Tornadoes · United States · Nebraska · 2021
EF2 tornado, Platte Center to (Olu)Columbus Arpt, Nebraska, December 15, 2021
From Platte Center to (Olu)Columbus Arpt, this EF2 tornado ran 2.7 miles across Platte County on December 15, 2021, touching down at 3:04 PM CST and reaching 50 yards wide. It killed nobody and injured 2.
The rating scale
Tracks are drawn in the color of the rating. The Enhanced Fujita scale rates the damage rather than measuring the wind: the speeds are what that damage is taken to imply.
EF065 to 85 mph
Light damage. Surface peeled off some roofs, gutters and siding damaged, branches broken, shallow-rooted trees pushed over.
EF186 to 110 mph
Moderate damage. Roofs badly stripped, mobile homes overturned or badly damaged, exterior doors lost, windows broken.
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.
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.
EF4166 to 200 mph
Devastating damage. Well-built houses leveled, structures with weak foundations moved some distance, cars thrown and large missiles generated.
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.
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.
The record
- Rating
- EF2
- Date
- December 15, 2021
- Touchdown
- 3:04 PM CST (21:04 UTC)
- Lifted
- 3:06 PM CST (21:06 UTC)
- On the ground
- 2 minutes
- Path length
- 2.7 miles (4.4 km)
- Path width
- 50 yards (46 m)
- Deaths
- 0
- Injuries
- 2
- County
- Platte County
- Touchdown point
- 41.440, -97.380
- Lift-off point
- 41.470, -97.350
- Record number
- 2112151504-01
The damage survey
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.
What the Weather Service recorded
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.
The warnings
14 minutes of warning. NWS OAX issued a tornado warning for this county at 20:50 UTC, 14 minutes before the tornado touched down, in force until 21:30 UTC.
The county was under a tornado watch, issued at 19:23 UTC and running to 22:18 UTC.
| Issued (UTC) | Expired | Product | Office |
|---|---|---|---|
| 15:00 UTC | 08:20 UTC | High Wind Watch | OAX |
| 18:00 UTC | 03:00 UTC | High Wind Warning | OAX |
| 19:23 UTC | 22:18 UTC | Tornado Watch | OAX |
| 20:19 UTC | 21:15 UTC | Severe Thunderstorm Warning | OAX |
| 20:39 UTC | 21:03 UTC | Tornado Warning | OAX |
| 20:50 UTC | 21:30 UTC | Tornado Warning | OAX |
| 20:59 UTC | 21:30 UTC | Tornado Warning | OAX |
| 21:06 UTC | 21:30 UTC | Tornado Warning | OAX |
| 21:13 UTC | 21:37 UTC | Severe Thunderstorm Warning | OAX |
| 03:00 UTC | 06:00 UTC | Wind Advisory | OAX |
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 forecast that day
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 air that afternoon
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.
Omaha, NE (KOAX), 12:00Z
9.1 hours before the tornado, 84 km from the path. December 15, 2021.
- Mixed-layer CAPE
- 0 J/kg
- Mixed-layer CIN
- -103670 J/kg
- Surface CAPE
- 0 J/kg
- Mixed-layer LCL
- 2165 m above ground
- 0-6 km bulk shear
- 42 kt
- 0-1 km bulk shear
- 38 kt
- 0-1 km storm-relative helicity
- 346 m²/s²
- 0-3 km storm-relative helicity
- 384 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
- 0-3 km lapse rate
- 3.2 K/km
Omaha, NE (KOAX), 00:00Z
2.9 hours after it, 84 km from the path. December 16, 2021.
