Unrated tornado, Gruver, Texas, May 26, 2021

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 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. Unratedthis tornado

   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

Unrated

Date

May 26, 2021

Touchdown

5:56 PM CDT (22:56 UTC)

Lifted

6:00 PM CDT (23:00 UTC)

On the ground

4 minutes

Path length

1.9 miles (3.1 km)

Path width

20 yards (18 m)

Deaths

0

Injuries

0

County

Hansford County

Touchdown point

36.348, -101.457

Lift-off point

36.357, -101.424

Record number

2105261656-01

An upper level storm system, initially over the southwestern United States, approached the area and sent various disturbances across the region. With ample moisture, instability, and increased wind shear, thunderstorms initiated along a dryline and progressed towards the northeast and east. A couple of the storms became supercells, which were the cause of the 4 reported tornadoes on this date. The only tornado that encoutered damage indicators occurred in Perryton. This weak and small tornado received a rating of EF-0 with estimated wind speeds up to 75 mph. The longest tracked tornado, which occurred north of Gruver, was caught on video by multiple storm chasers with a path length approaching 1.9 miles. In addition to the tornados, these supercells produced large hail that in some instances were near or exceeded baseball size.

The track of this tornado was not accessible by road as it moved|through a farm field, but was noted on radar and documented by|storm chasers in the area.

The same storm that caused the first tornado north of Gruver|resulted in a 2nd over the same area about 20 minutes later. This|tornado was documented by storm chasers and noted on radar.

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

18 minutes of warning. NWS AMA issued a tornado warning for this county at 22:38 UTC, 18 minutes before the tornado touched down, in force until 23:30 UTC.

The county was under a tornado watch, issued at 22:16 UTC and running to 03:39 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 Slight Risk, with a 0.05 chance of a tornado within 25 miles. The outlook in force was issued at 19:57 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 Amarillo radar (KAMA), 127 km away, was scanning. The volume nearest the touchdown began at 22:56 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 2021 tornado in TexasEvery tornado in Texas since 1950Warnings in force in Texas nowThe forecast where you are

20 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.