000 AXNT20 KNHC 141805 CCA TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1233 PM EST Sat Jan 14 2017 Corrected header 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 1700 UTC. ...SPECIAL FEATURES... ...Caribbean Sea Gale Warning... A significant pressure gradient between lower pressure across South America and a ridge anchored across the SW North Atlantic is generating gale force winds over the SW Caribbean Sea from 10.5N-12N between 74W-77W with NE winds 30-35 kt and seas 10-12 ft. This gale will linger another 6 hours, then low pressure emerging from the east coast of the United states will weaken the ridge over the western north Atlantic and cause winds in the area to fall below gale force. See latest NWS High Seas Forecast under AWIPS/WMO headers MIAHSFAT2/FZNT02 KNHC for more details. ...MONSOON TROUGH/ITCZ... The monsoon trough extends from the coast of Nigeria near 05N05E to 05N04E. The intertropical convergence zone axis continues from 05N04E to 03N06W to 04N14W, then resumes from 02N20W to 00N29W to north of the coast of South America near 02N47W. Scattered moderate and isolated strong convection is present from 03S-05N between 04E-29W. ...DISCUSSION... ...GULF OF MEXICO... 10-20 kt E to SE surface return flow continues over the Gulf of Mexico. Convergent SE winds are producing patches of scattered showers along the east coast of Mexico. An upper-level ridge extends NE over the Gulf from Bay of Campeche to the Florida big bend. A subsident air mass continues to cover the Gulf. This overall synoptic pattern is expected to persist during the next few days with no new frontal incursions expected. ...CARIBBEAN SEA... Gale conditions continue along the coast of N Colombia. See the special feature section for additional details. Otherwise, a broad ridge of high pressure and deep layer subsidence remains in place across the Caribbean. Fresh to strong winds across the Caribbean will subside slightly during the next day or so in response to the weakening of the ridge to the north, then increase once again on Monday as the ridge rebuilds. ...HISPANIOLA... Fresh to strong NE winds continue across the island and adjacent coastal waters. The winds will decrease slightly during the next day or so as the ridge to the north weakens, then increase once again on Monday. The relatively dry weather pattern will continue as the ridge to the north stays in place. ...ATLANTIC OCEAN... A 1041 mb high is centered over coastal New England. A ridge axis extends WSW to N Florida. A 1011 mb low is centered E of the Lesser Antilles near 22N48W. A surface trough extends NE through the low from 17N54W to 25N41W to 32N39W. Broad surface troughing extends NNE from 06N51W to 22N44W. Scattered convection associated with the low is found from 22N to 24N between 46W and 49W. Scattered convection associated with the trough is situated from 20N to 32N between 34W and 40W. An upper level trough supporting these systems extends SW from 32N42W to 28N45W to 23N56W. During the next 24 hours the upper-level trough will lift to the NE in response to the approach of a broader mid-latitude trough approaching from the west. This will remove the upper-level support for the low to the east of the Lesser Antilles and allow it to dissipate. Otherwise, a frontal boundary is expected to make an incursion into the waters N of 25N and W of 60W, then stall and weaken. For additional information please visit http://www.hurricanes.gov/marine $$ McElroy