000 AXNT20 KNHC 282322 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 722 PM EDT FRI OCT 28 2016 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 1800 UTC surface analysis and satellite imagery through 2300 UTC. ...TROPICAL WAVES... Tropical wave extends from 09N49W to 17N48W moving W at 10-15 kt. The wave remains low-amplitude and relatively difficult to track as a result. Subtle 700 mb trough is noted in global model fields between 46W-52W. Isolated moderate convection remains within close proximity to the ITCZ axis from 07N-12N between 41W-51W and continues to be enhanced by the base of an upper level trough with axis extending from 16N47W to 08N53W. Tropical wave extends from 10N73W to 18N71W moving W at 10-15 kt. The wave coincides with 700 mb troughing between 70W-74W and is expected to merge with a broad area of lower pressure across the NW Caribbean Sea by Saturday night into Sunday. Widely scattered moderate convection is from 10N-19N between 70W-75W. ...ITCZ/MONSOON TROUGH... The Monsoon Trough extends from near 15N28W into a 1011 mb low near 13N35W to 10N39W. The Intertropical Convergence Zone axis extends from 10N39W to 08N55W. Scattered moderate and widely scattered strong convection is from 07N-12N between 09W-15W. Isolated moderate convection is from 01N-06N between 10W-25W... and from 11N-16N between 22W-33W. ...DISCUSSION... GULF OF MEXICO... A middle to upper level low is noted on water vapor imagery centered near 26N93W with axis extending from over the lower Mississippi River valley through the upper level low to another upper level low centered over the eastern Pacific waters near 15N100W. This troughing aloft is inducing a weak surface trough analyzed across the SW Gulf from 24N97W to 19N94W providing focus for scattered showers and isolated tstms generally within 90 nm either side of the trough axis. Elsewhere to the east of the upper level troughing...south-southwesterly flow aloft prevails with plenty of cloudiness covering much of the central and eastern Gulf waters...southern Florida peninsula and Florida Straits this evening. Scattered showers and isolated tstms are occurring generally from 23N-29N between 85W-93W...and S of 26N E of 83W...including the Florida Straits. Aside from convection...a strengthened pressure gradient exists between higher pressure across the SE CONUS and an area of low pressure across the NW Caribbean Sea. Fresh to strong easterly winds are expected across central and eastern portions of the basin through Saturday night with slightly weaker winds...moderate to fresh E-NE winds occurring across western portions of the basin through Saturday. CARIBBEAN SEA... Southerly flow aloft prevails between an upper level trough over the western Gulf of Mexico and an upper level anticyclonic circulation centered over the central Caribbean near 16N71W. Within the western periphery of the upper level ridging...a 1010 mb surface low is centered in the NW Caribbean near 19N84W with a surface trough analyzed S-SE from the low to 16N81W to 12N81W. As the wind shear across this region remains unfavorable for organized deep convection in the vicinity of the low...scattered showers and isolated strong tstms are occurring to the NE of the low from 19N-25N between 74W-84W...including much of Cuba. Other isolated showers and tstms are occurring across the north-central Caribbean N of 15N between 68W-77W in association with the upper level diffluent environment...along with the presence of a tropical wave along 73W. Otherwise...outside of the influence of the area of lower pressure across the western portion of the basin...light to gentle trades are expected to persist through the weekend into Monday. ...HISPANIOLA... Upper-level anticyclonic wind flow prevails across the island with widely scattered showers and isolated tstms occurring across the southern and western adjacent coastal waters this evening. This moisture...cloudiness...and precipitation is expected to move across Hispaniola overnight into Saturday. ATLANTIC OCEAN... Upper level south-southwesterly flow prevails aloft over much of the SW North Atlc this evening. Moisture and cloudiness stretch as far E as 55W on the northern periphery of an upper level anticyclonic circulation centered over the central Caribbean Sea near 16N71W. A slowly dissipating stationary front is analyzed from 28N56W W-SW to 27N65W to 25N68W then becomes a shear line to eastern Cuba near 21N76W and providing the primary focus for sustained convection this evening. Scattered showers and tstms are noted on satellite imagery mainly S of 26N W of 65W and within 120 nm either side of the stationary boundary between 55W-65W. Isolated showers and possible isolated tstms are elsewhere S of 30N W of 55W. Aside from the ongoing convection...fresh to strong E-NE winds continue generally north of the frontal boundary W of 65W. Farther east...the remainder of the front E of 55W is analyzed as a stationary front from 33N43W to 28N56W with isolated showers possible within 90 nm either side of the boundary. Finally...across the NE portion of the discussion area...a 1006 mb low is centered SE of the Azores near 36N25W with a surface trough analyzed from the low to 33N21W to 28N24W to 25N32W. Isolated showers and tstms are occurring mainly from 30N-37N between 16W- 22W. For additional information please visit http://www.hurricanes.gov/marine $$ HUFFMAN