2021 Western Kentucky tornado

During the late evening hours of Friday, December 10, 2021, a devastating high-end EF4 tornado, sometimes referred to as the Western Kentucky tornado, Mayfield tornado, or The Beast, tracked a significant distance across Western Kentucky, United States, producing severe-to-catastrophic damage in numerous towns, including Mayfield, Princeton, Dawson Springs, and Bremen. This tornado was the second significant tornado in an exceedingly long-tracked tornado family; it began just inside northern Obion County, Tennessee – a few miles after another long-tracked tornado that traveled through northeast Arkansas, the Missouri Bootheel, and northwest Tennessee – and dissipated in western Obion County. After crossing into Kentucky, the tornado moved through eleven counties of the Jackson Purchase and Western Coal Field regions, at times becoming wrapped in rain during its almost three-hour lifespan that covered 165.6 miles (266.5 km). It was the deadliest and longest-tracked tornado in an outbreak that produced numerous, strong tornadoes in several states; this tornado caused 57 deaths.

Early estimates suggested the tornado family, which some media outlets described as a "Quad-State tornado" due to the storm's long track and similarity to the 219-mile (352 km) Tri-State tornado of 1925, might have traveled 250 miles (400 km) on the ground, making it the longest-tracked tornado in history. Storm surveys found the majority of the storm's path consisted of two separate EF4 tornadoes, and three weak, short-lived tornadoes in between them in northwestern Obion County, Tennessee. The parent supercell that produced the two EF4 tornadoes, and eleven tornadoes in total, later became known as the Quad-State supercell.

After the tornado, a state of emergency and federal disaster was declared by Governor Andy Beshear and President Joe Biden on December 11. The death toll of 57 was the highest from a tornado in the month of December in U.S. history, while also being the deadliest tornado since 2011. In Mayfield, the damage was the most severe and was considered by some NWS analysts in a case study as bordering on EF5 intensity, prompting discussion on the intensity of high-end tornadoes and damage requirements. Additionally, soon after the outbreak subsided, multiple workers at the Mayfield Consumer Products candle factory that was destroyed when the long-track EF4 tornado hit Mayfield, Kentucky, alleged that supervisors told them they would be fired if they left their shifts early ahead of the storm's direct hit on the city. Company spokespeople have denied the allegations. On December 17, it was reported that multiple workers (only one was named due to fear of reprisal) filed a class-action lawsuit against the company. The lawsuit alleged that the company had up to three and a half hours to allow employees to leave before the tornado hit the factory and showed a flagrant indifference to the rights of the workers.