000 AXNT20 KNHC 271002 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1205 UTC Wed Oct 27 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 0600 UTC surface analysis and satellite imagery through 1000 UTC. ...SPECIAL FEATURES... Gulf of Mexico Gale Warning: Strong to near gale force winds will follow a cold front expected to move through the Gulf of Mexico today through Thu night. Water temperatures are still relatively warm over the Gulf of Mexico. The cooler air following the front will move over the warmer waters and allow gale force winds in the lower levels of the atmosphere to mix to the surface over the north-central and northeast Gulf. Therefore a gale warning for frequent gusts to gale force has been issued for these area valid from late Wed night through Fri. Seas will build as high as 14 ft in the wake of the front over the northern Gulf. A band of showers and thunderstorms will be associated with the front. ...TROPICAL WAVES... An Atlantic tropical wave is along 30W/31W from 18N southward, moving W at 10-15 kt. Scattered moderate to isolated strong convection is noted where the wave meets the ITCZ. A recent ship observation showing NE winds between Colombia and Jamaica indicated there may be a surface trough along 74W/75W, but extending no farther north than 15N/16N due to the presence of a ridge across the Greater Antilles. This feature will move little over the next couple of days, and gradually become absorbed into a broader area of low pressure centered over the southwest Caribbean. ...MONSOON TROUGH/ITCZ... The monsoon trough extends off the coast of Senegal near 14N17W to 11N28W. The ITCZ extends from 07N35W to the coast of French Guiana. In addition to the convection described in the Tropical Waves section, scattered moderate to isolated strong convection is occurring from 04N to 09N between 17W and 41W. GULF OF MEXICO... A stationary front extends from west central Florida near Ft. Myers to SE Louisiana. A few showers are near the frontal boundary. The front is forecast to lift northward while dissipating. Light to gentle winds are noted over the eastern Gulf. Southerly return flow is on the increase over the western Gulf ahead of a cold front forecast to enter the Gulf region later this morning. Recent scatterometer data provided observations of mainly fresh SE-S winds N of 21N and W of 96W. Seas are in the 3-5 ft range in association with these winds. Seas of 1-3 ft prevail elsewhere across the Gulf waters. For the forecast, a cold front is expected to push off the Texas coast later this morning. The front will move across the Gulf region through Thu night. Frequent gusts to gale force and building seas will accompany the front. Please, see the Special Features section for more details. CARIBBEAN SEA... The Atlantic ridge extends across the Greater Antilles, with a weak 1014 mb high pressure located over the Cayman Islands. The ridge was displaced southward ahead of a deep layer trough and associated cold front currently north of the region moving through the Bahamas. Recent scatterometer data show fresh to strong winds over the south-central Caribbean, particularly from 11N-13N between 68W-75W, including the Gulf of Venezuela. Moderate to fresh E winds are over the Gulf of Honduras. Gentle to moderate E to SE winds are noted elsewhere. Seas are 4 to 6 ft in most areas. For the forecast, the position of the surface ridge will continue to support moderate to fresh trades across the south-central Caribbean, including the Gulf of Venezuela through early Thu. Gentle to moderate SE to S winds will prevail over the NW Caribbean through Thu night ahead of a cold front forecast to reach western Cuba and the NW Caribbean. The front will extend from western Cuba to the Gulf of Honduras by midday Fri, and from central Cuba to NE Honduras on Sat, then stall on Sun from eastern Cuba to near Cabo Gracias a Dios, Nicaragua while dissipating. ATLANTIC OCEAN... A recent scatterometer pass showed fresh to strong W to NW winds ahead and behind a cold front that extends from 31N70W to south- central Florida. This front follows a frontal trough that stretches from near Bermuda to the SE Bahamas. Scattered showers, with embedded thunderstorms are noted ahead of the trough axis while a narrow band of mainly low clouds and possible showers is associated with the front. The remainder of the Atlantic forecast waters is under the influence of a ridge anchored by a 1022 mb located near the Azores. Seas are 6 to 9 ft in the area of fresh to strong winds north of 29N between 60W and 78W, and 4 to 6 ft elsewhere over open waters. A belt of moderate to fresh winds are noted south of the ridge, except for fresh to locally strong NE winds near the coasts of Morocco and Mauritania. The Cumbre Vieja volcano, on the island of La Palma in the Canary Islands, has been erupting since 19 September 2021. Ash cloud slowly drifting SW. Medium to high concentration of volcanic ash in the vicinity of the volcano. 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, the cold front extending from 31N70W to south-central Florida will reach from 31N67W to the Straits of Florida today, and from 31N65W to the central Bahamas by tonight. The front will dissipate over the SE waters on Thu. The next cold front is expected to sweep across the region Thu night through Fri night, then stall from 31N68W to eastern Cuba during the upcoming weekend. Fresh to strong winds and building seas are expected on either side of these fronts. $$ GR