Tornado outbreak of May 26–31, 2013

Tornado outbreak of May 26–31, 2013

The storm system responsible for the tornado outbreak at 6:10 p.m. CDT May 31
Type	Tornado outbreak
Duration	May 26–31, 2013
Tornadoes confirmed	115
Max rating1	EF3 tornado
Duration of tornado outbreak2	5 days, 10 hours, 43 minutes
Highest winds	>295 mph (475 km/h) (El Reno, OK EF3 tornado on May 31)(The winds were not used in the survey; thus, the tornado was rated EF3 instead of EF5.) 87 mph (140 km/h) (Tinker Air Force Base, OK non-tornadic on May 31)
Largest hail	5.25 inches (13.3 cm) in diameter NW of Montrose, Kansas on May 27
Damage	Unknown
Casualties	9 fatalities confirmed (+18 non-tornadic), 172 injuries
1Most severe tornado damage; see Enhanced Fujita scale 2Time from first tornado to last tornado Part of the tornadoes of 2013

¹Most severe tornado damage; see Enhanced Fujita scale ²Time from first tornado to last tornado

The tornado outbreak of May 26–31, 2013 was a prolonged and widespread tornadic event that affected a large portion of the United States. The outbreak was the result of a slow-moving but powerful storm system that produced several strong tornadoes across the Great Plains states, especially in Kansas and Oklahoma. Other strong tornadoes caused severe damage in Nebraska, Missouri, Illinois, and Michigan. The outbreak extended as far as New York. 27 fatalities were reported in total, with nine resulting from tornadoes (eight in Oklahoma and one in Arkansas).

By far the most significant tornado of the outbreak was an extremely large EF3 that struck areas near the town of El Reno, Oklahoma on May 31. With a maximum width of 2.6 miles (4.2 km), it was the largest tornado on record. The second highest wind speeds recorded on Earth, around 295 miles per hour (475 km/h), were also observed in this tornado. The twister was responsible for eight deaths, including famous storm chaser Tim Samaras, his son Paul, and Carl Young as a result of being caught off-guard by the tornado's unprecedented width. In addition, the tornado caused an unknown amount of injuries.

On May 22, an upper-level low moved eastward over the Western United States, with forward progression limited by a blocking high around the Northern Plains and Great Lakes. With ample low-level moisture streaming north ahead of the low into an area of moderate instability, scattered severe weather was anticipated over parts of Colorado, Kansas, and Nebraska starting on May 24.