Tropical Weather Discussion

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Tropical Weather Discussion NWS National Hurricane Center Miami FL 2237 UTC Sat Mar 28 2020 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 and 2100 UTC surface analyses and satellite imagery through 2300 UTC. ...SPECIAL FEATURES.... ...Caribbean Sea Gale Warning... Tight pressure gradient between low pressure centered over northern Colombia and high pressure centered between Bermuda and the Bahamas will continue to supports nightly gales pulsing off the coast of Colombia through at least Mon night. Seas may reach near 12 ft during each early morning. Please read the latest HIGH SEAS FORECAST: MIAHSFAT2/ FZNT02 KNHC, the latest OFFSHORE FORECAST: MIAOFFNT3/FZNT23 KNHC, or go to the website https://www.nhc.noaa.gov/text/MIAHSFAT2.shtml, from the NWS National Hurricane Center, for more details. ...MONSOON TROUGH/ITCZ... The monsoon trough extends from Sierra Leone near 09N13W to 06N15W. The ITCZ continues from 06N15W to 01N25W to 01N37W to Brazil near 02S45W. Scattered moderate convection is from the Equator to 05N between 25W and 40W. GULF OF MEXICO... Weak ridging extends across the northern Gulf from southwest Florida to the north Texas coast. Recent scatterometer and buoy data indicate moderate to fresh SE winds from Yucatan to the coast of Louisiana, between high pressure over the western Atlantic and a cold front moving southward through Texas and approaching the Texas coast. Buoys are showing 5 to 8 ft seas over much of the western Gulf where winds are stronger. No significant showers or thunderstorms are noted anywhere in the Gulf at this time. Farther south, very warm afternoon temperatures are noted over the Yucatan peninsula, an indication a surface trough will form off the west coast of the Yucatan later this evening. The ridge over the northern Gulf will shift eastward through Sun ahead of the approaching weak cold front. The front will reach the NW Gulf this evening, stall near the Texas and Louisiana coasts Sun, and lift north as a warm front Mon. Strong SE winds will affect the waters adjacent to the northern Yucatan Peninsula this evening and Sun evening as a thermal trough moves westward from the peninsula. A stronger cold front will enter the Gulf early Tue, the cross the northern Gulf by Wed night. CARIBBEAN SEA... Please see the above Special Features section for information on gales off the coast of Colombia. Earlier ship observations and scatterometer satellite data indicated strong to near gale force winds off the coast of Colombia. A concurrent altimeter satellite showed seas to 9 ft in the area of strongest winds, although seas to 10 ft are likely a little farther downstream. Elsewhere, ship and buoy observations along with other scatterometer passes showed moderate to fresh trade winds across the entire basin. Seas are generally 4 to 6 ft. Regional radar showed the usual trade wind showers across mainly the Leeward Islands, Virgin Islands and Puerto Rico, as well as a few near the ABC islands. A sharp upper trough reaches east to west from Puerto Rico to south of Jamaica, supporting a few showers and thunderstorms from west of the southern peninsula to Haiti to south of Jamaica. For the forecast, high pressure centered between the Bahamas and Bermuda will maintain fresh to strong trade winds over the central Caribbean through Tue. Gale force winds will pulse along the Colombian coast each night through Mon night. Fresh to strong winds will also pulse each night over the Gulf of Honduras. ATLANTIC OCEAN... West of 65W, 1022 mb high pressure is centered over the western Atlantic near 29N68W. A cold front extends from 31N49W to 26N53W, where it becomes a stationary front to the eastern Dominican Republic. Fresh trade winds are ongoing mainly south of 22N to the coast of Hispaniola into the Turks and Caicos Islands. Seas are 5 to 7 ft in the open waters outside of the Bahamas. A few fast moving trade wind showers are possible south of the high pressure going toward the southern Bahamas. But otherwise dry conditions persist west of 65W. For the forecast west of 65W, the front will weaken and dissipate by Sun morning. The high pressure will remain nearly stationary through the weekend. Another cold front will move off the southeast U.S coast Mon morning, but stall just off the coast Tue, then weaken and dissipate by Tue night. Strong SW winds are expected north of 25N Tue night and Wed ahead of a strong cold front, which will usher in strong NW winds behind it north of 25N Wed through Thu. Elsewhere over the Atlantic south of 32N, weak 1021 mb high pressure near 29N33W is moving eastward at 15 kt ahead of the cold front near 50W. A few showers and thunderstorms are evident along the cold front north of 29N. Various scatterometer satellite passes over from this afternoon show moderate to fresh trade winds south of 20N and light to gentle winds north of 20N. An altimeter satellite pass from earlier in the day showed a swath 8 to 10 ft seas north of 27N along 55W. This was part of a larger area of northerly swell associated with a developing gale center north of the area. The low is expected to weaken slightly and stay just north of 32N through early next week, but will bring strong NW winds and 10 to 15 ft seas to the region north of 20N between 40W and 55W by late Mon. Farther east, another altimeter pass indicated an area of 6 to 8 ft seas between Senegal and the Cabo Verde Islands, related to northerly swell. Scattered showers and thunderstorms persist south of 05N to the Equator, west of 25W.