Unrated tornado, Goodnight to Claude, Texas, March 13, 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

March 13, 2021

Touchdown

5:02 PM CST (23:02 UTC)

Lifted

5:11 PM CST (23:11 UTC)

On the ground

9 minutes

Path length

3.1 miles (5.0 km)

Path width

800 yards (732 m)

Deaths

0

Injuries

0

County

Armstrong County

Touchdown point

35.125, -101.236

Lift-off point

35.170, -101.230

Record number

2103131702-01

A very potent upper level system produced widespread hazards from heavy snow across the front range/Rockies to severe weather across the Southern High Plains. The vigorous closed upper low was approached the Four Corners region from the west. A warm front lifted north and northwest across all but the Oklahoma Panhandle and the northwest Texas Panhandle while a sharpening dryline was located over eastern New Mexico. The dryline preceded a Pacific cold front which was also located in eastern New Mexico and swept eastward later in the evening. A broken line of thunderstorms developed ahead of the dryline in eastern New Mexico and tracked north and east into the western and southwestern Texas Panhandle before continuing to move east across the remainder of the eastern Panhandles during the evening hours, growing upscale as the Pacific cold front swept eastward and overtook the dryline. Nine confirmed tornadoes occurred early in the event during the afternoon hours and some of these were large, violent and were on the ground for long periods of time. Three separate instances occurred where two tornadoes were in progress from the same parent thunderstorm at the same time. While traveling across mostly rural areas, the tornadoes did impact several farm homes as well as Palo Duro State Park and Greenbelt Lake.

The track of this tornado is not accessible by road, but was noted on radar and documented by storm chasers in the area.

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

20 minutes of warning. NWS AMA issued a tornado warning for this county at 22:42 UTC, 20 minutes before the tornado touched down, in force until 23:30 UTC.

The county was under a tornado watch, issued at 20:36 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 Moderate Risk, with a 0.15 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.

Amarillo - Rick Husband Intl (AMA), 44 km from the path, in the two hours either side.

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

The Amarillo radar (KAMA), 44 km away, was scanning. The volume nearest the touchdown began at 22:59 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.