Unrated tornado, Graham Chapel, Texas, May 23, 2020

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 23, 2020

Touchdown

6:14 PM CDT (23:14 UTC)

Lifted

6:25 PM CDT (23:25 UTC)

On the ground

11 minutes

Path length

0.4 miles (0.6 km)

Path width

30 yards (27 m)

Deaths

0

Injuries

0

County

Garza County

Touchdown point

32.995, -101.464

Lift-off point

32.998, -101.459

Record number

2005231714-01

Widespread supercell thunderstorms developed across the South Plains on the afternoon and evening of the 23rd producing very large hail, a tornado, and flash flooding. ||From the night of the 22nd through the morning of the 23rd, a dryline surged westward allowing abundant low level moisture to return to the region. This dryline mixed to the east during the afternoon stalling around US Highway 385. A capping inversion initially kept convective initiation from occurring until late in the afternoon under a very unstable atmosphere with CAPE values in excess of 4000 J/kg. Initially, the most intense thunderstorm developed and became anchored over southwestern Garza County. This supercell exhibited strong rotation at low and mid levels of the storm. Several storm chasers observed a tornado over open land that lasted for about 11 minutes. Because of the very slow storm motion of this thunderstorm, the tornado was nearly stationary for its entire lifetime. A lack of roads in the path of the tornado prevented a storm survey from being completed, thus this tornado could not be rated.|Heavy rain fell over an extended period of time in Garza County due to the storm's nearly stationary movement. As a result, a portion of Farm to Market road 669 south of Post was washed out.||The thunderstorms that developed in the southeastern South Plains generated a strong outflow boundary which then moved through the central South Plains. This outflow boundary caused scattered thunderstorms to grow over Lubbock County in which many of these became severe over multiple parts of the city of Lubbock. Hail up to two inches was reported in the city of Lubbock along with wind gusts up to 62 mph. This outflow boundary continued to move northward creating additional severe thunderstorms over the extreme south-central Texas Panhandle. One of these storms produced hail up to three inches in diameter in the city of Silverton (Briscoe County) leading to widespread damage to vehicles.||Trailing stratiform precipitation from decaying thunderstorms generated a couple of non-thunderstorm severe wind gusts. One of these occurred at Caprock Canyons State Park where a Texas Tech University West Texas mesonet site measured a wind gust to 58 mph. The other was at the Automated Surface Observing System at Childress Municipal Airport measuring a gust to 58 mph.

A supercell thunderstorm became anchored over southwestern Garza County for a few hours. During the lifespan of this supercell, it produced a tornado which was widely captured by storm chasers. The time of the tornado reported by storm chasers was distinctly correlated with the strongest low level rotation from KLBB WSR-88D radar imagery. This tornado remained out over open land in southwestern Garza County between Farm to Market Road 669 and the edge of the caprock. Because of this, any damage was inaccessible due to lack of roads and therefore an EF-U rating was assigned.

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

31 minutes of warning. NWS LUB issued a tornado warning for this county at 22:43 UTC, 31 minutes before the tornado touched down, in force until 23:15 UTC.

The county was under a severe thunderstorm watch, issued at 20:06 UTC and running to 03:00 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 Slight Risk, with a 0.02 chance of a tornado within 25 miles. The outlook in force was issued at 19:55 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 Lubbock radar (KLBB), 80 km away, was scanning. The volume nearest the touchdown began at 23:12 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 2020 tornado in TexasEvery tornado in Texas since 1950Warnings in force in Texas 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.