000 AXNT20 KNHC 221037 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 637 AM EDT SAT OCT 22 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 0600 UTC surface analysis and satellite imagery through 1000 UTC. ...SPECIAL FEATURES... As of 22/0900 UTC...a cold front extends across the Gulf of Mexico from 26N81W to 24N90W to 21N97W generating near gale to gale force NW to N winds generally S of 21N W of a surface trough analyzed from the front near 22N97W to 19N94W. These conditions are expected to continue through Saturday afternoon across portions of the SW Gulf of Mexico. See latest NWS High Seas Forecast under AWIPS/WMO headers MIAHSFAT2/FZNT02 KNHC for more details. ...TROPICAL WAVES... Tropical wave extends from 09N48W to 18N43W moving W at 10-15 kt. The wave coincides with global model indicated 700 mb troughing between 42W-51W with a maximum in 850 mb relative vorticity along the wave axis near 11N. Scattered moderate and isolated strong convection is from 07N-16N between 38W-51W. ...ITCZ/MONSOON TROUGH... The Monsoon Trough extends from the African coast near 12N16W to 09N20W. The Intertropical Convergence Zone axis extends from 09N20W to 05N30W to 07N43W to 10N47W to 07N58W. Aside from convection associated with the tropical wave along 46W...widely scattered moderate convection is from 05N-13N between 19W-38W. ...DISCUSSION... GULF OF MEXICO... A middle to upper level trough is noted on water vapor imagery with axis extending from over the Carolinas S-SW to a broad base over the NE Gulf waters near 27N84W. The troughing supports a cold front analyzed across the southern Florida peninsula to 24N90W to 21N97W and inland as a stationary front across interior portions of east-central Mexico. Widely scattered showers and isolated tstms are occurring across the SW Gulf waters generally S of 24N W of 91W in association with the front...in addition to the near gale to gale force NW to N winds mentioned above in the Special Features section. High pressure continues to build in across the lower Mississippi River valley this morning and will gradually drift eastward across the SE CONUS through Monday. Aside from the localized gale force wind conditions expected across the SW Gulf...elsewhere moderate to fresh N-NE winds are expected to persist through Sunday gradually veering NE to E Sunday late into early Monday then mostly E to SE on Monday as the ridge shifts eastward. CARIBBEAN SEA... A weak middle to upper level shortwave trough is noted on water vapor imagery with axis extending over the central and SE Bahamas SW to a broad base over the NW Caribbean waters near 19N84W. The troughing supports a surface trough analyzed from across eastern Cuba near 20N74W S-SW to across Jamaica then into the SW Caribbean near 13N81W. Scattered showers and isolated tstms are occurring within 75 nm either side of a line from the Windward Passage near 20N74W to 13N78W. Otherwise...the remainder of the NW Caribbean is under the influence of fair conditions and gentle to moderate N winds for Saturday. A cold front moving SE across the Gulf of Mexico is expected to reach the NW Caribbean by early Sunday morning increasing NE winds across the region into the moderate to occasional fresh breeze range Sunday into Sunday night. Elsewhere...the eastern and central Caribbean are under mostly fair skies this morning with moderate to fresh trades prevailing. These trades are expected to persist through Monday. ...HISPANIOLA... Currently isolated showers and possible tstms are occurring across the island with a line of scattered showers and tstms to the NW of the island stretching from the across the Turks and Caicos Islands SW through the Windward Passage to the SW coast of Haiti near 18N75W. This activity is in association with a surface trough analyzed from 22N72W SW to eastern Jamaica near 18N77W. This troughing is supported aloft by a middle to upper level shortwave trough progressing eastward over the SE Bahamas. Increased probability of scattered showers and tstms is expected through Sunday as the troughing lingers across the region. ATLANTIC OCEAN... The Special Features cold front continues to move eastward across the far NW portion of the SW North Atlc region with a mid-level shortwave supporting a 997 mb low centered near 35N70W and associated surface trough extending from the low S-SW to 30N70W to the SE Bahamas near 24N76W to central Cuba near 22N78W. Isolated showers and possible isolated tstms are N of 27N between 66W-72W. Farther SE...another weaker frontal trough extends from 23N71W to the Windward Passage region generating scattered showers and strong tstms generally from 19N-25N between 65W-74W. The main cold front is expected to merge with the easternmost two frontal troughs by Sunday as ridging builds in across the western portion of the SW North Atlc. By Monday...the cold front will weaken slightly and become stationary between 57W-64W across the central Atlc. Otherwise...the remainder of the central and eastern Atlc currently is under the influence of surface ridging anchored by a 1032 mb high centered well N of the discussion area SE of Newfoundland Canada near 44N44W. One exception is a weakening cold front analyzed from near 32N14W SW to 27N29W then stationary westward to 25N43W. Isolated showers and possible tstms are within 90 nm either side of the stationary front. This activity is supported aloft by a middle to upper level low centered near 24N40W. For additional information please visit http://www.hurricanes.gov/marine $$ HUFFMAN