf has fair weather. The pressure gradient across the Gulf supports light winds throughout, with a wind shift along the frontal system. In the upper levels, an upper level high centered over southern Texas near 30N98W is producing NE upper level winds over the Gulf with upper level moisture. Expect the front to fully dissipate during the next six hours. CARIBBEAN SEA... Two tropical waves are moving across the basin. Refer to the section above for details. An upper-level low is centered near the Gulf of Honduras at 17N85W. The low is enhancing scattered showers near the upper-low center, and is enhancing convection over the SW Caribbean with upper level diffluence. Expect strong nocturnal pulses of wind through the upcoming weekend along the coast of Colombia and Venezuela with seas building to 9 ft. A new tropical wave will reach 55W on Sun. ATLANTIC OCEAN... Two tropical waves are moving across the basin. Refer to the section above for details. A stationary front is off the coast of northern Florida from 32N76W to 30N80W. Scattered moderate convection is north of 26N and west of 70W. An upper level low is centeredE of the Bahamas near 24N71W enhancing convection. A surface trough extends over the central Atlantic from 31N38W to 24N40W. Scattered showers are noted within 90 nm of the trough. Saharan dust and associated dry air is noted mainly east of 60W on GOES-16 GEO color dust imagery. The dust is suppressing convection across most of the tropical Atlantic waters from 15N- 30N. For additional information please visit http://www.hurricanes.gov/marine $$ Formosa