000 AXNT20 KNHC 240604 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 204 AM EDT Sat Jun 24 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 0545 UTC. ...TROPICAL WAVES... A tropical wave is in the E Atlc with axis extending from 18N26W to 06N28W, moving W at 15-20 kt within the last 24 hours. The wave is in a region of favorable to neutral wind shear. However, the CIRA LPW imagery show extensive dry air in the wave environment, which coincide with Meteosat enhanced imagery of Saharan dry air and dust. This is supporting lack of convection at the time. A tropical wave is in the central Atlc with axis extending from 12N48W to 04N49W, moving W at 15-20 kt within the last 24 hours. The wave is in a region of favorable to neutral wind shear S of 11N, is in a moderate moist environment with some patches of dry air according to CIRA LPW, and is under a region of upper level divergence. These factors support scattered showers and isolated tstms from 3N to 12N between 46W and 58W. A tropical wave is in the E Caribbean with axis extending from 14N65W to inland Venezuela, moving west at 10-15 knots within the last 24 hours. The wave is in a region of favorable wind shear. However, extensive intrusion of Saharan dry air and dust in the wave environment hinder convection at the time. ...MONSOON TROUGH/ITCZ... The Monsoon Trough extends from 08N13W to 08N16W. The Intertropical Convergence Zone axis begins near 05N30W to 03N40W to 05N49W. Aside from convection associated with the tropical waves...scattered moderate convection is from 04S-07N between 33W-46W. Numerous heavy showers and scattered tstms are from 05N-09N E of 14W. ...DISCUSSION... GULF OF MEXICO... Stable weather conditions are basin-wide being supported by surface high pressure extending SW from the W Atlc and dry air subsidence from aloft as indicated by Water Vapor imagery. The ridge supports moderate to fresh E-SE winds across the basin, which are forecast to continue through Sunday. The only exception is the area from 21N to 23N between 87.5W and 90.5W where NE-E fresh to strong winds are present, however with seas less than 8 ft. This area of fresh to strong winds is forecast to diminish within the next 12 hours. An upper level low centered W of the Yucatan Peninsula will support showers over the Bay of Campeche and the NW Gulf over the weekend. Otherwise, by Saturday night into Sunday...a weak frontal boundary is expected to impact the northern waters as it stalls along 30N and dissipates by Sunday night. CARIBBEAN SEA... An upper level low is centered over the E Bay of Campeche continue to support scattered to isolated showers over Honduras and the NW Caribbean W of 80W. The presence of a tropical wave across southern Mexico is generating heavy showers across Guatemala. Another tropical wave is in the SE Caribbean, however lacking convection due to abundant Saharan dry air and dust in the region. The northern portion of this wave is analyzed as a surface trough across the Leeward Islands where it generates isolated showers. Otherwise, fresh to strong winds will continue in the south- central basin, increasing to near gale force on Sunday as the tropical wave moves into this area. Moderate to fresh trades are elsewhere. Little change is expected thereafter for the early portion of next week. ...HISPANIOLA... Mostly clear skies prevail across the island as surface ridging to the N across the SW North Atlc remains in place providing mostly fair weather conditions. However, a surface trough moving along the periphery of the Atlc surface ridge will bring moisture across the region, thus supporting showers Saturday and Sunday. ATLANTIC OCEAN... An upper level anticyclonic circulation is centered offshore of NE Florida that continues to support a 1021 mb high centered near 30N67W. Otherwise, the remainder of the central and eastern Atlc is under the influence of surface ridging anchored by a 1030 mb high centered N of the Azores near 39N27W. There are two tropical waves in the basin. See that section above for further details. For additional information please visit http://www.hurricanes.gov/marine $$ Ramos