000 AXNT20 KNHC 041625 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1225 PM EDT Fri Aug 4 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 1200 UTC surface analysis and satellite imagery through 1415 UTC. ...SPECIAL FEATURES... A tropical wave extends from 09N29W to 17N33W moving W at 5-10 kt. The wave coincides with 700 mb troughing between 30W-38W with a stretched maximum in 850 mb relative vorticity focused on a 1012 mb low centered at the southern extent of the wave near 09N29W. Another nearby surface low at 1010 mb is to the east analyzed along the monsoon trough near 10N26W. Widely scattered moderate convection is from 08N-13N between 25W-33W. Environmental conditions are forecast to be conducive for consolidation of convection and further development...and a tropical depression is likely to form by early next week across the eastern or central tropical Atlc. This system has a medium chance for development within the next 48 hours. ...TROPICAL WAVES... A tropical wave extends from 10N50W to 18N45W moving W at 5-10 kt. The wave coincides with relatively broad 700 mb troughing between 42W-52W. The areal extent of the Saharan Air Layer across the central tropical Atlc is inhibiting any significant deep convection with the wave at this time. A tropical wave extends from 10N70W to 20N70W moving W at 5-10 kt. The wave continues moving within the southern periphery of a mid-level ridge anchored over the SW North Atlc near 28N72W. Scattered moderate convection...likely enhanced due to ample upper level diffluence over the NE Caribbean Sea...is occurring from 13N-18N between 65W-72W. ...ITCZ/MONSOON TROUGH... The monsoon trough extends from the African coast near 15N17W to 09N30W to 11N40W. The Intertropical Convergence Zone axis extends from 11N40W to 12N44W to 07N58W. Aside from convection associated with the tropical waves...isolated moderate convection is from 06N-12N between 21W-37W...and from 07N-13N between 50W-61W. ...DISCUSSION... GULF OF MEXICO... A middle to upper level trough is noted on water vapor imagery over the SE CONUS this afternoon with the base of the trough extending over the north-central and NW Gulf waters. The troughing supports a surface trough extending from eastern Louisiana SW to near Corpus Christi Texas. Low-level moisture convergence is maximized along this boundary with scattered showers and tstms occurring mainly N of 26N and across inland portions of SE Louisiana...southern Alabama...and northern Florida...including the panhandle region. The boundary is expected to remain nearly stationary through Saturday night along the coast...then lift northward and dissipate Sunday. Elsewhere...a surface ridge extends across the central Florida peninsula to the east-central coast of Mexico near 21N97W. Mostly clear skies and fair conditions are expected to persist with the ridge remaining in place across the basin through Monday of next week. CARIBBEAN SEA... A tropical wave is moving across the central Caribbean along 70W generating a broad area of scattered showers and isolated tstms generally N of 13N E of 72W. Elsewhere...low-level moisture convergence of moderate to fresh trades is generating scattered showers and tstms from 13N-19N between 81W-90W...including inland portions of Central America. As the tropical wave moves westward...fresh to strong winds are expected to accompany the wave with continued strong convection through Monday. ...HISPANIOLA... Scattered showers and tstms are occurring across the southern adjacent coastal waters due to a tropical wave along 70W. The tropical wave is expected to pass S of the island through late tonight and then across the remainder of the central Caribbean into the western Caribbean on Saturday. Continued scattered showers and tstms are expected across the region with any lingering activity moving into the western Caribbean during the upcoming weekend. ATLANTIC OCEAN... Across the SW North Atlc...an upper level ridge remains anchored in the vicinity of 30N70W supporting a ridge axis extending from a 1026 mb high near 30N51W to the central Florida peninsula and into the southern Gulf of Mexico. Mostly fair skies and tranquil conditions prevail with only a few possible isolated showers and tstms occurring NW of a line from Cape Canaveral Florida to 32N77W as a mid-level shortwave trough moves over the Outer Banks region today. Another area of scattered showers and isolated tstms is occurring in the vicinity of a surface trough analyzed from 36N61W to 31N63W. This convection covers the area N of 28N between 60W- 66W. The ridge is forecast to move northward slightly and keep any significant deep convection generally N of the discussion area. Otherwise...the remainder of the central and eastern Atlc is under the influence of a surface ridge anchored by the aforementioned 1016 mb high and another 1025 mb high centered S of the Azores near 33N29W. For additional information please visit http://www.hurricanes.gov/marine $$ HUFFMAN