- Mixed-layer CAPE
- 4 J/kg
- Mixed-layer CIN
- -66 J/kg
- Surface CAPE
- 69 J/kg
- Mixed-layer LCL
- 1685 m above ground
- 0-6 km bulk shear
- 103 kt
- 0-1 km bulk shear
- 47 kt
- 0-1 km storm-relative helicity
- -450 m²/s²
- 0-3 km storm-relative helicity
- -705 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
- 0-3 km lapse rate
- 6.4 K/km
The surface observations
Columbus Municipal (OLU), 2 km from the path, in the two hours either side.
| Time (UTC) | Temp (°F) | Dew point (°F) | Wind | Gust (kt) | Pressure (mb) | Weather |
|---|---|---|---|---|---|---|
| 19:05 UTC | 170° 22 kt | 992.9 | -RA | |||
| 19:10 UTC | 160° 31 kt | 992.2 | -RA | |||
| 19:15 UTC | 170° 26 kt | 37 | 992.2 | -RA | ||
| 19:20 UTC | 160° 22 kt | 992.2 | ||||
| 19:25 UTC | 160° 24 kt | 991.9 | ||||
| 19:29 UTC | 66.2 | 55.4 | 160° 22 kt | 32 | 991.9 | |
| 19:30 UTC | 160° 21 kt | 28 | 991.9 | |||
| 19:35 UTC | 170° 29 kt | 39 | 991.5 | |||
| 19:40 UTC | 170° 29 kt | 34 | 991.2 | |||
| 19:45 UTC | 160° 26 kt | 990.9 | ||||
| 19:50 UTC | 170° 24 kt | 990.9 | ||||
| 19:55 UTC | 170° 29 kt | 38 | 990.2 | |||
| 19:56 UTC | 69 | 56 | 170° 29 kt | 38 | 990.2 | |
| 20:00 UTC | 170° 27 kt | 34 | 989.8 | |||
| 20:05 UTC | 160° 22 kt | 30 | 989.8 | |||
| 20:10 UTC | 160° 24 kt | 989.5 | ||||
| 20:15 UTC | 160° 32 kt | 41 | 988.5 | |||
| 20:20 UTC | 160° 28 kt | 988.1 | ||||
| 20:25 UTC | 160° 23 kt | 987.8 | ||||
| 20:30 UTC | 23 kt | 29 | 987.1 | |||
| 20:35 UTC | 160° 21 kt | 987.8 | ||||
| 20:40 UTC | 22 kt | 987.1 | ||||
| 20:45 UTC | 150° 20 kt | 986.8 | ||||
| 20:50 UTC | 150° 18 kt | 986.5 | ||||
| 20:55 UTC | 140° 19 kt | 985.8 | ||||
| 20:56 UTC | 68 | 55 | 150° 19 kt | 24 | 985.8 | VCTS |
| 21:00 UTC | 140° 17 kt | 985.1 | -RA | |||
| 21:05 UTC | 160° 34 kt | RA SQ | ||||
| 21:10 UTC | 200° | 988.5 | RA SQ | |||
| 21:11 UTC | 57.2 | 48.2 | 200° 32 kt | 59 | 988.5 | -TSRA SQ |
| 21:15 UTC | 190° 26 kt | 34 | 988.5 | RA | ||
| 21:20 UTC | 200° 20 kt | 987.8 | -RA | |||
| 21:20 UTC | 51.8 | 46.4 | 200° 20 kt | 39 | 987.8 | -TSRA |
| 21:25 UTC | 200° 17 kt | 988.5 | -RA | |||
| 21:30 UTC | 190° 14 kt | 988.1 | -RA | |||
| 21:35 UTC | 180° 11 kt | 988.1 | -RA | |||
| 21:40 UTC | 190° 11 kt | 988.1 | ||||
| 21:41 UTC | 51.8 | 48.2 | 190° 11 kt | 22 | 988.1 | |
| 21:45 UTC | 170° 14 kt | 988.1 | ||||
| 21:50 UTC | 180° 15 kt | 988.1 | ||||
| 21:55 UTC | 170° 15 kt | 988.5 | -RA | |||
| 21:56 UTC | 51 | 48 | 180° 13 kt | 988.5 | -RA | |
| 22:00 UTC | 180° 13 kt | 988.5 | -RA | |||
| 22:05 UTC | 190° 11 kt | 988.1 | -RA | |||
| 22:10 UTC | 180° 10 kt | 987.8 | ||||
| 22:15 UTC | 180° 11 kt | 987.5 | ||||
| 22:20 UTC | 180° 13 kt | 987.8 | ||||
| 22:25 UTC | 180° 11 kt | 987.8 | ||||
| 22:30 UTC | 170° 14 kt | 987.8 | ||||
| 22:35 UTC | 170° 11 kt | 987.5 | ||||
| 22:40 UTC | 180° 11 kt | 987.5 | ||||
| 22:45 UTC | 180° 11 kt | 987.5 | ||||
| 22:50 UTC | 170° 11 kt | 987.5 | ||||
| 22:55 UTC | 170° 11 kt | 987.1 | ||||
| 22:56 UTC | 53 | 49 | 180° 11 kt | 987.1 | ||
| 23:00 UTC | 180° 10 kt | 987.1 |
From the Iowa Environmental Mesonet's archive of airport observations.
