Christmas Eve Storms Hit United States
December 25, 2015
A tornado is a rapidly rotating column of air that can develop under a large, anvil-shaped thundercloud. First, a dark wall cloud forms underneath the thundercloud. In most cases, a twisting, funnel-shaped cloud then descends from the wall cloud and touches the ground. Almost all tornadoes in the Northern Hemisphere rotate as shown in the diagram—counterclockwise when viewed from above. World Book illustration by Bruce Kerr
Heavy storms hit the Midwest and South on December 24, killing at least 14 people. On Christmas Eve, more than 20 tornadoes touched down in Arkansas, Illinois, Indiana, Michigan, Mississippi, and Tennessee. Worst hit was the Southern State of Mississippi, which was struck with 14 tornadoes. Seven of the fourteen people killed were in Mississippi, and the state saw at least 40 people injured in the storms. Violent storms also struck the Southern States of Tennessee and Arkansas; six were killed in Tennessee and 1 in Arkansas. In Georgia, another Southern State, heavy rains led to widespread flooding and mudslides.
Tornadoes and thunderstorms are not unheard of in the United States in December, especially in the warmer southern region. Meteorologists, however, attributed the ferocity of the December 24 storms to unseasonably warm weather across much of the northeastern United States, caused by the El Niño. An El Niño is a part of the interaction between Earth’s atmosphere and the tropical waters of the Pacific Ocean. It occurs about every two to seven years, and it can affect the climate throughout the world. On December 24 in New York City, the high temperature was 72 °F (22 °C), the warmest Christmas Eve ever seen in the Big Apple and about 30 degrees warmer than the average temperature. Similar temperatures made much of the northeastern United States warmer than states in the West, such as California and Arizona, the usual places for a green Christmas.
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