000 AXNT20 KNHC 070557 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1257 AM EST Wed Mar 7 2018 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 0000 UTC surface analysis and satellite imagery through 0530 UTC. ...SPECIAL FEATURES... Atlantic Gale Warning A cold front extends from 31N46W to 25N60W. A dissipating frontal boundary extends from that point to 28N67W. Latest scatterometer data depicts gale-force westerly winds north of 30N between 50W- 60W. Seas in this area will range between 25-29 ft. These conditions are expected to continue through late Wednesday. Please read the Atlantic High Seas Forecast under the AWIPS header MIAHSFAT2, and under the WMO header FZNT02 KNHC for more details. Another area of gale-force winds is expected to develop by Wednesday afternoon over the west Atlantic mainly north of 28N and within 120 nm east of a front that will extend at that time from 31N75W to 27N80W. Seas in this area will range between 13-16 ft. These conditions will continue through late Wednesday. Please read the Atlantic High Seas Forecast under the AWIPS header MIAHSFAT2, and under the WMO header FZNT02 KNHC for more details. ...MONSOON TROUGH/ITCZ... The monsoon trough passes through coast of Africa near 06N10W to 03N14W. The ITCZ continues from that point to 02N28W to 03S40W. Scattered moderate convection is from 02N-05N between 10W-20W. ...DISCUSSION... GULF OF MEXICO... A cold front extends across the northern half of the basin 30N85W to 24N97W. Abundant cloudiness and scattered showers accompany this frontal boundary affecting the area north of 26N. Surface ridging prevails north and south of the front. The front will reach from northern Florida to the Bay of Campeche at sunrise today, then continue moving southeast across the basin through the day. Strong to near gale northerly winds across the northwest Gulf waters will prevail today, and then subside by Thursday as the front moves away and the pressure gradient weakens. Southerly return flow will set up across the northwest Gulf on Thursday night, and spread eastward across the entire Gulf by late Friday, ahead of the next cold front expected to move into the northern waters by late Saturday. CARIBBEAN SEA... The remnants of a frontal boundary were analyzed as a surface trough that extends over the Leeward Islands along 16N and east of 63W. Scattered showers are noted near this boundary affecting the islands and adjacent waters. Surface ridging prevails across the remainder of the basin. Scatterometer data depicts gentle to moderate trades across most of the area except south of 12N between 73W-77W where moderate to fresh winds prevail. Large northerly swell propagating southward through the northern Caribbean Sea passages, and through the tropical waters to the east of the Lesser Antilles, will subside gradually this week. The surface pressure gradient will tighten during the next few days, with strong trade winds forecast across the south-central Caribbean through the upcoming weekend. ATLANTIC OCEAN... Please refer to the Special Features section for more details about the ongoing event of gale-force winds over the central portion of the basin and the upcoming gale-wind event over the western Atlantic. High pressure prevails across the western Atlantic centered near 27N73W. A cold front extends from 31N46W to 25N60W. A dissipating frontal boundary extends from that point to 28N67W. To the east, another frontal boundary was analyzed extending from 31N29W to 16N55W. A surface trough continues from that point to 16N61W. Minimal convection is observed with these fronts. Surface anticyclonic flow covers the remainder of the basin anchored by a 1021 mb high centered near 23N31W. Large northerly swell will continue across the entire exposed waters through today. Strong southerly winds have developed north of the Bahamas ahead of a cold front currently approaching from the west. This front will move offshore into the west Atlantic today with gale conditions developing north of 30N and east of the front. The front will reach from Bermuda to the central Cuba by Thursday morning, and from 27N65W to Hispaniola by Friday morning. A second cold front will move eastward, across the waters north of the Bahamas on Thursday, and merge with the first cold front across the tropical waters north of Puerto Rico late on Friday. For additional information please visit http://www.hurricanes.gov/marine $$ ERA