The radar
The Omaha radar (KOAX), 85 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.
What was reported nearby
Local storm reports within 60 km of the path, in the three hours either side.
| Time (UTC) | Report | Where | County | Remark |
|---|---|---|---|---|
| 20:29 UTC | TSTM WND GST 60 | 6 Wnw Fullerton | Nance, NE | |
| 20:30 UTC | TORNADO | 3 Sse Hordville | Hamilton, NE | NWS DAMAGE SURVEY FOUND PRELIMINARY EF-1 DAMAGE FROM A TORNADO THAT TRACKED FROM ROUGHLY 7 SSW OF HORDVILLE TO 2 N OF POLK. ADDITIONAL INFORMATION WILL BE ADDED ONCE SURVEY IS COMPLETE. |
| 20:31 UTC | TSTM WND DMG | 3 Se Hordville | Hamilton, NE | IRRIGATION PIVOTS OVERTURNED IN THE AREA OF 25 AND X ROAD. POSSIBLE TORNADO DAMAGE BUT UNCONFIRMED AT THIS TIME. TIME ESTIMATED FROM RADAR. |
| 20:34 UTC | TSTM WND DMG | 1 N Fullerton | Nance, NE | DELAYED REPORT VIA TWITTER. COMPLETE LOSS OF ROOF OF SHED. SMALL OUTBUILDING DESTROYED. TIME ESTIMATED FROM RADAR. |
| 20:36 UTC | TSTM WND DMG | 2 E Polk | Polk, NE | DAMAGE REPORTED ALONG AND NEAR HIGHWAY 66 FROM 2 TO 4 MILES EAST OF POLK. MAINLY NUMEROUS IRRIGATION PIVOTS AND A FEW OUTBUILDINGS. TIME ESTIMATED FROM RADAR DATA. UNKNOWN IF TORNADO DAMAGE. |
| 20:40 UTC | TORNADO | 4 Ne Polk | Polk, NE | NWS DAMAGE SURVEY FOUND PRELIMINARY EF-1 DAMAGE FROM A TORNADO THAT TRACKED FROM ROUGHLY 2 SE OF POLK TO 6 W OF OSCEOLA. ADDITIONAL INFORMATION WILL BE ADDED ONCE SURVEY IS COMPLETE. |
| 20:48 UTC | TSTM WND GST 60 | Osceola | Polk, NE | PEA SIZED HAIL WITH 60-70MPH WINDS. |
| 20:50 UTC | TSTM WND DMG | Columbus | Platte, NE | ROOF BLOWN OFF HOME. |
| 20:52 UTC | TSTM WND GST 58 | 1 W Stromsburg | Polk, NE | |
| 20:52 UTC | TSTM WND DMG | Columbus | Platte, NE | OVERTURNED 5TH WHEEL TRAILER. |
| 21:00 UTC | TSTM WND GST 60 | 1 Ne Gresham | York, NE | |
| 21:01 UTC | TSTM WND DMG | Columbus | Platte, NE | ROOF TORN OFF HOME. |
| 21:03 UTC | TORNADO | 1 S Platte Center | Platte, NE | 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 A |
| 21:04 UTC | HAIL 1.25 | Columbus | Platte, NE | |
| 21:04 UTC | TORNADO 1 | Columbus | Platte, NE | EMERGENCY MANAGEMENT REPORTS ROOF OFF HOUSE AFTER BRIEF TORNADO SPIN-UP. |
| 21:04 UTC | TORNADO | Columbus | Platte, NE | *** 2 INJ *** UPDATES PREVIOUS TORNADO REPORT FROM COLUMBUS. 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 |
