000 AXNT20 KNHC 020522 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 122 AM EDT Mon Jul 2 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... The tropical wave has an axis extending from 15N27W to 04N28W and is moving W at around 15-20 kt. Scattered moderate convection is noted from 04N to 08N between 21W and 35W. A total precipitable water surge is noted within this wave. A tropical wave has an axis extending from 18N46W to 04N48W. This wave is moving W at around 15-20 kt. This wave is well defined in model 700 and 850 mb fields and coincides with an inverted-V signature in total precipitable water data. At this time, the wave is surrounded by Saharan dust which is inhibiting deep convection. A tropical wave has an axis extending from 20N65W to 05N65W, moving westward at 15-20 knots. This wave is clearly defined with an inverted-V signature evident in visible satellite imagery. Scattered moderate convection prevails across the portion of the wave over South America, while Saharan dust surrounds the northern portion of the wave inhibiting convection. Tropical moisture associated with this feature will continue to spread west over the southeast and south-central Caribbean, well ahead of the actual wave axis. A tropical wave has an axis extending from the Yucatan Peninsula into the EPAC waters near 07N91W. Infrared satellite imagery as well as total precipitable water data confirm the location of this wave. The wave will continue moving across southern Mexico tonight enhancing shower and thunderstorm activity. ...MONSOON TROUGH/ITCZ... The monsoon trough enters the Atlantic Ocean from the coast of Africa near 15N18W and extends to 11N23W. The ITCZ extends from 06N32W to 05N46W. Aside from the convection associated with the tropical waves, scattered showers are noted south of the ITCZ between 32W-38W. ...DISCUSSION... GULF OF MEXICO... A surface trough extends over the northeastern Gulf from a 1015 mb low near 31N86W to 27N86W. Abundant cloudiness and scattered showers and thunderstorms are associated with the low/trough affecting mainly the waters N of 27N and E of 89W. The low is expected to dissipate tonight, and the trough will drift northwestward. Scattered showers and thunderstorms will continue over much of the NE and north-central Gulf waters through at least Mon associated with these features. The remainder of the basin is under the influence of a weak high pressure center located over the Atlantic. This system is producing light to gentle anticyclonic flow and seas of 1-3 ft over the eastern half of the Gulf, and gentle to moderate SE to S winds and seas of 3-5 ft over the western half of the Gulf. This weak high pressure pattern will change little through mid-week. A surface trough will emerge off the Yucatan Peninsula each evening through Wed, enhancing nocturnal winds over the SW Gulf through this period. CARIBBEAN SEA... A tropical wave is moving across the eastern Caribbean and central America. Please see the Tropical Waves section for details. Scatterometer data depicted fresh to strong winds across the south-central Caribbean south of 14N between 70W and 78W, while moderate to fresh trades prevail across the remainder of the basin S of 18N and E of 82W. Light to gentle winds are noted over the NW Caribbean. A surface ridge will remain north and northeast of the Caribbean and Tropical N Atlantic waters through the next few days. Fresh to strong winds across the south-central Caribbean will gradually diminish through Tue, before strengthening again on Wed. Convection continues to flare up over the SW Caribbean mainly in the vicinity of the monsoon trough, which is just north of Panama along 09N. An upper-level low, currently just south of central Cuba, will drift westward across the NW Caribbean through today, and will enhance convection across the extreme western Caribbean waters and over land areas across the NW Caribbean. ATLANTIC OCEAN... Two tropical waves are moving across the waters between the coast of West Africa and the Lesser Antilles. Refer to the Tropical Waves section above for details. A surface trough extends from a 1014 mb low centered near 30N64W to 24N66W. Scattered showers are from 26N to 30N between 59W and 69W. Enhanced shower activity is expected to continue in the vicinity of the trough. Scattered showers north of 28 between 47W-52W are associated with an upper-level low centered near 31N50W. Surface high pressure located NW of the Azores is in control of the remainder of the central and eastern Atlantic discussion waters. GOES-16 RGB Geocolor imagery continues to show an extensive area of African dust that extends from the west coast of Africa to the eastern Caribbean. The Saharan dust occasionally obscures sky conditions near the Caribbean islands. The dust turns skies hazy, reducing visibility and can result in poor air quality. For additional information please visit http://www.hurricanes.gov/marine $$ ERA