Tornado climatology
The United States averaged 1,274 tornadoes per year in the last decade. April 2011 saw the most tornadoes ever recorded for any month in the US National Weather Service's history, 875; the previous record was 542 in one month. It has more tornadoes yearly than any other country and reports more violent (F4 and F5) tornadoes than anywhere else.
Multiple-vortex tornado
The largest tornado ever documented was a multiple-vortex tornado; it struck El Reno, Oklahoma on May 31, 2013 taking the lives of tornado researcher Tim Samaras, his son Paul, and their TWISTEX colleague, Carl Young. This storm also took the life of local amateur chaser, Richard Henderson. It had a maximum width of and a maximum recorded windspeed of at least , however, due to a lack of property damage, the tornado achieved a rating of EF3 on the Enhanced Fujita scale. Nevertheless, the El Reno tornado is one of the two strongest tornadoes ever recorded in terms of maximum wind speeds, the other being the 1999 Bridge Creek–Moore tornado.