| 21:04 UTC | TORNADO | Columbus | Platte, NE | UPDATES PREVIOUS TORNADO REPORT FROM COLUMBUS. 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 T |
| 21:04 UTC | TORNADO | Columbus | Platte, NE | CORRECTS PREVIOUS TORNADO REPORT FROM COLUMBUS. EMERGENCY MANAGEMENT REPORTS ROOF OFF HOUSE AFTER BRIEF TORNADO SPIN-UP. |
| 21:04 UTC | TORNADO | Columbus | Platte, NE | EMERGENCY MANAGEMENT REPORTS ROOF OFF HOUSE AFTER BRIEF TORNADO SPIN-UP. |
| 21:05 UTC | HAIL 1.25 | Columbus | Platte, NE | |
| 21:05 UTC | NON-TSTM WND GST 68 | 2 Ene Columbus | Platte, NE | AWOS STATION KOLU COLUMBUS AIRPORT. |
| 21:06 UTC | NON-TSTM WND GST 51 | 4 Wsw Columbus | Platte, NE | MESONET STATION UP939 3.8 W COLUMBUS (UPR). |
| 21:07 UTC | NON-TSTM WND GST 58 | 2 Wnw Columbus | Platte, NE | MESONET STATION DW9727 COLUMBUS. |
| 21:13 UTC | TORNADO | 2 Se Humphrey | Platte, NE | TORNADO ON THE GROUND. |
| 21:14 UTC | TSTM WND GST 68 | 1 Nne Columbus | Platte, NE | |
| 21:15 UTC | TSTM WND GST 84 | 2 Ne David City | Butler, NE | FROM PERSONAL WEATHER STATION. |
| 21:17 UTC | TSTM WND DMG | Schuyler | Colfax, NE | LARGE TREE DOWN IN FRONT YARD. PICTURE RECEIVED VIA TWITTER. REPORT TIME BASED ON RADAR. |
| 21:19 UTC | TSTM WND GST 59 | 3 W Schuyler | Colfax, NE | MESONET STATION UP948 2.5 W SCHUYLER (UPR). |
| 21:20 UTC | TSTM WND GST 53 | 1 Wnw Leigh | Platte, NE | MESONET STATION NB069 LEIGH 1W. |
| 21:27 UTC | TSTM WND GST 76 | Howells | Colfax, NE | WIND GUST TO 76 MPH ALONG WITH PENNY SIZED HAIL. |
| 21:27 UTC | TORNADO | Howells | Colfax, NE | AN INTERMITTENT TORNADO TRACKED FROM NORTH TO SOUTH THROUGH HOWELLS. THE INITIAL DAMAGE POINT WAS ROOF DAMAGE TO A HOME ON THE SOUTH SIDE OF TOWN ALONG WITH MODERATE TREE DAMAGE. THE TORNADO THEN SKIPPED SEVERAL BLOCKS B |
| 21:31 UTC | TORNADO | 3 Nne Howells | Cuming, NE | 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 OPE |
| 21:35 UTC | TSTM WND DMG | Howells | Colfax, NE | PARTIAL ROOF BLOWN OFF. |
| 21:37 UTC | TORNADO | 5 Nnw Snyder | Cuming, NE | AN INTERMITTENT PATH OF DAMAGE ACROSS OPEN FIELDS BUT SNAPPED OFF POWER POLES IN MULTIPLE LOCATIONS, AND ALSO CAUSED ROOF DAMAGE TO A SHED. |
| 21:37 UTC | TORNADO | 6 W West Point | Cuming, NE | 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. |
From the Iowa Environmental Mesonet's archive of National Weather Service local storm reports.
