EF1 tornado, Platte Center to (Olu)Columbus Arpt, Nebraska, December 15, 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 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

December 15, 2021

Touchdown

3:03 PM CST (21:03 UTC)

Lifted

3:04 PM CST (21:04 UTC)

On the ground

1 minutes

Path length

0.8 miles (1.3 km)

Path width

30 yards (27 m)

Deaths

0

Injuries

0

County

Platte County

Touchdown point

41.530, -97.490

Lift-off point

41.540, -97.480

Record number

2112151503-01

19 damage points were recorded along this path by NWS OAX, in the Damage Assessment Toolkit the survey teams carry. The strongest indicator was rated EF2. The highest wind the damage implies is 115 mph.

• Wind entered doors and shifted building to collapse.
• Irrigation pivot overturned. This is the likely start point of the tornado track.
• Shingle damage. Semi trailer flipped over
• Snapped tree trunk next door.

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

A low pressure system brought strong (both thunderstorm, and non-thunderstorm) winds, tornadoes, dust, snow, and record temperatures into eastern Nebraska and western Iowa. The event was determined to be a derecho meeting the criteria of wind damage extending more than 250 miles, including wind gusts of at least 58 mph and numerous gusts of at least 75 mph.

A tornado developed over an open field south of town and north of the creek where it tipped over two sections of an irrigation pivot. The tornado proceeded north northeast into Platte Center, causing damage to a garage and snapping several trees. The maximum damage occurred between 2nd and 4th streets where a large metal building with wood construction had the wind enter the doors, uplift the roof, and collapse the walls as the entire building shifted and collapsed to the northeast. Very large trees were blown down and one home lost much of its roof. The damage became less notable over the next block and dissipated near the elementary school.

A narrow, fast-moving, tornado began in the parking lot of a business along Howard Blvd where it tipped over a semi trailer and proceeded to cause roof, siding, fence, and tree damage. Approximately one block later, it caused the worst damage of the entire track where an attached garage and entire roof were removed from a ranch home. Much of the roof was deposited 20 to 100 yards downstream. The tornado proceeded to produce sporadic damage over the next two blocks and then a more consistent damage path for a 6 block period where many homes had minor to moderate roof damage and several trees were snapped or uprooted. There was then another 5 blocks of sporadic minor to moderate tree and roof damage followed by a 2 block stretch of continuous minor to moderate roof and siding damage. The tornado then travelled across open fields until reaching the Indian Hills neighborhood where it snapped two power poles and caused generally minor damage to a fence and shingles, with no further damage downstream. The entire 2.7 mile track occurred in approximately 2 minutes.

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

24 minutes of warning. NWS OAX issued a tornado warning for this county at 20:39 UTC, 24 minutes before the tornado touched down, in force until 21:03 UTC.

The county was under a tornado watch, issued at 19:23 UTC and running to 22:18 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 Enhanced Risk, with a 0.05 chance of a tornado within 25 miles. The outlook in force was issued at 19:28 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 Omaha radar (KOAX), 96 km away, was scanning. The volume nearest the touchdown began at 21:01 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 2021 tornado in NebraskaEvery tornado in Nebraska since 1950Warnings in force in Nebraska nowThe forecast where you are

124 more were confirmed in the United States that day.

All 125 of them

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.