EF2 tornado, Monterey to Bancroft, 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 mph

   Moderate damage. Roofs badly stripped, mobile homes overturned or badly damaged, exterior doors lost, windows broken.

3. EF2111 to 135 mphthis tornado

   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

EF2

Date

December 15, 2021

Touchdown

3:44 PM CST (21:44 UTC)

Lifted

3:54 PM CST (21:54 UTC)

On the ground

10 minutes

Path length

11.2 miles (18.1 km)

Path width

200 yards (183 m)

Deaths

0

Injuries

0

County

Cuming County

Touchdown point

41.910, -96.750

Lift-off point

42.070, -96.690

Record number

2112151544-01

28 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 120 mph.

• Multiple well constructed large farm buildings destroyed.
• Damage to large barn roof, trees snapped, siding removed
• 5 poles were broken just down the road. Was bolted down but open to south and older building.
• 5 large wooden transmission poles broken

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 in a field near 3rd road south of C road and quickly moved northeast to cause roof damage to large animal barns where a substantial amount of roofing tin were removed. The tornado proceeded across open fields before severely impacting a farm near 4th and E road. The farm place had a small shed blown approximately 100 yards. A second brand new larger shed was completely destroyed and a very large shed with equipment inside was also completely destroyed. There was minor roof and siding damage to the home and to another large shed, as well as some fences. The tornado proceeded northeast to another hog farm where it removed large sections of roof from two large barns. The debris were deposited well into a field downstream. The track was then intermittent for 1.5 miles as there were few if any available damage indicators in ag fields before it caused additional damage to 5 power poles and another animal barn where much of the barn was removed and blown into the nearby trees. The tornado appeared to dissipate at that point.

A brief tornado developed in a field and then travelled north northeast where it snapped 5 wooden power poles and then caused tree damage in a grove of trees.

An intermittent path of damage across open fields but also managed to snap off power poles in multiple locations, and also caused damage to a shed.

A brief tornado snapped trees and caused minor roof damage to a home before destroying a 40 by 60 foot shed and moving a farm gravity wagon approximately 100 yards while continuing to damage trees. Witnesses noted that this was a brief tornado but they did see the funnel cloud at the site of the damage.

This tornado impacted several farms and residences along its 11 mile track with at least 5 points suggesting EF2 damage with maximum winds of approximately 120 mph. This tornado also had one of the wider paths in this region on December 15 where at one point the tree pattern suggested 200 yard width. The tornado destroyed several barns, including some well-built large structures. It also caused substantial power line damage, snapping several power poles in multiple locations.

Tornado segment 1 of 2. This tornado began southwest of Bancroft, uprooting several large pine trees, collapsing a windmill, and tearing shingles of the roof of a home. The tornado continued northeast, passing just northwest of Bancroft and entered Thurston County northwest of Rosalie.

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

19 minutes of warning. NWS OAX issued a tornado warning for this county at 21:25 UTC, 19 minutes before the tornado touched down, in force until 22:00 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.

Wayne (LCG), 35 km from the path, in the two hours either side.

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

The Omaha radar (KOAX), 80 km away, was scanning. The volume nearest the touchdown began at 21:41 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.