000 AXNT20 KNHC 272341 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 641 PM EST Mon Feb 27 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 strengthened pressure gradient is expected to materialize tonight during the late night and early morning hours off the coast of Colombia and re-occur the next several nights. Near gale to gale force E-NE winds are expected as high pressure anchors itself to the N across the SW North Atlc waters for much of the week ahead. 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 09N13W to 03N19W. The Intertropical Convergence Zone axis extends from 03N19W to 01N24W to the Equator near 30W. Widely scattered moderate and isolated strong convection is from 02N-05N between 10W-14W...and S of 06N between 18W-28W. Scattered moderate convection is S of 06N between 31W-49W. ...DISCUSSION... GULF OF MEXICO... Water vapor imagery indicates mainly dry air aloft within mostly zonal flow over the Gulf basin this evening. At the surface...the southwestern periphery of ridging anchored across the SW North Atlc remains in control across the basin with a weak frontal boundary extending across the SE CONUS. Mostly gentle to moderate E-SE winds prevail as clear skies are noted on visible satellite imagery across a majority of the forecast waters. A few isolated showers are however possible across the NW waters N of 27N W of 91W in maximum low-level moisture convergence. In addition...a few isolated showers are possible across the Yucatan peninsula and adjacent coastal waters of the Yucatan channel in association with a surface trough analyzed from 18N89W to 22N87W. Moderate to occasional fresh southerly return flow is forecast to persist across the Gulf through Wednesday morning. By Wednesday afternoon...the next cold front will emerge off the Texas and Louisiana coasts providing a new round of fresh to occasional strong N-NE winds in wake of the front as it sweeps E-SE and stalls across central portions Thursday night. A reinforcing front will then push southward off the coastal plain into early Friday with fresh to strong E-NE winds occurring across much of the basin through Saturday night. CARIBBEAN SEA... Upper level ridging prevails over the Caribbean basin this evening as water vapor indicates mostly dry air within an overall subsident and stable environment. One area of interest is a surface trough analyzed across the Yucatan peninsula and Belize from 16N88W to 22N87W. This troughing is providing focus for isolated low-topped showers across the NW Caribbean waters from 19N-22N W of 85W. The boundary will drift westward and weaken across the SW Gulf of Mexico waters overnight into early Tuesday. Farther east...quick moving isolated showers are possible through the overnight hours into Tuesday across the SE Caribbean waters S of 14N E of 65W. Otherwise...aside from the Special Features near gale to gale force winds expected off the coast of Colombia each night...fresh to occasional strong trades are expected to persist through much of the week as high pressure anchors itself to the N across the SW North Atlc region. ...HISPANIOLA... Currently fair conditions and partly cloudy skies prevail across the island this evening. Water vapor imagery also indicates very dry air and overall strong subsidence over the region. ATLANTIC OCEAN... Water vapor imagery shows middle to upper level trough progressing over the central North Atlc waters supporting a cold front entering the discussion area near 32N58W. The front extends SW to 30N65W with only a few possible isolated showers occurring within 45 nm either side of the front. A pre-frontal surface trough extends in the vicinity of the front near 35N49W to 27N60W with isolated showers occurring within 90 nm either side of the boundary. The remainder of the SW North Atlc is under the influence of a surface ridge anchored by a 1033 mb high centered off the mid-Atlc coast near 37N68W. Moderate to occasional fresh anticyclonic winds are noted on recent scatterometer data within the southern periphery of this ridge across the discussion waters. Farther east...the eastern Atlc is under the influence of a surface ridge anchored by a 1028 mb high centered S of the Azores near 35N30W. One weakness within the ridging...is a dissipating surface trough boundary extending from 32N41W to 28N46W. Isolated showers are possible N of 26N between 39W-46W. For additional information please visit http://www.hurricanes.gov/marine $$ HUFFMAN