000 AXNT20 KNHC 030602 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 202 AM EDT Mon Jul 3 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 0000 UTC surface analysis and satellite imagery through 0500 UTC. ...TROPICAL WAVES... A tropical wave is in the Eastern Atlantic with axis near 20W extending from 07N to 15N, moving west at 5 to 10 kt within the last 24 hours. No significant deep convection is occurring near the wave, though there are scattered showers within 120 nm of the wave axis. The wave is embedded in a moist monsoonal flow, as seen in the Total Precipitable Water imagery, and extends across the monsoon trough. Little to no surface signature of the wave is apparent from satellite imagery and limited surface observations, though the SUNY-Albany Trough Diagnostics well depict the wave at 700 mb. A tropical wave is in the central Atlantic with axis near 32W extending from 05N to 16N, moving west at about 5 kt within the last 24 hours. A broad 1011 mb surface low is embedded on the wave axis near 10N, as suggested by low-level cloud motions. The wave also is quite apparent at 700 mb in the Trough Diagnostics. Quite dry conditions are occurring north of about 12N in the vicinity of the wave, as seen in the Saharan Air Layer imagery from Meteosat 9. Scattered moderate and isolated strong convection is occurring from 05N and 10N between 26W and 32W, while scattered showers are seen within 120 nm of the wave axis south of 12N. A tropical wave is in the Eastern Caribbean with axis near 68W extending 08N to 18N. The wave is not apparent in either the surface observations, nor in the Trough Diagnostics. However, it remains detectable in the Total Precipitable Water imagery as a maximum east of the wave axis. No significant convection or shower activity are currently noted with this wave. ...ITCZ/MONSOON TROUGH... The Monsoon Trough axis extends from the west coast of Africa near 13N17W to 08N40W. The Intertropical Convergence Zone extends from 08N40W to 08N59W along northeastern South America. Convection observed near the Monsoon Trough and ITCZ is mainly related to tropical waves. Refer to the section above for details. Otherwise, scattered moderate convection is observed from 05N to 10N between 18W and the West African coast. ...DISCUSSION... GULF OF MEXICO... A 1020 mb surface high is over the northeastern Gulf near 28N86W. A weak surface trough exists in the southwestern Gulf from 24N94W to 18N95W. Scattered moderate convection is observed within 120 nm of the trough axis south of 20N. Isolated moderate convection is occurring in the eastern Gulf within 120 nm of the southwest Florida coast. Winds throughout the Gulf are fairly tranquil, generally 5 to 15 kt. The piece of Saharan Air Layer that had moved across the Gulf during the last couple of days and reached Texas, Louisiana, and Mississippi appears to still be in place. This should gradually moisten up, though the overall synoptic pattern should not change during the next two days. CARIBBEAN SEA... The moderate pressure gradient across the Caribbean between the Bermuda high to the north and the Colombia low to the south is generally producing 10 to 20 kt tradewind easterlies. The exception is the 25 kt east to northeasterlies just north of Colombia. Scattered moderate and isolated strong convection is located in the southwesternmost Caribbean, south of 11N, associated with the eastern extension of the Northeast Pacific's monsoon trough. An upper low is centered over central Cuba, as seen in both the water vapor imagery as well as the rawindsondes from Key West, Nassau, Grand Cayman, and Kingston. It is helping to promote isolated moderate convection over the northwestern Caribbean including Cuba and the central and southeastern Bahamas. As the tropical wave along 68W this evening is relatively weak, this will have little impact on the winds/convection. The upper low should drift slowly westward during the next couple of days, enhancing scattered moderate convection from Cuba to the Yucatan of Mexico. ...HISPANIOLA... During late afternoon and early evening, scattered moderate convection occurred over central Haiti and Dominican Republic. This has since dissipated. With some increased moisture from a weak tropical wave over the eastern Caribbean, more moderate convection and showers may occur during the next couple of days. ATLANTIC OCEAN... Two tropical waves are analyzed over the basin. Refer to the Tropical Waves section above for details. The only other area with significant convection is the scattered moderate convection occurring over the central Bahamas in association with a vigorous upper-level low over Cuba. This will likely diminish during the next day as the upper-level low pushes slowly westward. A large surface trough over the central Atlantic is analyzed from near 29N48W to 12N54W moving steadily westward at 10 to 15 kt. It is possible that this trough is associated with an undiagnosed tropical wave. The trough has scattered showers occurring within 180 nm of the axis south of 20N. The remainder of the basin remains under the influence of a broad Bermuda/Azores high along 35N. This synoptic pattern will change little through Tuesday. For additional information please visit http://www.hurricanes.gov/marine $$ Landsea