000 AXNT20 KNHC 050557 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 157 AM EDT Sat Aug 5 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 0515 UTC. ...SPECIAL FEATURES... A 1012 mb low is several hundred miles southwest of the Cabo Verde Islands near 10N31W. The low is moving west at 5 kt within the last 24 hours. The low is in a region of low vertical wind shear. CIRA LPW imagery shows a very moist environment around the low. Scattered showers are within 90 nm of the low center. There is a medium chance for this system to become a tropical depression by early next week across the eastern or central tropical Atlc. ...TROPICAL WAVES... A tropical wave is over the E Atlantic with axis extending from 17N33W to 08N33W, moving W at 10 kt. This wave has broken away from the special feature low mentioned above. The wave is in a moist environment. Dry Saharan air is noted N of 18N. A surface trough depicts the wave axis. Scattered moderate convection is from 09N-12N between 33W-38W. A tropical wave is in the central Atlantic with axis extending from 20N45W to 09N46W, moving west at 10 kt. The wave is in a moist environment as seen on SSMI TPW imagery. The wave has a 700 mb trough W of the current position. The wave is in a region of low vertical wind shear. No significant convection is noted at this time. A tropical wave is in the central Caribbean with axis extending from 18N72W to 09N72W, moving west at 10 kt. The wave is in a very moist environment as seen on SSMI TPW imagery. The wave is under a distinct 700 mb trough. The wave is in a region of strong vertical wind shear. Scattered moderate to isolated strong convection is over the S Caribbean and N Colombia from 07N-14N between 72W-77W. ...ITCZ/MONSOON TROUGH... The monsoon trough extends from the African coast near 14N17W to 14N22W to 10N31W to 13N43W. The Intertropical Convergence Zone axis extends from 12N48W to 10N55W to 10N62W. Aside from convection associated with the tropical waves, scattered moderate convection is from 08N-12N between 55W-59W. ...DISCUSSION... GULF OF MEXICO... A 1014 mb low is centered inland over S Mississippi near 32N90W. Scattered showers linger over the N Gulf of Mexico N of 28N. Further S, a surface trough is over the Yucatan Peninsula from 21N89W to Guatemala near 14N92W. Scattered moderate to strong convection is over the Bay of Campeche from 17N-20N between 91W- 93W. In the upper levels, a broad upper level trough is over the N Gulf N of 27N with upper level moisture and cloudiness. Expect over the next 24 hours for airmass showers and thunderstorms to form over the N Gulf during the afternoon and evening hours Sat. CARIBBEAN SEA... A tropical wave is moving across the central Caribbean. See above. Fresh to strong winds are in the vicinity of this wave. Scattered showers and isolated thunderstorms linger over the W Caribbean and Central America. In addition the extension of the Pacific monsoon trough is producing scattered moderate convection over the SW Caribbean, Panama, and Costa Rica, S of 11N. Further more, scattered showers are over the NE Caribbean between 62W-73W. Of note in the upper levels, a small upper level low is centered over Hispaniola near 18N72W. Upper level diffluence E of the center is enhancing the showers over the NE Caribbean. Expect over the next 24 hours for the Caribbean and Central America to remain in a very moist environment S of 18N, and thus showers and thunderstorms will build during the afternoon and evening hours Sat. ...HISPANIOLA... Scattered showers are occurring across the Island mainly S of 19N. This shower activity is associated with a tropical wave moving over the central Caribbean. The tropical wave is expected to be W of the island by Saturday night, however shower activity is forecast to linger through early Sunday morning. ATLANTIC OCEAN... A tropical low and two tropical waves are over the tropical Atlantic. See above. Scattered showers linger along the N Florida coast N of 29N W of 79W. Otherwise, the remainder of the Atlantic is under the influence of three surface highs anchored near 29N69W, 30N53W, and 34N28W. Of note in the upper levels, an upper level low is centered near 24N56W with upper level diffluence S and W of the center producing scattered showers. For additional information please visit http://www.hurricanes.gov/marine $$ Formosa