EF1 tornado, Short to Leecreek, Oklahoma, May 27, 2017

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 mphthis tornado

   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 mph

   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

EF1

Date

May 27, 2017

Touchdown

11:45 PM CDT (04:45 UTC)

Lifted

11:56 PM CDT (04:56 UTC)

On the ground

11 minutes

Path length

11.2 miles (18.0 km)

Path width

700 yards (640 m)

Deaths

0

Injuries

0

Property damage

$30,000

Counties

Crawford and Sequoyah counties

Touchdown point

35.580, -94.491

Lift-off point

35.643, -94.313

Record number

1705272245-01

29 damage points were recorded along this path by NWS TSA, in the Damage Assessment Toolkit the survey teams carry. The strongest indicator was rated EF1. The highest wind the damage implies is 107 mph.

• Roof was add-on, not original roof of structure

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

Strong to severe thunderstorms developed during the late afternoon hours of the 27th along and ahead of a cold front that was moving into eastern Oklahoma. Very unstable air over the area, combined with strong deep-layer wind shear, resulted in widespread severe weather to develop. Several tornadoes, hail up to softball size, and damaging wind gusts occurred with the strongest storms.

Strong to severe thunderstorms developed during the late afternoon hours of the 27th along and ahead of a cold front that was moving into eastern Oklahoma. Very unstable air over the area ahead of the front, combined with strong deep-layer wind shear, resulted in widespread severe weather to develop. A tornado and damaging wind gusts occurred with the strongest storms as they moved across northwestern Arkansas.

This is the first segment of a two segment tornado. In Sequoyah County, this tornado uprooted trees and snapped large tree limbs as it moved east-northeast, crossing into Crawford County, Arkansas west of Uniontown. Based on this damage, maximum estimated wind in this segment of the tornado was 90 to 100 mph.

This is the second segment of a two segment tornado. In Crawford County, this tornado destroyed the roof of a mobile home, damaged outbuildings, and uprooted trees near the state line. Numerous trees were snapped and uprooted as it moved across Highway 59 and Arkansas 220, finally dissipating after crossing White Water Road, east-southeast of Natural Dam. Based on this damage, maximum estimated wind in this segment of the tornado was 95 to 105 mph.

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

No tornado warning for this county appears in the archive as in force at the moment the tornado touched down.

The county was under a tornado watch, issued at 21:05 UTC and running to 05:00 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 00:44 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.

Fort Smith Municipal (FSM), 31 km from the path, in the two hours either side.

From the Iowa Environmental Mesonet's archive of airport observations.

The Western Arkansas radar (KSRX), 36 km away, was scanning. The volume nearest the touchdown began at 04:47 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 2017 tornado in OklahomaEvery tornado in Oklahoma since 1950Warnings in force in Oklahoma nowThe forecast where you are

13 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.