000 AXNT20 KNHC 241204 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 804 AM EDT Sat Mar 24 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 0600 UTC surface analysis and satellite imagery through 1115 UTC. ...SPECIAL FEATURES... ...GALE WARNING FOR THE SOUTH-CENTRAL CARIBBEAN SEA... A combination of strong surface high pressure ridging southward along the U.S. east coast and relatively strong low pressure over northern South America supports winds to gale force near the coast of Colombia. The gale force winds will not be continuous but are expected to recur each night during the evening and overnight hours through the end of next week while this surface weather pattern persists. Presently a gale is from 11N to 12N betwen 74W and 76W, with seas 9 to 12 ft. For more details please see High Seas Forecasts issued by the National Weather Service under AWIPS/WMO headers MIAHSFAT2/FZNT02 KNHC. This information can also be found at the following website: www.nhc.noaa.gov/marine ...GALE WARNING for the METEO-FRANCE areas... Please refer to the METEO-FRANCE High Seas Forecast, that is listed on the website: WWW.METEOFRANCE.COM/PREVISIONS-METEO- MARINE/BULLETIN/GRANDLARGE/METAREA2. Gale-force winds are forecast to develop by 00Z Sun for the following areas: AGADIR and TARFAYA. This is expected to be a relatively prolonged event and gale conditions could persist in these areas until 00Z Tue. ...MONSOON TROUGH/ITCZ... The monsoon trough extends from Guinea on the African coast near 10N13W to 04N20W. The ITCZ continues from 04N20W to 02N24W to 01N31W to the northeast coast of Brazil near 02S44W. Scattered moderate convection is from 2N-6N between 04W-22W, and from 3S-4N between 40W-51W. ...DISCUSSION... GULF OF MEXICO... Fair weather prevails across the entire Gulf of Mexico with a 1024 mb surface high pressure centered over N Florida near 29N82W. Abundant dry air is in the mid-and upper-levels of the atmosphere enhancing the dry weather pattern. Moderate to fresh surface winds are out of the northeast to east over the eastern and central Gulf and east to southeast over the western Gulf. Sea heights are highest, near 7 ft, in the NW Gulf due to the longer fetch there. The area of surface high pressure is expected to gradually shift ESE during the next several days, causing winds to veer from the south over much of the region. This flow will cause sea heights to increase a little over the northwestern waters. Surface troughing is expected to develop over the Yucatan Peninsula each day, then migrate W into the Bay of Campeche during the evening and nighttime hours. Otherwise, fair weather is expected to continue through the weekend as dry air remains in place. CARIBBEAN SEA... Undersea volcano Kick'em Jenny, north of Grenada near 12.18N 61.38W, is in a state of unrest. The government of Grenada advises mariners to observe a 5 km or 3.1 nm exclusion zone around Kick'em Jenny. Please refer to the web page, www.nadma.gd, for additional information. Relatively quiet conditions exist across the Caribbean Sea as mid-to upper-level ridging maintains a relatively dry and subsident weather pattern over the basin. Trade winds are strongest over the south-central waters N of the coast of Colombia. Winds are expected to reach gale force during the evening and overnight hours through Thu night and Fri morning. See the SPECIAL FEATURES section above for more details. Otherwise, ridging extending southward from along the east coast of the united States will maintain moderate to fresh NE to E winds over the Caribbean basin through the first half of next week. ATLANTIC OCEAN... A slow moving cold front enters the discussion area near 32N57W and continues southwestward to 24N64W. Scattered showers and isolated thunderstorms are observed along and up to 60 nm SE of the front N of 25N, while cloudiness and patchy rain are seen along and up to 90 nm NW of this boundary N of 25N. West of the front, surface high pressure dominates the area with NW to NE flow and cooler air covering the western Atlantic. Expansive surface high pressure dominates the central and eastern Atlantic Ocean. A strong 1032 mb high is centered over the E Atlantic near 35N34W with a ridge extending WSW to NE of the Leeward Islands near 24N55W. This high is producing fresh trade-wind flow across a large portion of the tropical and subtropical eastern Atlantic waters, except for the waters W of 55W, where moderate trades are noted. An upper-level low is centered near 25N35W. The front over the central-western Atlantic is expected to slowly shift eastward and weaken while another boundary enters the far northwestern waters this weekend. For additional information please visit http://www.hurricanes.gov/marine $$ Formosa