000 AXNT20 KNHC 082320 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 620 PM EST SUN JAN 8 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 1800 UTC surface analysis and satellite imagery through 2300 UTC. ...SPECIAL FEATURES... A cold front is currently analyzed across the SW North Atlc and western Caribbean Sea from 32N65W S-SW to eastern Cuba near 20N76W to the northern coast of Honduras near 16N87W and supported aloft by a middle to upper level trough axis extending from over the mid-Atlc coastal waters near 37N74W S-SW to over the southern Florida peninsula near 27N82W. Strong to near gale force northerly winds prevail W of the front across portions of the SW North Atlc and NW Caribbean Sea...while near gale to gale force winds are expected to materialize in the Windward Passage region and areas downwind of the N-NE flow to the E of Jamaica by 09/1800 UTC. This gap wind flow is expected to persist through Tuesday. See latest NWS High Seas Forecast under AWIPS/WMO headers MIAHSFAT2/FZNT02 KNHC for more details. ...ITCZ/MONSOON TROUGH... The Monsoon Trough extends from the African coast near 10N15W to 07N19W. The Intertropical Convergence Zone axis extends from 07N19W to 03N30W to the Equator near 38W. Isolated moderate convection is from the Equator to 07N between the Prime Meridian and 09W. Scattered moderate convection is from 03N-09N between 20W-29W. ...DISCUSSION... GULF OF MEXICO... An upper level trough axis extends from over the southern Florida peninsula SW to over southern Mexico near 18N96W and into the eastern Pacific region. While the surface frontal boundary associated with this upper level troughing has moved east of the basin...strong high pressure to the W of the front continues to provide strong to near gale force NE winds across portions of the SE Gulf waters...while moderate to fresh NE to E winds continue elsewhere. The ridging in place is anchored by a pair of strong 1043 mb high centered over the Ohio River and lower Mississippi River valleys this evening. In addition...a 1040 mb high is also centered across east-central Mexico near 22N98W. Finally... overnight into Monday SE return flow is forecast to re-establish itself across the NW Gulf and gradually spread eastward through Monday night. A surface ridge axis is expected to extend from offshore of the Carolinas near 32N74W SW to 23N98W through Wednesday. CARIBBEAN SEA... Southwesterly flow aloft prevails W of 68W between an upper level trough over the Gulf of Mexico and an upper level ridge over the eastern Caribbean with axis extending from 12N68W N-NE to beyond 25N60W. The troughing supports a cold front analyzed from eastern Cuba near 20N76W SW to northwestern Honduras near 15N88W. Widely scattered showers are occurring within 120 nm either side of the front generally W of 80W. W of the front...strong to near gale N-NE winds prevail with the area of developing gale force winds expected in the Windward Passage region by Monday afternoon. Otherwise...moderate to fresh trades prevail elsewhere with slightly stronger...fresh to strong...trades occurring within close proximity to the coast of Colombia and eastern Panama. The front is expected to continue gradually moving eastward through mid-week with fresh to strong NE to E winds prevailing W of the front as it becomes diffuse by Thursday. ...HISPANIOLA... A cold front lies to the NW of the island this evening analyzed from the SE Bahamas to eastern Cuba and into the western Caribbean Sea. Near gale to gale force N-NE winds are forecast to develop in the Windward Passage region and areas to the E of Jamaica by Monday afternoon into evening with the frontal passage. Otherwise...cloudiness will increase with the approach of the front as well as the probability of isolated showers. By Monday night...winds will remain brisk...however skies will begin to improve into Tuesday as high pressure builds across the region. ATLANTIC OCEAN... A middle to upper level trough continues to move off of the eastern U.S. seaboard this evening in support of a cold front analyzed from 32N65W SW to the SE Bahamas then to eastern Cuba. Scattered showers and isolated tstms are occurring N of 24N within 90 nm either side of the front. Otherwise...strong to near gale force northerly winds follow in wake of the front as high pressure anchored itself across the SE and mid-Atlc regions of the CONUS. The front is expected to move eastward through Tuesday night when cyclogenesis is forecast to occur in the vicinity of 28N57W. The associated low pressure area is expected to drift southward through the remainder of the week and possibly impact the Lesser Antilles by next weekend. Otherwise...the central Atlc is under the influence of a ridge anchored by a 1029 mb high centered near 35N43W. The ridge axis extends SW from the high to 25N62W. Lastly...a broad middle to upper level low is noted on water vapor imagery over the eastern Atlc centered near 30N28W. The upper level low continues to support a nearly collocated 1011 mb surface low centered near 29N27W. A few isolated showers and possible tstms are occurring N of 30N between 16W-31W. For additional information please visit http://www.hurricanes.gov/marine $$ HUFFMAN