000 AXNT20 KNHC 311647 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1147 AM EST Tue Jan 31 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 1200 UTC surface analysis and satellite imagery through 1630 UTC. ...SPECIAL FEATURES... A localized strong pressure gradient is expected to develop in the SW Caribbean Sea by 01/0300 UTC offshore of the coast of Colombia with near gale to gale force E-NE winds occurring late evening and early morning through Wednesday night. 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 05N19W. The Intertropical Convergence Zone extends from 05N19W to the Equator near 34W. Scattered moderate convection is S of 04N between the Prime Meridian and 10W. Widely scattered moderate convection is S of 04N between 26W-53W. ...DISCUSSION... GULF OF MEXICO... Westerly upper level flow prevails over the Gulf basin this afternoon as broad middle to upper level troughing is noted over the SE CONUS stretching westward to over much of Texas. The rather benign upper level pattern is supporting a surface ridge anchored by a 1025 mb high centered near 26N86W. Mostly light to gentle anticyclonic winds are noted E of 90W while gentle to moderate southerly winds are occurring W of 90W. The high center is forecast to remain nearly stationary across the NE Gulf and Florida peninsula through Friday with generally gentle to moderate easterly anticyclonic flow expected. In addition...occasional fresh easterly winds will be possible in the vicinity of the Florida Straits region Thursday night through Saturday as the pressure gradient strengthens slightly. CARIBBEAN SEA... A dissipating stationary front is analyzed from the Windward Passage near 20N73W to the NE coast of Honduras near 16N84W. The front is expected to dissipate fully by tonight. Only a few isolated showers are occurring across the Windward Passage region and NW Caribbean...along with the Gulf of Honduras and interior areas of Belize...Honduras...and Guatemala. Otherwise...the remainder of the Caribbean basin remains fairly tranquil with only a few passing isolated showers possible across the far eastern Caribbean and in the vicinity of the Mona Passage in association with a surface trough extending from 18N68W to 22N65W. These light showers are embedded within moderate to fresh trade wind flow...with slightly stronger trades as noted in the Special Features section above expected within the next 24 hours in close proximity to the coast of Colombia. ...HISPANIOLA... A dissipating stationary front currently extends to the NW of the island across the Windward Passage waters. Isolated showers are occurring within 60 nm NW of the front...while another area of isolated showers is located across the Mona Passage region in association with a surface trough analyzed from 18N68W to 22N65W. The surface trough is expected to cross Hispaniola today providing higher probability of isolated showers this afternoon and evening. Thereafter...NE to E moderate to occasional fresh winds are expected as high pressure anchors to the N across the SW North Atlc region. ATLANTIC OCEAN... Water vapor imagery indicates broad middle to upper level troughing over the eastern CONUS and SW North Atlc region supporting a pair of fronts. The eastern-most cold front extends from 32N56W SW to 24N65W then becomes stationary to the Windward Passage and into the western Caribbean Sea. Widely scattered showers are occurring within 120 nm either side of the front. The secondary front enters the discussion area near 32N60W and extends SW to the Central Bahamas near 25N75W. Ridging continues to build in behind the second front as a 1026 mb high centered across the Florida peninsula is forecast to drift E-NE during the next 24 hours into the SW North Atlc waters. Farther east...across the remainder of the central and eastern Atlc...a surface ridge prevails anchored by a 1030 mb high centered near 30N34W. For additional information please visit http://www.hurricanes.gov/marine $$ HUFFMAN