609 AXNT20 KNHC 081035 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1205 UTC Wed Mar 8 2023 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... Atlantic Ocean Gale Warning and Swell Event: As of 08/0900 UTC, a cold front extends from 31N58W to 27N69W to 30N81W. Gale force winds are currently occurring on both sides of the front, mainly north of 28N between 52W and 67W. Seas are currently 15 to 19 ft in the gale force wind area. The front is progressing quickly southeastward and will extend from 31N46W to 26N55W to 23N70W to Miami, FL by this evening, and then from 31N43W to 23N55W to the N coast of Hispaniola to Havana, Cuba Thu morning. Gale force winds are expected to continue through Thu evening, especially ahead of the front. This prolonged event will build seas in the basin already impacted by elevated swell from previous storms, creating some of the highest sea states in the subtropical Atlantic this year. Seas will build to 19 to 21 ft later this morning while propagating south and east. Seas in excess of 12 ft will reach as far south as 21N on Thu. By late Thu, the vast majority of the west and central Atlantic east of the Bahamas and north of 17N will be impacted by rough seas in excess of 8 ft while very rough to high seas persist in the subtropical central Atlantic. The swell from this event will slowly subside during the weekend, although the next significant low-pressure system will partially rebuild swell in the western Atlantic over the weekend, discussed below in the Atlantic Ocean section. Please read the latest High Seas Forecast at https://www.nhc.noaa.gov/text/MIAHSFAT2.shtml for more details on the gale and swell events. ...MONSOON TROUGH/ITCZ... The monsoon trough extends from the coastal border of Liberia and Sierra Leone near 07N11W to 03N18W. The ITCZ continues from 03N18W to 00N34W to 02S44W. Scattered moderate and isolated strong convection is observed from 05S to 04N between 13W and 43W. GULF OF MEXICO... High pressure prevails across the Gulf of Mexico, anchored by a 1020 mb high centered near 27N87W. Gentle winds and 1-2 ft seas prevail from the NE Gulf to the central Gulf. Moderate to locally fresh E winds and seas 3-4 ft are noted to the west of the Yucatan Peninsula, over the eastern Bay of Campeche and south-central Gulf. Gentle to moderate SE winds and 2 to 3 ft seas are occurring over the NW and west-central Gulf. For the forecast, weak high pressure centered over the NE Gulf will dominate the area through today. A cold front will enter the NE Gulf today, and extend from Havana, Cuba to near Mobile, Alabama by Thu afternoon, before dissipating by late Thu night. Moderate to fresh SE winds are forecast in the far E Gulf, east of the front. Another weak cold front is likely to reach the northern Gulf Coast Fri and move over the northern Gulf waters by Fri night before dissipating Sat. CARIBBEAN SEA... Fresh NE trades prevail over the south central Caribbean, in the Colombian basin, south of 14N between 74W and 81W, where seas are 5 to 7 ft. Gentle to moderate winds are noted elsewhere, with seas 2-4 ft. For the forecast, gentle to locally moderate winds will prevail across most of the basin today due to a weak pressure gradient as an Atlantic cold front sinks southward toward the Caribbean islands. The cold front is forecast to reach the Greater Antilles on Thu, then reach from the Leeward Islands to Jamaica to the western tip of Cuba early Fri before dissipating Fri night. The front will bring large N swell through the NE Caribbean passages and Tropical N Atlantic waters beginning Thu and lasting into the weekend. Also, fresh N to NE winds are expected behind the front over the far N Caribbean Thu night. ATLANTIC OCEAN... Please read the Special Features section for details on a gale warning and associated high seas across the Atlantic forecast waters this week. In the eastern Atlantic, a weak stationary front extends from 31N30W to 27N37W, dissipating to 25N45W. Scattered showers are within 60 nm of the front N of 29N and E of 32W. Fresh winds and rough seas are noted on both sides of the front, and an earlier altimeter pass found 12-15 ft swell in the central Atlantic north of 27N. Otherwise, a high-pressure ridge extends from the Canary Islands to the Leeward Islands to the Old Bahama Channel. Winds are light to gentle near the ridge axis. Swell in excess of 6 ft prevails across the basin east of a line from 31N80.5W to 21N65W to 12N46W to 08N59W to 06N53W. West of that line, seas are 4 to 6 ft. For the forecast W of 55W, gale force winds will continue on either side of the west Atlantic cold front today, mainly N of 28N and E of 67W. Winds are forecast to diminish below gale force west of 55W by late this afternoon, but strong NW winds will persist N of 27N and E of 65W through Fri. A significant NW to N swell event will follow the front, with seas of 12 to 21 ft covering most of the waters N of 25N and E of 74W by early this afternoon. Seas of 12 ft will reach as far south as 21N Thu. Looking ahead, the next cold front is forecast to move off the southeast U.S. coast by Fri afternoon, brining strong to near gale force winds to waters east of Florida. This system will move eastward across the area during the weekend, with gale force winds possibly developing N of 29N and E of 70W. Expect very large seas over the west-central Atlantic north of 26N with this system by Sun. $$ Hagen