000 AXNT20 KNHC 181226 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1205 UTC Sat Mar 18 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 1030 UTC. ...SPECIAL FEATURES... Atlantic Significant Swell Event: A cold front extends southwestward from near the Azores across 31N40W to near Guadeloupe in the Leeward Islands. Large, long-period NW swell behind this front is causing 12 to 15 ft seas north of 25N between 41W and 55W. This swell will continue to propagate eastward while gradually diminish through tonight, allowing seas to subside below 12 ft by Sun morning as the front moves E of 35W. Gulf of Mexico Gale Warning: A strong cold front extends from the Florida Big Bend area to near Veracruz, Mexico. This front will reach from near Fort Myers, Florida to the eastern Bay of Campeche late this afternoon, spreading strong to near-gale force northerly winds to the north-central, northeastern and central Gulf. Frequent gusts to gale force are expected at the central Gulf by late this afternoon, which will expand into the eastern Bay of Campeche by Sun evening. In addition, winds offshore Veracruz, Mexico will also reach gale force by Sun morning. Seas will peak between 11 and 14 ft under the strongest winds. Winds and seas will gradually diminish Sun night through Mon as the front stalls and dissipates over the far northwest Caribbean. Please read the latest High Seas Forecast at https://www.nhc.noaa.gov/text/MIAHSFAT2.shtml and Offshore Waters Forecast at https://www.nhc.noaa.gov/marine/offshores.php for more details on the Gale Warning and Significant Swell above. Atlantic Gale Warning east of the Canary Islands: Strong pressure gradient exists between a 1024 mb high north of the Madeira Islands and lower pressures over northern Africa. This will produce gale force winds in the Meteo-France forecast regions of Agadir Sat morning through Sat evening and Tarfaya late Sat afternoon into Sat night. Please read the Meteo-France High Seas Forecast and Warning listed on the WMO website at https://wwmiws.wmo.int/index.php/metareas/dispaly/2 for more details. ...MONSOON TROUGH/ITCZ... A monsoon trough enters the Atlantic along the African coast near the Sierra Leone-Liberia border, and extends west-southwestward to 03N21W. Scattered moderate convection is seen near the monsoon trough from 02N to 06N between 10W and 20W. An ITCZ continues westward from 03N21W across 02N35W to the Amazon River Delta, Brazil. Patchy showers are noted up to 100 nm along either side of the ITCZ. ...GULF OF MEXICO... Please read the Special Features section for more information about an upcoming Gale Warning late this afternoon. A strong cold front extends from the Florida Big Bend area to near Veracruz, Mexico. Numerous heavy showers and scattered thunderstorms are occurring near and up to 100 nm southeast of the front north of 25N, while scattered showers and isolated thunderstorms are found near and up to 80 nm northwest of the front south of 25N. A diurnal surface trough is triggering scattered showers and thunderstorms at the central Bay of Campeche. Fresh to strong with locally near-gale northerly winds are present behind the front from the western Bay of Campeche northeastward to near New Orleans. Seas are at 6 to 9 ft across the northwestern and north-central Gulf, and 9 to 11 ft for the west-central Gulf and western Bay of Campeche. Moderate to fresh southerly winds are present east of the front for the rest of the Gulf. Seas range from 6 to 9 ft at the central Bay of Campeche, and 4 to 6 ft elsewhere in the Gulf. For the forecast, the cold front will reach from near Fort Myers, Florida to the eastern Bay of Campeche late this afternoon, spreading strong to near-gale northerly winds to the north-central and central Gulf, outside the Gale Warning area. This front should reach from the Florida Straits to Yucatan Peninsula Sun afternoon, bringing fresh to strong northerly winds to the western portions of the east-central and southeastern Gulf. Looking ahead, winds and seas will gradually diminish across the Gulf during the early to middle parts of next week as the front stalls and dissipates over the far northwest Caribbean. ...CARIBBEAN SEA... A cold front curves west-southwestward from the central Atlantic across Guadeloupe in the Leeward Islands to south of the Dominican Republic near 16N69W. Patchy showers are noted up to 60 nm along either side of this front. Convergent southerly winds are generating scattered showers and isolated thunderstorms south of Cuba, including waters near the Cayman Islands and Jamaica. Fresh with locally strong NE to ENE winds and seas of 6 to 8 ft are evident across the eastern and central basin, including the Windward and Mona Passages, and north of Colombia. Gentle to moderate with locally fresh E to SE winds and seas at 4 to 6 ft prevail for the rest of the basin. For the forecast, high pressure north of the area behind the front will support fresh to occasionally strong NE to E winds and moderate to occasionally rough seas across the eastern and central Caribbean through Mon morning. Large northerly swell will persist at the Atlantic passages through tonight. Fresh to strong easterly winds will continue to pulse off Colombia through Mon, then increase to between strong and near-gale by Tue. Winds and seas are expected to increase in the Yucatan Channel by Sun night as a cold front moves into the area. These winds and seas should gradually diminish through Tue as the stalled front dissipates. ...ATLANTIC OCEAN... Please read the Special Features section at the beginning about significant swell in the central Atlantic, and gales east of the Canary Islands. A cold front extends southwestward from near the Azores across 31N40W to near Guadeloupe in the Leeward Islands. Scattered showers are occurring near and up to 120 nm northwest of this feature. Fresh to strong westerly winds are noted behind this front north of 28N between 40W and 52W. Refer to the Special Features section for sea heights in this area. Farther southwest, fresh to strong NE to ENE winds with 8 to 11 ft seas are seen from the front northward to 20N between 50W and the Leeward Islands/Dominican Republic. To the north, a 1021 mb high near 29N67W is promoting light to gentle winds from the southeast Bahamas northward to 29N between 52W and the central Florida coast. Within this area, moderate northerly swell are sustaining 8 to 11 ft seas east of 64W, and 4 to 7 ft seas west of 64W. Off the northeast Florida coast, fresh to strong southerly winds with 7 to 10 ft seas in easterly swell exist north of 29N between 70W and the Georgia/northeast Florida coast. Near the Canary Islands outside the Meteo-France Gale Warning area, fresh to strong NNE trades and seas of 8 to 10 ft are evident north of 18N between the African coast and 25W. To the west, gentle to moderate NE to SE winds and 6 to 7 ft seas are found north of 20N between 25W and 34W/45W. Farther south, gentle to moderate NNE to NE trades and seas of 5 to 7 ft in moderate northerly swell are present from 05N to 20N/16N between 45W and the Windward Islands. Light to gentle winds and seas at 4 to 6 ft in gentle northerly swell prevail for the remainder of the Atlantic Basin. For the forecast W of 55W, the aforementioned 1021 mb high will support fresh to occasionally strong E to SE winds off Hispaniola through Sun. Large northerly swell west of 70W will subside through Sun. Meanwhile, expect fresh to strong southerly flow and building seas north of 29N between northeast Florida and Bermuda through this evening, ahead of a cold front moving off the northeast Florida coast this morning. The front will move east and stall from Bermuda to the Straits of Florida by early Mon. Looking ahead, winds and seas will increase north of the stalled front Mon through mid week with NE swell. $$ Forecaster Chan