This ground now
The live radar over the trackEvery 2021 tornado in NebraskaEvery tornado in Nebraska since 1950Warnings in force in Nebraska nowThe forecast where you are
The other tornadoes of December 15, 2021
124 more were confirmed in the United States that day.
| Date | Time | Rating | Where | Path (mi) | Width (yd) | Deaths | Injuries | Damage |
|---|---|---|---|---|---|---|---|---|
| December 15 | 1:27 PM CST | EF0 | Kearney, NE | 11.0 | 150 | $700,000 | ||
| December 15 | 1:29 PM CST | EF0 | Franklin, NE | 13.4 | 100 | $700,000 | ||
| December 15 | 1:33 PM CST | EF0 | Kearney, NE | 7.1 | 120 | $350,000 | ||
| December 15 | 1:44 PM CST | EF1 | Webster, NE | 14.8 | 180 | $400,000 | ||
| December 15 | 1:53 PM CST | EF1 | Adams, NE | 8.6 | 150 | $400,000 | ||
| December 15 | 2:03 PM CST | EF0 | Adams, NE | 7.2 | 60 | $302,000 | ||
| December 15 | 2:11 PM CST | EF1 | Hamilton, NE | 12.9 | 400 | $500,000 | ||
| December 15 | 2:26 PM CST | EF1 | Hamilton, NE | 12.0 | 400 | $500,000 | ||
| December 15 | 2:35 PM CST | EF1 | Polk, NE | 7.5 | 350 | $400,000 | ||
| December 15 | 3:03 PM CST | EF1 | Platte, NE | 0.8 | 30 | |||
| December 15 | 3:11 PM CST | EF2 | Saline, NE | 23.7 | 70 | |||
| December 15 | 3:27 PM CST | EF1 | Colfax, NE | 1.5 | 30 | |||
| December 15 | 3:31 PM CST | EF2 | Cuming, NE | 6.3 | 100 | |||
| December 15 | 3:37 PM CST | EF1 | Cuming, NE | 4.8 | 50 | |||
| December 15 | 3:37 PM CST | EF1 | Cuming, NE | 1.8 | 50 | |||
| December 15 | 3:41 PM CST | EF1 | Cuming, NE | 0.4 | 50 | |||
| December 15 | 3:41 PM CST | EF1 | Saunders, NE | 16.6 | 100 | |||
| December 15 | 3:44 PM CST | EF2 | Cuming, NE | 11.2 | 200 | |||
| December 15 | 3:46 PM CST | EF1 | Saunders, NE | 0.7 | 100 | |||
| December 15 | 3:51 PM CST | EF1 | Cuming, NE | 11.2 | 20 | |||
| December 15 | 3:55 PM CST | EF2 | Cass, NE | 3.3 | 20 | |||
| December 15 | 4:05 PM CST | EF1 | Otoe, NE | 0.1 | 200 | |||
| December 15 | 4:05 PM CST | EF1 | Pawnee, NE | 0.2 | 20 | |||
| December 15 | 4:06 PM CST | EF0 | Pawnee, NE | 2.2 | 20 | |||
| December 15 | 4:06 PM CST | EF2 | Cass, NE | 3.6 | 150 | |||
| December 15 | 4:07 PM CST | EF1 | Pawnee, NE | 0.8 | 100 | |||
| December 15 | 4:09 PM CST | EF2 | Cass, NE | 2.6 | 200 | |||
| December 15 | 4:14 PM CST | EF1 | Mills, IA | 10.0 | 100 | |||
| December 15 | 4:15 PM CST | Unrated | Woodbury, IA | 0.8 | 20 | |||
| December 15 | 4:16 PM CST | EF0 | Pottawattamie, IA | 0.9 | 30 | |||
