000 AXNT20 KNHC 300555 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 0605 UTC Tue Nov 30 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 0545 UTC. ...MONSOON TROUGH/ITCZ... The monsoon trough axis extends from the coastal border of Guinea and Sierra Leone near 09.5N13W and continues to 06N18W, where latest scatterometer data indicates that it transitions to the ITCZ to 03N24W to 03N30W and to 02N41W. Scattered moderate convection is within 180 nm north of the ITCZ between 30W-39W. GULF OF MEXICO... A weakening cold front is southeast of the Gulf over central Cuba. A trough extends from central Cuba to across the central Yucatan Peninsula and to southeastern Mexico. High pressure is building across the Gulf of Mexico resulting in fairly tranquil weather conditions, except for small patches of broken to overcast low and mid-level clouds, with possible light rain and drizzle that are observed over some areas of the SW Gulf and south-central Gulf waters. Recent scatterometer satellite data and surface observations show gentle to moderate northeast to east winds across the Gulf, with the exception of the southeastern Gulf and Straits of Florida were fresh northeast winds are noted. Seas are in the range of 4-6 ft, except for lower seas of 2-4 ft in the NE Gulf and north-central Gulf waters and 5-7 ft in the SW Gulf. For the forecast, high pressure is building across the northern Gulf and will dominate the basin the remainder of the week. As high pressure moves eastward, southerly return flow will set-up across the northwest Gulf by mid-week. Looking ahead, a weak cold front may enter the northern Gulf by late Sat. CARIBBEAN SEA... Convergence of northeast trade winds along with divergent flow aloft east of a weak mid/upper level trough over Nicaragua are combining to support a large area of showers and thunderstorms, south of 14N between to some of the coastal sections of Nicaragua, Costa Rica and Panama. Satellite-derived winds and surface observations indicate fresh to strong trades in the south-central and SW Caribbean Sea. Seas of 4-6 ft are within this part of the sea. The earlier cold front that entered the northwestern Carribbean Sea from the Gulf of Mexico is presently weakening from central Cuba to 21N84W, where it becomes a trough to inland the Yucatan Peninsula to just south of Cozumel. Broken to overcast low and mid-level clouds with possible scattered showers are along and within 60-90 nm northwest of the front/trough. Elsewhere, fairly tranquil weather conditions, moderate or weaker trades and seas of 2-4 ft are prevalent. For the forecast, moderate to fresh northeast to east winds will persist across the Caribbean through Wed, with strong winds pulsing off Colombia, mainly at night. High pressure building north of the area will slightly enhance trade winds across the Caribbean later in the week. Meanwhile, moderate north to northeast swell will continue across the Atlantic waters east of 70W and through the northeast Caribbean passages through tonight. ATLANTIC OCEAN... As of 03Z, a cold front extends from 31N65W through the central Bahamas and to central Cuba, where it begins to weaken into the northwestern Caribbean Sea. A pre-frontal trough extends from near 28N67W to 20N72W. Scattered moderate to isolated strong convection is noted north of 29N between 58W-62W and within 60 nm of 27N61W. The latest ASCAT data shows strong southwest winds within 180 nm east of the front north of 28N, and fresh to strong south to southwest winds elsewhere within east of front to 58W and north of 26N. The ASCAT data also depicts fresh to strong northwest winds within about 60 nm west of the front and north of 29N. Seas of 8 ft are present within the area of strong winds. Over the Central Atlantic, a trough extends from near 29N41W to 22N44W. Clusters of scattered moderate convection are seen north of 24N between the trough and 37W. This activity is being supported by a broad upper-level trough located over that part of the area. A strong 1037 mb high pressure center near the Azores and lower pressures over western Africa allow for a moderate pressure gradient, resulting in a large area of fresh to strong anticyclonic winds east of 40W and north of 05N. The strongest winds are occurring east of 30W and north of 14N, including the waters surrounding the Canary Islands. Seas of 8-12 ft are present east of 45W, with the highest seas occurring north of the Cabo Verde Islands. Elsewhere, fairly tranquil weather conditions, moderate or weaker winds and seas of 5-8 ft prevail. The Cumbre Vieja volcano, on the island of La Palma in the Canary Islands, has been erupting since 19 September 2021. 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 previously-mentioned cold front will move quickly southeast across the forecast waters, and reach from near 27N65W to eastern Cuba by Tue morning. High pressure will settle across the forecast area in the wake of the front, and dominate the region through Sat. $$ Aguirre