000 AXNT20 KNHC 112254 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 554 PM EST Sat Feb 11 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 2230 UTC. ...SPECIAL FEATURES... The regional pressure gradient between ridging anchored across the SW North Atlc...including the Florida peninsula...and lower pressure across northern South America is forecast to support near gale to gale force E-NE winds tonight into Sunday morning. The wind field off the coast of Colombia is expected to pulse during the late night and early morning hours again Sunday night into Monday morning. 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 10N14W to 03N19W. The Intertropical Convergence Zone axis extends from 03N19W to the Equator near 32W. Scattered moderate convection is from 02N-08N between 03W-14W...S of 06N between 18W-30W...and S of 03N between 30W-41W. ...DISCUSSION... GULF OF MEXICO... Water vapor imagery indicates mostly dry air aloft within a middle to upper level ridge anchored over the basin. Conditions remain fairly tranquil at the surface as the western periphery of a ridge anchored across the SW North Atlc on a 1028 mb high centered near 29N71W is providing mostly gentle to moderate S-SE winds. The ridge is expected to influence the basin until Sunday night. By Sunday night into Monday morning...the next frontal boundary is forecast to emerge off the Texas and Louisiana coasts providing a brief period of N-NE winds across the northern waters...quickly rebounding as an area of low pressure develops across northern Mexico late Monday into Tuesday. CARIBBEAN SEA... An upper level trough is noted on water vapor imagery over the central Atlc that stretches SW to a broad base over Hispaniola. The front supported by the troughing remains N of Hispaniola and Puerto Rico...however lingering low-level moisture and cloudiness extends across Hispaniola SW to Jamaica then to the coast of Nicaragua. Isolated showers are possible within this 180 nm wide corridor. In addition...isolated showers are occurring off the coast of Yucatan peninsula and across the south-central and SE portions of the basin. Otherwise...the remainder of the Caribbean is under mostly moderate to fresh trades outside of the Special Features area off the coast of Colombia. The trades are expected to gradually weaken into gentle to moderate breeze levels by late Monday as high pressure anchored to the N across the SW North Atlc weakens. ...HISPANIOLA... A stationary front extends along 20N between 67W-73W providing focus for low-level moisture convergence and widely scattered showers occurring across the island this evening. The front will be slow to dissipate through Monday providing an increased probability of showers and possible isolated tstms Sunday and Sunday night. ATLANTIC OCEAN... A middle to upper level trough is noted on water vapor imagery over the central Atlc with axis extending from 32N48W to 25N54W to a broad base over Hispaniola and vicinity. The troughing supports a cold front analyzed from 32N46W SW to 27N53W then stationary to N of Hispaniola near 20N70W. Scattered showers and widely scattered tstms are occurring primarily N of 26N between 41W and the front...while widely scattered showers are occurring within 90 nm either side of the front W of 52W. To the west of the front... ridging influences a majority of the SW North Atlc anchored by a 1028 mb high centered near 30N70W. Otherwise...the remainder of the eastern Atlc is under the influence of a surface ridge anchored by a 1022 mb high centered near 30N38W and a complex 992 mb low centered SW of the Iberian peninsula near 36N11W. Several waves of mid-level energy continues to rotate around the southern periphery of the low pressure area with isolated showers and tstms remaining mainly N of 28N E of 22N. A cold front S of the Azores producing near gale to gale force northerlies is expected to enter the discussion area during the next 6 to 12 hours between 20W-30W. For additional information please visit http://www.hurricanes.gov/marine $$ HUFFMAN