| December 15 | 4:20 PM CST | EF1 | Woodbury, IA | 4.6 | 75 | $250,000 | ||
| December 15 | 4:24 PM CST | EF2 | Pottawattamie, IA | 2.3 | 50 | |||
| December 15 | 4:25 PM CST | EF2 | Woodbury, IA | 8.4 | 100 | $500,000 | ||
| December 15 | 4:31 PM CST | EF1 | Mills, IA | 0.6 | 50 | |||
| December 15 | 4:31 PM CST | EF2 | Pottawattamie, IA | 6.7 | 75 | |||
| December 15 | 4:34 PM CST | EF1 | Pottawattamie, IA | 9.6 | 50 | |||
| December 15 | 4:35 PM CST | EF1 | Woodbury, IA | 4.3 | 75 | $200,000 | ||
| December 15 | 4:39 PM CST | EF1 | Plymouth, IA | 3.7 | 75 | $50,000 | ||
| December 15 | 4:42 PM CST | EF1 | Ida, IA | 13.0 | 75 | $200,000 | ||
| December 15 | 4:48 PM CST | Unrated | Crawford, IA | 4.4 | 50 | |||
| December 15 | 4:49 PM CST | EF2 | Cass, IA | 27.1 | 100 | $350,000 | ||
| December 15 | 4:58 PM CST | EF0 | Ida, IA | 2.9 | 50 | $75,000 | ||
| December 15 | 4:59 PM CST | EF1 | Cherokee, IA | 11.2 | 250 | $1.0 million | ||
| December 15 | 5:00 PM CST | Unrated | Cherokee, IA | 1.8 | 50 | |||
| December 15 | 5:00 PM CST | EF1 | Cass, IA | 11.4 | 80 | $100,000 | ||
| December 15 | 5:01 PM CST | EF1 | Buena Vista, IA | 6.4 | 75 | $200,000 | ||
| December 15 | 5:05 PM CST | EF1 | Cherokee, IA | 3.8 | 75 | $250,000 | ||
| December 15 | 5:07 PM CST | EF1 | Buena Vista, IA | 6.9 | 150 | $100,000 | ||
| December 15 | 5:08 PM CST | EF1 | O'Brien, IA | 3.9 | 100 | $50,000 | ||
| December 15 | 5:10 PM CST | EF1 | Guthrie, IA | 11.4 | 70 | $100,000 | ||
| December 15 | 5:13 PM CST | EF2 | Sac, IA | 17.6 | 100 | $150,000 | ||
| December 15 | 5:14 PM CST | EF2 | Guthrie, IA | 19.7 | 100 | $450,000 | ||
| December 15 | 5:18 PM CST | EF2 | Buena Vista, IA | 4.8 | 100 | $250,000 | ||
| December 15 | 5:19 PM CST | EF1 | Carroll, IA | 9.7 | 80 | $80,000 | ||
| December 15 | 5:21 PM CST | EF2 | Guthrie, IA | 30.0 | 300 | $470,000 | ||
| December 15 | 5:27 PM CST | EF2 | Guthrie, IA | 23.4 | 150 | $801,000 | ||
| December 15 | 5:29 PM CST | EF2 | Greene, IA | 5.5 | 100 | $1.2 million | ||
| December 15 | 5:32 PM CST | EF2 | Greene, IA | 5.8 | 100 | $500,000 | ||
| December 15 | 5:34 PM CST | Unrated | Calhoun, IA | 1.3 | 40 | |||
| December 15 | 5:34 PM CST | EF2 | Greene, IA | 2.7 | 70 | $20,000 |
What this means
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.
Sources
NOAA Storm Prediction Center tornado database, 1950-2025, the official record kept by NOAA's Storm Prediction Center.