000 AXNT20 KNHC 170459 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 0605 UTC Sun Oct 17 2021 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 31N. The following information is based on satellite imagery, weather observations, radar and meteorological analysis. Based on 0000 UTC surface analysis and satellite imagery through 0455 UTC. ...SPECIAL FEATURES... Gulf of Mexico Gale Warning: A cold front extends from near the Big Bend region of Florida to southern Veracruz, Mexico. NW to N winds are funneling along the coast of Mexico near Tampico and reaching gale force. Recent scatterometer satellite data depict fresh to strong N to NE winds elsewhere north of the front. Seas of 8-12 ft are found behind the front in the NW and W Gulf. Latest altimeter wave heights indicate seas up to 12 ft off SE Tamaulipas. Converging winds in the SW Gulf are causing an area of showers and isolated thunderstorms, mainly S of 24N and W of 94W. Increasing winds and building seas will spread southward, extending off the coast of Veracruz, Mexico on Sun. Seas will peak near 15 ft off Veracruz, Mexico by Sun afternoon. Please read the latest High Seas Forecast issued by the National Hurricane Center at website https://www.nhc.noaa.gov/text/MIAHSFAT2.shtml for more details on both warnings. ...TROPICAL WAVES... The axis of a tropical wave is along 39W, south of 20N, and it is moving W at 10-15 kt. Scattered moderate convection is observed from 02N to 09N and between 35W and 41W. No deep convection noted N of 09N due to dry air. The axis of a tropical wave is along 52W, south of 20N, and it is moving W at around 15 kt. Only a couple of showers are seen near the wave axis. The axis of a tropical wave is along 72W, south of 20N, and it is moving W at around 15 kt. No deep convection is occurring near the wave over the Caribbean Sea. However, it is likely enhancing the isolated showers and thunderstorms occurring in Hispaniola and E Venezuela and N Colombia. The axis of a tropical wave is along 85W, south of 17N, extending from the Gulf of Honduras, across E Honduras, Nicaragua and W Costa Rica, and into the E Pacific. The wave is moving W at 10-15 kt. Scattered moderate convection is noted within 200 nm on both sides of the wave axis. ...MONSOON TROUGH/ITCZ... The monsoon trough extends from the border of Senegal and Mauritania near 16N17W to 09N19W. The ITCZ continues from 09N19W to 06N29W to 08N38W. It resumes from 08N39W to 07N51W and then from 07N53W to the coast of Guyana near 08N59W. Aside from convection mentioned in the Tropical Waves section, scattered moderate to isolated strong convection is noted from 01N to 09N and between 15W and 35W GULF OF MEXICO... Refer to the Special Features for information on the Gale Warning in effect for the SW Gulf of Mexico. The main feature of interest in the Gulf of Mexico is the aforementioned cold front draped across the region that aside from the impacts described in the Special Features section is producing a few showers near the frontal boundary in the NE and central portions of the basin. A few showers are also found near the western coast of Yucatan, but this activity is expected to wave as it moves further into the E Bay of Campeche. The rest of the region enjoys fairly tranquil weather conditions. Moderate or weaker and seas of 1-3 ft prevail ahead of the frontal boundary. For the forecast, gale-force N winds are expected to develop off of Veracruz, Mexico early Sun through late afternoon. Winds will gradually veer from the E Mon through Tue as the front becomes aligned W to E along 23N and dissipates. CARIBBEAN SEA... Please refer to the section above for details on the tropical waves moving across the basin. An upper level trough continues to dwell from the NW Bahamas through the Gulf of Honduras. Divergence aloft over the central and SW Caribbean results widely scattered showers, while the rest of the region enjoys tranquil weather conditions. A weak pressure gradient allows for moderate or weaker trades. Seas of 2-4 ft prevail E of 75W and 1-2 ft elsewhere. For the forecast, a weak pressure gradient across the Caribbean basin will lead to tranquil marine conditions through early Mon. A cold front will enter the NW Atlc over the weekend and move SE. High pres building in the wake of the front will bring a return to moderate trade winds to the Caribbean Mon night through Tue and then moderate to fresh winds late Wed. ATLANTIC OCEAN... A cold front extends from a strong low pressure near the Azores, entering the tropical Atlantic near 31N37W and extending to 25N48W, then a trough extends from 25N48W to 20N67W. Also, a weak trough extends from 23N51W to 18N55W. Scattered moderate to isolated strong convection extends within 250 nm to the E of the frontal boundary and trough axis between 37W and 57W. Scatterometer satellite data indicate that fresh to strong SW-W winds are occurring in the region of the convection. Seas of 8-12 ft are present N of 23N and between 33W and 50W. The rest of the tropical Atlantic enjoys fairly tranquil weather conditions, moderate or weaker winds and seas of 4-7 ft. The Cumbre Vieja volcano, on the island of La Palma in the Canary Islands, has been erupting since 19 September 2021. Low ash concentrations moving NW. Marine and aviation interests should monitor this ongoing situation by reading the Volcanic Ash Advisory issued by Meteo-France at http://vaac.meteo.fr/volcanoes/la-palma/ For the forecast west of 65W, a weak pres pattern prevails across the W Atlc to the SW of Bermuda. A cold front will move off the SE U.S. coast tonight and continue southeastward across all of Florida by Sun night, reaching from Bermuda to the Straits of Florida by Mon morning. Expect fresh to strong N to NE winds behind the front through Mon morning. High pres will shift ESE across the W Atlc along 31N-32N Tue through Wed. $$ DELGADO