Severe storms also bring a risk of tornadoes. Meteorological events include rain, snow, blizzards, thunderstorms, hail, derechos, tornadoes, and high-velocity straight-line winds. Structural damage was generally minimal, occurring from the tornadoes and severe thunderstorms. Tornadoes and tropical cyclones are common. Stronger thunderstorm cells are capable of producing tornadoes and waterspouts. South Carolina is also prone to tropical cyclones and tornadoes. There are observed correlations between tornadoes and patterns of lightning. Two of the five deadliest tornadoes in U.S. history have occurred in the state. Amarillo is no stranger to devastating tornadoes. This outbreak spawned over 66 tornadoes in Oklahoma alone. Urban centres are not immune from the threat of severe tornadoes. Three damaging tornadoes occurred in the state. It was part of an outbreak that produced 30 tornadoes around the region. Fort Smith, Arkansas sustained considerable damage from two separate EF1 tornadoes. Most of the tornadoes occurred in Illinois.