000 AXNT20 KNHC 271807 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1805 UTC Tue Oct 27 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 1200 UTC surface analysis and satellite imagery through 1700 UTC. ...SPECIAL FEATURES... Tropical Storm Zeta has emerged into the southern Gulf of Mexico from the Yucatan Peninsula near 22.1N 90.1W at 27/1800 UTC or 420 nm S of the Mouth of the Mississippi River. Zeta is moving NW at 12 kt. Estimated minimum central pressure is 985 mb. Maximum sustained wind speed is 55 kt with gusts to 65 kt. Scattered moderate to strong convection is within 300 nm of the center in the NE quadrant and 360 nm SE quadrant. Scattered moderate and isolated strong convection is within 270 nm of the center in the SW quadrant and 210 nm NW quadrant. An additional band of scattered moderate to strong convection extends S along the east coast of Nicaragua and NE Honduras. On the forecast track, the center of Zeta will move over the southern Gulf of Mexico today while restrengthening to a hurricane. Zeta will move northward over the central Gulf of Mexico tonight, then accelerate and make landfall along the northern Gulf coast late Wednesday or Wednesday night. Zeta will weaken rapidly as it moves inland across the SE United States early Thursday. Please read the latest High Seas Forecast issued by NHC at website https://www.nhc.noaa.gov/text/MIAHSFAT2.shtml for marine impacts. See the latest NHC Forecast/Advisory and Public Advisory on Zeta at www.hurricanes.gov for more details. ...TROPICAL WAVES... A tropical wave extends along 51/52W from 05N-17N, moving W at 15-20 kt. Scattered moderate convection is seen within 60 nm W of the wave axis and within 240 nm E of the wave axis north of 08N. Strong winds are occurring behind the wave axis north of 11N. The tropical wave will spread enhanced rainfall and gusty winds across the Lesser Antilles late Wed through Thu. A Caribbean Sea tropical wave extends along 66/67W from 20N over Puerto Rico to the N coast of Venezuela, moving W at 15 kt. Scattered moderate convection is occurring within 60 nm W and 120 nm E of the wave axis, mainly north of 15N, including over the waters near Puerto Rico. Scattered showers and isolated tstorms extending from Montserrat to Anguilla, including near St. Kitts and Nevis, are being produced by an upper-level trough that is nearly stationary over the area. The wave will slow down this afternoon over the Mona Passage then reach the Dominican Republic tonight. The wave will increase the likelihood of showers and tstorms across the Greater Antilles. ...MONSOON TROUGH/ITCZ... The monsoon trough axis extends from the coast of Sierra Leone near 07N12W to 05N19W. The ITCZ continues from 05N19W to 04N38W to 08N49W. Aside from the convection mentioned in the tropical waves section, scattered moderate convection is from 02N-10N between 08W-17W and from 06N-11N between 39W-47W. GULF OF MEXICO... Tropical Storm Zeta is currently affecting the south-central Gulf of Mexico, south of 26.5N between 84W-94W. Zeta was producing seas to 20 ft this morning near the center. Expect seas of 20 to 30 ft tonight over the central Gulf of Mexico along with winds of 50 to 75 knots as Zeta restrengthens into a hurricane. Similar conditions are expected over the north-central Gulf of Mexico on Wednesday as Zeta approaches the coast of SE Louisiana. Hurricane conditions and life-threatening storm surge are expected along portions of the northern Gulf Coast by late Wed, and Storm Surge and Hurricane Warnings are in effect. Residents in the warning areas should follow any advice given by local officials. Please see the special features section above for more details on Zeta. As of 27/1500 UTC, a cold front extends from Galveston Texas to 26N97W to NE Mexico near 24N98W and inland across northern Mexico. The latest ASCAT pass shows moderate wind speeds prevail over the SW Gulf south of 25N and west of 94W. The front will become stationary through tonight. Another cold front will move into the NW Gulf Wed and stretch from Florida to the Yucatan Peninsula by late Thu. It will reach to near western Cuba Fri night. Fresh to locally strong northerly winds will follow behind the front through Fri night. CARIBBEAN SEA... Tropical Storm Zeta is centered over the south-central Gulf of Mexico. A large band of scattered strong convection still persists from the Yucatan Channel to NE Nicaragua, or inside a box from 22N88W to 12N85W to 13N82W to 23N83W to 22N88W. Heavy rainfall could lead to flash flooding in urban areas today in the Yucatan Peninsula and western Cuba. These squalls will gradually lift northward to over the eastern and central Gulf of Mexico through Wed. SE winds of 20 to 30 kt are occurring north of 20N and west of 83.5W, including over the Yucatan Channel, according to the a recent ASCAT pass. Seas are still 8 to 12 ft in the Yucatan Channel. Expect winds and seas to gradually diminish through early Wed over the NW Caribbean and Yucatan Channel as Zeta pulls farther away from the Caribbean basin. See the special features section above for more details on Zeta. Away from the direct influence of Zeta, fresh trade winds are noted across much of the remainder of the basin per a recent ASCAT pass, with the exception of mainly light to gentle winds over the far SW Caribbean offshore of Panama and Costa Rica. An upper-level trough axis extends from the central Atlantic near 30N54W to 20N59W to 09N69W over northern Venezuela. The upper trough is enhancing scattered showers across portions of the Lesser Antilles. The tropical wave near 67W will move across the central Caribbean Thu and the western Caribbean Fri. See the tropical waves section above for more details. ATLANTIC OCEAN... The Atlantic forecast waters are under the influence of a 1029 mb high pressure centered southwest of the Azores near 32N36W. The weak surface trough from 30N73W to 25N75W is no longer producing any showers or tstorms. An upper-level trough axis extends from the central Atlantic near 30N54W to 20N59W to 09N69W. Scattered moderate convection is from 17N-23N between 52W-59W. Fresh to strong easterly winds prevail across the Atlantic from 10N-27N between 30W-55W. Fresh to strong NE winds are from 17N-27N between 30W and the coast of Africa. Moderate to fresh SE winds will persist south of 26N and west of 70W through Thu. A cold front will move over the waters to the east of northern Florida on Fri, with some strong SW winds ahead of it. The front will reach from near 29N65W to the central Bahamas by late Sat. Fresh to strong northeast to east winds will follow this front, mainly north of about 28N, through the weekend. A combination of northerly and easterly swell generated from a tropical wave Wed will maintain relatively high seas north and east of Puerto Rico and the Leeward Islands into Thu. $$ Hagen