2013 El Reno tornado
Storm development and track
### Storm development and track

[thumb\|left\|[Phased array](/wiki/Phased_array "Phased array") radar ([reflectivity](/wiki/Weather_radar%23Reflectivity "Weather radar#Reflectivity"); [click to animate](//upload.wikimedia.org/wikipedia/commons/3/3a/May_31%2C_2013_Oklahoma_Phased_Array_Radar_Reflectivity.gif)) of the series of supercell thunderstorms that impacted the Oklahoma City metropolitan area on May 31\.](/wiki/File:May_31%2C_2013_Oklahoma_Phased_Array_Radar_Reflectivity.gif "May 31, 2013 Oklahoma Phased Array Radar Reflectivity.gif")

A quasi\-linear complex of thunderstorms began developing near the [Highway 81](/wiki/U.S._Route_81_in_Oklahoma "U.S. Route 81 in Oklahoma") corridor west of Oklahoma City between 4:00 and 4:45 p.m. CDT, and rapidly reached severe intensity. At 5:33 p.m. CDT (2233 UTC), the [National Weather Service](/wiki/National_Weather_Service "National Weather Service") [Weather Forecast Office](/wiki/National_Weather_Service_Norman%2C_Oklahoma "National Weather Service Norman, Oklahoma") in [Norman, Oklahoma](/wiki/Norman%2C_Oklahoma "Norman, Oklahoma") issued a [tornado warning](/wiki/Tornado_warning "Tornado warning") for [Canadian County](/wiki/Canadian_County%2C_Oklahoma "Canadian County, Oklahoma"), prompted by increasingly strong tornadic circulation exhibited in the southernmost supercell of this complex.

At 6:03 p.m. CDT (2303 UTC), a large tornadic [wall cloud](/wiki/Wall_cloud "Wall cloud") formed and touched down, initially in the form of several smaller [sub\-vortices](/wiki/Multiple-vortex_tornado "Multiple-vortex tornado"),  west\-southwest of [El Reno](/wiki/El_Reno%2C_Oklahoma "El Reno, Oklahoma"). The tornado ultimately attained EF3 intensity during its existence, according to ground surveys. As the tornado passed south of El Reno across U.S. 81, it grew to an unprecedented width of , becoming the [widest known tornado](/wiki/Tornado_records "Tornado records") ever recorded in the United States. At 6:28 p.m. CDT (2328 UTC), the storm began moving into more densely populated areas of Canadian County while maintaining its intensity. This prompted the National Weather Service office in Norman to issue a [tornado emergency](/wiki/Tornado_emergency "Tornado emergency") for [Yukon](/wiki/Yukon%2C_Oklahoma "Yukon, Oklahoma"), Richland, [Wiley Post Airport](/wiki/Wiley_Post_Airport "Wiley Post Airport"), [Bethany](/wiki/Bethany%2C_Oklahoma "Bethany, Oklahoma"), [The Village](/wiki/The_Village%2C_Oklahoma "The Village, Oklahoma"), and eastern El Reno, as the tornado was projected to track toward western portions of the Oklahoma City metropolitan area. Within minutes, the tornado turned northeast and soon passed directly over [Interstate 40](/wiki/Interstate_40 "Interstate 40") at around 6:42 p.m. CDT (2342 UTC). Shortly thereafter, the tornado lifted off the ground as it neared Banner Road. Overall, the tornado was on the ground for 40 minutes along a  path.

A strong [anticyclonic](/wiki/Anticyclonic_tornado "Anticyclonic tornado") multivortex [satellite tornado](/wiki/Satellite_tornado "Satellite tornado") also formed southeast of the primary tornado at approximately 6:28 pm CDT (2328 UTC), and remained on the ground for 15 minutes before lifting at 6:43 (2343 UTC). Such companion tornadoes tend to be observed with especially large and intense tornadoes, although this was the first documented multiple\-vortex anticyclonic tornado of this kind.


Can multiple-vortex tornadoes occur without a wall cloud forming first?