EF4 Shawnee tornado, Oklahoma, May 19, 2013

1. EF065 to 85 mph

   Light damage. Surface peeled off some roofs, gutters and siding damaged, branches broken, shallow-rooted trees pushed over.

2. EF186 to 110 mph

   Moderate damage. Roofs badly stripped, mobile homes overturned or badly damaged, exterior doors lost, windows broken.

3. EF2111 to 135 mph

   Considerable damage. Roofs torn off well-built houses, frame homes shifted on their foundations, mobile homes destroyed, large trees snapped or uprooted, cars lifted off the ground.

4. EF3136 to 165 mph

   Severe damage. Whole stories of well-built houses destroyed, large buildings badly damaged, trains overturned, trees debarked, heavy cars lifted and thrown.

5. EF4166 to 200 mphthis tornado

   Devastating damage. Well-built houses leveled, structures with weak foundations moved some distance, cars thrown and large missiles generated.

6. EF5over 200 mph

   Incredible damage. Strong frame houses swept off their foundations, car-sized missiles thrown more than 100 meters, steel-reinforced concrete badly damaged, high-rise buildings deformed.

7. Unrated

   The survey recorded a tornado but could not put a number on it, most often because it crossed open country and damaged nothing a rating can be read from.

Rating

EF4

Date

May 19, 2013

Touchdown

6:00 PM CDT (23:00 UTC)

Lifted

6:50 PM CDT (23:50 UTC)

On the ground

50 minutes

Path length

23.0 miles (37.0 km)

Path width

1,500 yards (1372 m)

Deaths

2

Injuries

10

Counties

Cleveland and Pottawatomie counties

Touchdown point

35.253, -97.300

Lift-off point

35.423, -96.981

Record number

1305191700-01

524 damage points were recorded along this path by NWS OUN and NWS TSA, in the Damage Assessment Toolkit the survey teams carry. The strongest indicator was rated EF4. The highest wind the damage implies is 175 mph.

• house on cinder blocks slid to the ne; otherwise damage would have been in EF1 category based on roof/wall damage on other side from where this photo was taken
• 2/3 of roof torn off home; well built with 2x6s every 12"; home now deemed structurally unsound and will have to be demolished.
• photo from west side of house; exterior wall blown inward; garage door was blown outward
• numerous trees snapped or uprooted

Survey points are preliminary and are the raw material the published rating was built from. Source: NWS Damage Assessment Toolkit.

A moist and very unstable airmass was in place over the eastern two thirds of Oklahoma, to the east of a dryline. Additionally, strong wind shear was present as a mid-level jet streak carved into the southern Plains. Several supercells developed along the dryline during the mid and late afternoon hours, producing large hail. Two supercells in central Oklahoma also produced tornadoes, including a few significant, damaging tornadoes.

A long track tornado began in Cleveland County in east Norman to the north of Lake Thunderbird along 96th Avenue to the south of Tecumseh Road. The tornado moved northeast, crossing the eastern arm of Lake Thunderbird. A number of homes were significantly damaged as the tornado moved east-northeast through neighborhoods from near Indian Hills Road and 168th Avenue SE to the Pottawatomie County line. The tornado then moved into Pottawatomie County.

The large tornado moved east-northeast into Pottawatomie County then curving northeast as it approached State Highway 102. The tornado moved through a mobile home park north of Independence Road after crossing State Highway 102. Just northeast of the mobile home park, a permanent home was destroyed with much of the debris blown well to the northeast. It continued northeast crossing Interstate 40 near the intersection of US-177, then curved north-northeast finally dissipating near Wolverine Road and Coker Road. One fatality occurred in the mobile home park, and another man was killed in his vehicle.

The deaths

2 direct deaths are recorded for this tornado, each with what Storm Data knows of it.

From NOAA NCEI's Storm Events Database, the narrative the local forecast office wrote for Storm Data.

20 minutes of warning. NWS OUN issued a tornado warning for this county at 22:40 UTC, 20 minutes before the tornado touched down, in force until 23:15 UTC.

The county was under a tornado watch, issued at 19:15 UTC and running to 02:48 UTC.

Every warning and watch covering the touchdown point that day, from the Iowa Environmental Mesonet's archive of National Weather Service products. Lead time is measured from the issue of the warning in force to the touchdown time in the database, both of which were recorded to the minute by different people.

The Storm Prediction Center had this point in a Moderate Risk, with a 0.10 chance of a tornado within 25 miles, in the hatched area where significant tornadoes were expected. The outlook in force was issued at 19:40 UTC.

SPC's Day 1 convective outlook as it stood when the tornado began, read at the touchdown point. The same archive is on the radar archive.

The radiosonde launches on either side of the tornado, from the nearest station that was launching then, drawn and analyzed the way Storm Lab does: the same diagram, the same parcel and shear definitions SPC's mesoanalysis uses.

The Norman radar (KTLX), 12 km away, was scanning. The volume nearest the touchdown began at 23:01 UTC.

Open the radar archive at this moment, over the track

Reflectivity and velocity, decoded from the Level II archive in the browser. Volumes take a few seconds to open the first time.

Local storm reports within 60 km of the path, in the three hours either side.

From the Iowa Environmental Mesonet's archive of National Weather Service local storm reports.

The live radar over the trackEvery 2013 tornado in OklahomaEvery tornado in Oklahoma since 1950Warnings in force in Oklahoma nowThe forecast where you are

26 more were confirmed in the United States that day.

Ratings are the survey's, read off the damage rather than measured; the rating scale is above. Tornado counts rise through the record as reporting improved, so a year in the 1950s is not comparable with one today except for the strongest tornadoes, which were always noticed.

NOAA Storm Prediction Center tornado database, 1950-2025, the official record kept by NOAA's Storm Prediction Center.