000 AXNT20 KNHC 150543 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 0605 UTC Wed Mar 15 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 0000 UTC surface analysis and satellite imagery through 0500 UTC. ...SPECIAL FEATURES... Atlantic Gale Warning: A cold front extending from SE of Bermuda to across the Central Bahamas to western Cuba will continue moving SE, reaching from 31N59W to central Cuba this morning, from near 29N55W to the Windward Passage Thu morning, and from 20N55W through the Leeward Islands by Fri morning. Strong to gale- force northerly winds immediately behind the front will move through the Central and SE Bahamas tonight, and then shift across the SE waters and into the Caribbean Islands Thu and Thu night. Large N swell will accompany this front, with seas of 12 ft or greater N of 23N and E of 73W. Atlantic Significant Swell Event: Large NW swell, with significant wave heights of 12 to 15 ft based on altimeter data, is occurring N of 23N between 35W and 50W. This swell event is generated by a frontal boundary sweeping through the region, with the cold front currently extending from 31N32W to 26N38W. A stationary front continues from 26N38W to 21N50W to 23N60W. Mainly moderate winds are on both sides of the front, generally north of 28N between 30W and 45W. Seas are forecast to subside below 12 ft across the forecast waters by this morning. Please read the latest High Seas Forecast at https://www.nhc.noaa.gov/text/MIAHSFAT2.shtml for more details on these events. ...MONSOON TROUGH/ITCZ... The monsoon trough enters the Atlantic through the coast of Africa near 09N13W then continues SW to near 04N20W. The ITCZ extends from 04N20W to 01N30W to 00N50W. Scattered moderate isolated strong convection is noted from 02N to 05N between 18W and 28W. Similar convection is also seen from 00N to 03N between 42W and 51W. GULF OF MEXICO... A stationary front extends across the basin from western Cuba to near Poza, Rica Mexico. High pressure dominates the remainder of the Gulf waters N of the front and the State of Florida. Numerous showers and thunderstorms are occurring along the front, mainly from 21N to 24N between 87W and 93W, and in the Yucatan Peninsula where a surface trough is analyzed. Gusty winds to gale force may occur in association with this strong convective activity. A mid- level trough is helping to induce this convection. N of the front, fresh to strong NE winds are noted with seas of 8 to 11 ft over the western Gulf based on altimeter data, and 4 to 7 ft over the eastern Gulf per buoys observations. A recent scatterometer pass provided observations of fresh to strong northerly winds to the NW of the Yucatan Peninsula extending southward across the eastern Bay of Campeche. Elsewhere south of the front, light to gentle winds, and seas of 3-5 ft are noted. For the forecast, the stationary front will be reinforced with a surge of fresh to strong NE winds, pushing the front SE of the basin today. Return flow will develop across the W Gulf by tonight become fresh to strong Thu and spread to the entire Gulf Thu night, ahead of the next cold front. This next front will move into the NW Gulf Fri morning, reaching from Apalachee Bay, Florida to the central Bay of Campeche Sat morning. Gale-force N winds are briefly possible behind the front offshore the upper Mexican waters late Fri afternoon, shifting to offshore Veracruz Fri evening and night. CARIBBEAN SEA... A relatively weak pressure gradient prevails across the basin with a ridge from the Atlantic reaching the NE Caribbean. This is resulting in light to gentle winds over the NE Caribbean, including Puerto Rico and regional waters. Fresh to locally strong trades are within about 120 nm of the coast of Colombia. Gentle to moderate wind prevail elsewhere, except in the lee of Cuba where light and variable winds are observed. Seas are in the 4 to 6 ft range in the south-central Caribbean, and 2 to 4 ft elsewhere. A cold front has reached western Cuba, producing scattered showers and thunderstorms. Similar convective activity is noted near the Honduras/Nicaragua border. Elsewhere, patches of low level moisture, with isolated to scattered passing showers are seen, more concentrated over the Greater Antilles. For the forecast, a weak pressure pattern is yielding below normal tradewinds across most of the basin. However winds will increase slightly through Wed, with fresh winds pulsing to strong winds at night in the south-central and southeast portions. Moderate northerly swell moving through the Atlantic waters and NE Caribbean Passages will gradually subside through Thu morning. A cold front is forecast to sink S-SE across the northwestern basin Wed and Wed night, reach from the Windward Passage to Belize on Thu, and then from the northern Leeward Islands to the central Caribbean along 16N Fri. Strong winds will follow the front, locally higher in Atlantic passages, with large N swell spreading through Atlantic passages early Fri through Sat. Another front may stall near or just N of the Yucatan Channel for the end of the upcoming weekend. ATLANTIC OCEAN... A cold front extends from SE of Bermuda to across the Central Bahamas to western Cuba. Currently, seas of 8 to 10 ft are noted per altimeter data behind the front and E of the Bahamas. Moderate to fresh N winds are N of 27N between 77W and the E coast of Florida. Gale force winds are expected to develop behind this front by tonight into Thu morning. Please, see the Special Features section above for more details. A second cold front stretches from 31N32W to 26N38W where it becomes stationary to 26N38W to 21N50W to 23N60W. A swell event, with seas in excess of 12 ft, follows the front. Please, see the Special Features section above for more information. A 1021 mb high pressure is located between the fronts near 27N48W. Another high pressure center of 1023 mb is NE of the Madeira Islands. Fresh to strong NE winds and seas of 7 to 8 ft are noted between the coast of Western Saharan and the Canary Islands. Mainly moderate trades are blowing across the tropical Atlantic with seas of 5 to 7 ft. For the forecast W of 55W, a cold front extending from SE of Bermuda to across the Central Bahamas to the Straits of Florida will continue moving SE, reaching from 31N59W to central Cuba this morning. Please, see the Special Features section above for more information. Yet another cold front is expected to move off Florida this weekend, with fresh to strong southerly winds ahead of it Fri night through Sat. That front is expected to reach from 31N70W to S Florida before stalling. $$ GR