000 AXNT20 KNHC 131711 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1805 UTC Sat Mar 13 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 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. ...MONSOON TROUGH/ITCZ... The monsoon trough extends from the coast of Guinea-Bissau near 12N16W to 03N24W. The ITCZ continues from 03N24W to 02N43W. Scattered moderate and isolated strong convection is seen from 02S-06N between 02W-17W. Isolated moderate convection is from 01N-04N between 17W-30W and from 02N-06N between 41W-50W. GULF OF MEXICO... A 1026 mb high is over the northern Florida peninsula. Surface ridging extends westward across the northern Gulf. As a result, the latest ASCAT data pass shows gentle wind speeds over the NE and north-central Gulf, north of 27N and east of 91W, where seas are estimated to be 2-4 ft. Fresh SE return flow is over the western Gulf, with seas of 4-6 ft. Mid and upper-level anticyclonic flow prevails across the basin, leading to subsidence and relatively dry air. A few patchy areas of marine fog are noted near the Texas coast and Alabama coast. For the forecast, southeast return flow over the western Gulf will slowly expand across the rest of the basin this weekend, becoming fresh to locally strong in the NW Gulf tonight. Winds will diminish into early next week as a cold front stalls near the coast of Texas Sun through Mon night. Patchy areas of dense marine fog are possible along portions of the Gulf Coast during the next few nights and mornings. CARIBBEAN SEA... A ridge of high pressure is centered over the western Atlantic. The latest ASCAT data pass shows fresh to locally strong winds just off the coast of Colombia, in the Windward Passage and in the lee of Cuba. Moderate to fresh NE winds prevail elsewhere across the NW Caribbean. Gentle trade winds prevail east of 70W. Seas are in the 5-7 ft range over the western half of the Caribbean, except to 8 ft off the coast of Colombia. Seas range from 4 to 5 ft over the eastern Caribbean. A mid-level ridge prevails over the western portion of the basin, with subsidence and relatively dry air. Some cloudiness and rain showers are noted from the southern Windward Islands extending westward to the ABC Islands. For the forecast, winds and seas will diminish across the region through Sun as the high pressure north of the Caribbean Sea weakens. Pulses of fresh to strong winds will persist in the Windward Passage and south of Hispaniola into early next week. Fresh to strong NE winds are expected near the coast of Colombia at night through Wed night. ATLANTIC OCEAN... A ridge of high pressure is across the west-central Atlantic from a 1023 mb high near 30N55W to a 1026 mb high pressure over the northern Florida peninsula. The latest ASCAT pass indicates that a surface trough extends NE of Puerto Rico from 24N61W to 20N64W. Fresh NE winds are located within 180 nm to the north and northwest of the trough axis. Gentle anticyclonic winds are from 26.5N-31N along the ridge axis. Moderate NE winds cover the area of the Bahamas. Scattered showers and isolated tstorms extend NE from the northern portion of the aforementioned surface trough from 21N-27N between 56W-64W. Farther east, a cold front extends from 32N36W to 29N38W, then continues as a dissipating cold front to 25N47W. The boundary continues as a shear line from 25N47W to 23N61W. Fresh winds are on either side of the cold front north of 29N between 32W-42W. Strong NE winds are noted off the coast of Morocco north of 30N and east of 13W. Gentle to moderate trades prevail across the tropical Atlantic waters between Africa and the Lesser Antilles. Seas are 5-7 ft across most of the Atlantic, except 7-9 ft to the north of Puerto Rico and Hispaniola. For the forecast, winds and seas will diminish across the western Atlantic, south of 26N, through Sun as high pressure in the west- central Atlantic weakens. The surface trough north of Puerto Rico will drift eastward during the next couple days. A cold front will move southward between Bermuda and northern Florida tonight and Sun. A stronger, reinforcing cold front will move south of 30N on Mon. This system will bring strong to near gale force winds north of 27N, progressing from west to east Mon into Tue between 40W-70W. Gale force winds are possible north of 30N over the central Atlantic, to the east of Bermuda. Seas of 15 to 25 ft will follow the front. $$ Hagen