000 AXNT20 KNHC 261015 TWDAT Tropical Weather Discussion NWS National Hurricane Center Miami FL 1205 UTC Tue Nov 26 2024 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 1010 UTC. ...SPECIAL FEATURES... ...LONG PERIOD SWELL AND ROUGH TO VERY ROUGH SEAS... Long-period NW swell with 12-15 ft seas is moving through the north central Atlantic Ocean, in the wake of a former front that dissipated earlier. A reinforcing cold front will move into the area today followed by a second set of long-period NW swell with seas to 16 ft, which will propagate through the north central and northeastern Atlantic Ocean subtropical waters through Thursday. Please, read the latest HIGH SEAS FORECAST, that is issued by the National Hurricane Center, at the website - https://www.nhc.noaa.gov/text/MIAHSFAT2.shtml, for details. ...EXCESSIVE RAINFALL IN THE NORTHERN CARIBBEAN SEA... A slow-to-progress potent and large upper trough extends across the Florida peninsula into the western Gulf of Honduras. This system is accompanied by upper jet dynamics and is stimulating a lowering of surface pressures in the western and north-central Caribbean. This is stimulating moisture convergence and building a broad region of precipitable water. Deep convection continues to increase to the south and west of the Haitian peninsula. Two to three days of intermittent periods of heavy rain producing convection are expected under this scenario. This precipitation is also affecting the Turks and Caicos and southern Bahamas as a low pressure develops in the region today and meanders through Wed. The extended period of heavy rain will increase the risks for flash flooding and mudslides and landslides. This information was provided by the International Desk meteorologists at the WPC. Please, refer to the WPC, and/or to your country's local meteorological agency for more details. ...MONSOON TROUGH/ITCZ... The monsoon trough passes through the coastal plains border of Sierra Leone and Liberia to 06N17W. The ITCZ continues from 06N17W to 03N35W to 04N50W. Scattered moderate convection is ongoing from 02N to 07N between 15W and 40W. ...GULF OF MEXICO... A cold front extends from Louisiana SW to southern Texas followed by moderate to fresh northerly winds and preceded by moderate SW winds over the NE Gulf coastal waters. Surface high pressure and associated ridge cover the remainder Gulf waters. The pressure gradient between the ridge and a broad area of low pressure in the western Caribbean support moderate NE winds across the SE Gulf and the eastern Bay of Campeche. Seas basin-wide are slight. For the forecast, the cold front will reach from the Florida Panhandle to Tamaulipas, Mexico this afternoon and then move NE of the area tonight. A second cold front is forecast to enter the NW Gulf waters Thu morning. Moderate to fresh southerly winds will develop over the western Gulf tonight through Wed night ahead of the second front, which will reach from Cedar Key, Florida to near Tampico, Mexico early on Fri, and from the Straits of Florida to near Veracruz, Mexico by Sat morning. The front will exit the basin by Sat evening. Fresh to strong northerly winds and building seas will follow this front. Winds may briefly reach minimal gale force near the Veracruz area on Fri. ...CARIBBEAN SEA... Please, read the SPECIAL FEATURES section, for details about a heavy rainfall event. Heavy showers and tstms continue to affect the north-central and portions of the SW Caribbean under the influence of a broad area of low pressure depicted as a trough that extends across the Windward Passage to the Colombia offshore waters. Surface high pressure prevails N of the area continue to support moderate to fresh easterly winds over the central and eastern Caribbean, and moderate to fresh NE winds over the NW basin. Seas are moderate to 6 ft basin-wide, likely rough in the area of strong convection. For the forecast, the pressure gradient between a broad area of low pressure over the western Caribbean and high pressure over the SW N Atlantic will continue to support moderate to fresh easterly winds over the central and eastern Caribbean, and moderate to fresh NE winds over the NW basin through Sat night. Locally strong NE winds are likely over the NW Caribbean tonight and Wed. Otherwise, a low pressure will develop over the SW Caribbean today and meander over the Costa Rica and Nicaragua offshore waters through the weekend supporting scattered showers and tstms. ...ATLANTIC OCEAN... Please, read the SPECIAL FEATURES section, for details about long period swell. Scattered showers and tstms continue to affect the central and southern Bahamas as well as the Turks and Caicos where a surface trough is generating the strongest convection. Surface high pressure dominates the remainder SW Atlantic subtropical waters, which is supporting moderate to fresh winds S of 25N and moderate to rough seas. Strong winds are ongoing over the southern Bahamas offshore waters as a low pressure develops over the region this morning. Long period NW swell with 8-15 ft seas continue to affect the central subtropical waters while another high and associated ridge covers the eastern subtropical waters. For the forecast, high pressure and associated ridging will prevail across the offshore waters N of 28N. The pressure gradient between the high and developing low pressure near the southern Bahamas will support moderate to fresh easterlies S of 28N and E of 70W through Thu. Fresh to locally strong NE winds are forecast for the central and southern Bahamas offshore waters as well as the Great Bahama Bank as the developing low meanders in that region before opening back to a surface trough Wed evening. Afterward, the trough will shift west and dissipate over Cuba Thu night. The next cold front will enter the NE Florida offshore waters tonight before stalling and lifting N of the area late Wed. A stronger cold front is forecast to move offshore NE Florida Thu night into Fri. Moderate to fresh winds are expected to affect the northern offshore waters during the passage of the front, which is forecast to reach from Bermuda to the northern Bahamas by Sat morning. $$ Ramos