142 AXNT20 KNHC 240517 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 117 AM 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 0000 UTC surface analysis and satellite imagery through 0515 UTC. ...TROPICAL WAVES... A central Atlantic tropical wave has its axis along 37W from 02N- 20N, 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. A central Atlantic tropical wave has its axis extending along 57W 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 across the Atlantic. A few showers are developing along 10N. A west Caribbean tropical wave has its axis along 79W south of 20N to 03N79W. The wave is moving westward at 15-20 kt. Scattered moderate convection is observed with the portion of the wave south of 12N, and over the northern portion of the wave affecting Cuba, Jamaica and adjacent waters. A tropical wave has its axis along 91W south of 20N, moving westward near 10-15 kt. Scattered moderate convection is over the portion of the wave located over the Yucatan Peninsula. Scattered showers are noted along 08N due to the monsoon trough's interaction with the wave. ...MONSOON TROUGH/ITCZ... The monsoon trough extends from the African coast near 14N17W to 10N45W. The ITCZ begins from that point to 07N55W. Scattered moderate convection is observed east of 20W. ...DISCUSSION... GULF OF MEXICO... A weakening stationary front extends across the northern gulf waters along 28N. A pre-frontal trough extends from central Florida near 27N82W to 25N89W. Scattered moderate convection prevails along the trough. To the southwest, a tropical wave is enhancing convection across the Yucatan Peninsula. Refer to the section above for details. 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 is producing NE upper level winds over the Gulf with upper level moisture. Expect the front to dissipate during the next 24 hours. CARIBBEAN SEA... A tropical wave is moving across the basin. Refer to the section above for details. An upper-level low is centered near the Cayman Islands at 19N84W. The low is enhancing scattered convection near the upper-low center and the tropical wave along 79W. Scattered moderate convection is over the southwest Caribbean S of 12N affecting Panama and Costa Rica. Expect strong nocturnal pulses of wind through the upcoming weekend along the coast of Colombia and Venezuela with seas building to 9 ft. The next tropical wave will enter the eastern portion of the basin during the weekend. 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 30N81W to 32N76W. Scattered moderate convection is north of 28N and west of 76W. To the east, scattered showers are over the west Atlantic from 25N-30N between 67W-74W due to an upper-level low centered near 25N72W. A surface trough extends over the central Atlantic from 24N57W to 21N60W. Scattered showers are noted along the trough. Another trough extends from 32N34W to 26N37W. Saharan dust and associated dry air, although not as dense as in previous days, is noted mainly east of 60W on GOES-16 GEO color dust imagery. The dust is keeping convection limited to non-existent across most of the Atlantic waters. For additional information please visit http://www.hurricanes.gov/marine $$ ERA