2011 Joplin tornado
The 2011 Joplin tornado was a catastrophic EF5-rated multiple-vortex tornado that struck Joplin, Missouri, late in the afternoon of Sunday, May 22, 2011. It was part of a larger late-May tornado outbreak and reached a maximum width of nearly during its path through the southern part of the city. This particular tornado was unusual in that it intensified in strength and grew larger in size at a very fast rate. The tornado tracked eastward across the city, and then continued eastward across Interstate 44 into rural portions of Jasper County and Newton County. It was the third tornado to strike Joplin since May 1971.
Tornado climatology
On average, the United States experiences 100,000 thunderstorms each year, resulting in more than 1,200 tornadoes and approximately 50 deaths per year. The deadliest U.S. tornado recorded is the 18 March 1925, Tri-State Tornado that swept across southeastern Missouri, southern Illinois and southern Indiana, killing 695 people. The biggest tornado outbreak on record—with 353 tornadoes over the course of just 3 1/2 days, including four F5 and eleven F4 tornadoes—occurred starting on 25 April 2011 and intensifying on 26 April and especially the record-breaking day of 27 April before ending on 28 April. It is referred to as the 2011 Super Outbreak. Previously, the record was 148 tornadoes, dubbed the 1974 Super Outbreak. Another such significant storm system was the Palm Sunday tornado outbreak of 1965, which affected the United States Midwest on 11 April 1965. A series of continuous tornado outbreaks is known as a tornado outbreak sequence, with significant occurrences in May 1917, 1930, 1949, and 2003.