Tornadoes · United States · Iowa · 2021

EF0 tornado, Beverly, Iowa, April 7, 2021

This EF0 tornado ran 0.7 miles across Linn County on April 7, 2021, touching down at 8:36 PM CDT and reaching 40 yards wide. It killed nobody and injured 1.

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.

  1. EF065 to 85 mphthis tornado

    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. 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
EF0
Date
April 7, 2021
Touchdown
8:36 PM CDT (01:36 UTC)
Lifted
8:37 PM CDT (01:37 UTC)
On the ground
1 minutes
Path length
0.7 miles (1.0 km)
Path width
40 yards (37 m)
Deaths
0
Injuries
1
County
Linn County
Touchdown point
41.956, -91.740
Lift-off point
41.948, -91.732
Record number
2104071936-01

The damage survey

5 damage points were recorded along this path by NWS DVN, in the Damage Assessment Toolkit the survey teams carry. The strongest indicator was rated EF0. The highest wind the damage implies is 85 mph.

  • roof of large garage peeled back

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 slowly moving storm system brought several rounds of showers and thunderstorms to eastern Iowa, northwest Illinois and far northeast Missouri during the day on Wednesday April 7, 2021. The heavy rainfall occurred south of a Fairfield to Galesburg line with reports ranging from 1.13 inches in Burlington to 1.80 inches in Bushnell Illinois. A few of these thunderstorms became severe and produced damaging winds in McDonough, Henderson, and Hancock Counties during the late afternoon and early evening hours. Damage was also reported to some mobile homes and a garage on the southwest side of Cedar Rapids due to a weak tornado that caused one minor injury due to glass from a broken window.

A brief tornado caused damage to several manufactured homes and a garage in the southwest part of Cedar Rapids Wednesday evening. One home sustained significant roof damage, with additional siding damage to nearby homes. One person sustained minor injuries from glass after their bedroom window blew in. The tornado lofted debris into a nearby field. Maximum sustained winds were around 85 mph and the tornado was rated EF-0.

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

The warnings

No tornado warning for this county appears in the archive as in force at the moment the tornado touched down.

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 Marginal Risk. The outlook in force was issued at 00:33 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.

Davenport, (KDVN), 00:00Z

1.6 hours before the tornado, 109 km from the path. April 8, 2021.

Skew-T log-pSkew-T log-p diagram, Davenport, at 00:00Z on 2021-04-08Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 305 joules per kilogram, CIN -65, lifted condensation level 927 meters above ground. Wind barbs in knots down the right edge.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed. The warm shading is its CAPE, the cool shading the inhibition it has to break through.
HodographHodograph, Davenport, at 00:00Z on 2021-04-08The wind through the lowest 10 kilometers as a curve, rings every 10 meters per second labeled in knots. Zero to 1 km storm-relative helicity 182 square meters per square second, 0 to 6 km bulk shear 29 knots.193958Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km. RM and LM are the right and left moving storms Bunkers' method gives; the shaded area is the 0 to 1 km storm-relative helicity.
Mixed-layer CAPE
305 J/kg
Mixed-layer CIN
-65 J/kg
Surface CAPE
452 J/kg
Mixed-layer LCL
927 m above ground
0-6 km bulk shear
29 kt
0-1 km bulk shear
26 kt
0-1 km storm-relative helicity
182 m²/s²
0-3 km storm-relative helicity
140 m²/s²
Significant tornado parameter
0.2
Supercell composite
1.1
0-3 km lapse rate
6.1 K/km

Open this sounding in Storm Lab

Davenport, (KDVN), 12:00Z

10.4 hours after it, 109 km from the path. April 8, 2021.

Skew-T log-pSkew-T log-p diagram, Davenport, at 12:00Z on 2021-04-08Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 0 joules per kilogram, CIN -57075, lifted condensation level 743 meters above ground. Wind barbs in knots down the right edge.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed. The warm shading is its CAPE, the cool shading the inhibition it has to break through.
HodographHodograph, Davenport, at 12:00Z on 2021-04-08The wind through the lowest 10 kilometers as a curve, rings every 10 meters per second labeled in knots. Zero to 1 km storm-relative helicity -6 square meters per square second, 0 to 6 km bulk shear 57 knots.1939587897Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km. RM and LM are the right and left moving storms Bunkers' method gives; the shaded area is the 0 to 1 km storm-relative helicity.
Mixed-layer CAPE
0 J/kg
Mixed-layer CIN
-57075 J/kg
Surface CAPE
12 J/kg
Mixed-layer LCL
743 m above ground
0-6 km bulk shear
57 kt
0-1 km bulk shear
28 kt
0-1 km storm-relative helicity
-6 m²/s²
0-3 km storm-relative helicity
0 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0
0-3 km lapse rate
4.3 K/km

Open this sounding in Storm Lab

The radar

The Quad Cities radar (KDVN), 103 km away, was scanning. The volume nearest the touchdown began at 01:33 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)ReportWhereCountyRemark
01:30 UTCTSTM WND DMG3 Ne FairfaxLinn, IAREPORTS OF DAMAGE TO SOME MOBILE HOMES. WINDOWS BLOWN OUT, SIDING RIPPED OFF THE HOUSE, PART OF THE ROOF BLOWN OFF, ALONG WITH MANY SHINGLES BLOWN OFF THE ROOF. TORNADO POSSIBLE.
01:36 UTCTORNADO3 Ne FairfaxLinn, IACORRECTS PREVIOUS TORNADO REPORT TO CHANGE THE TIME FROM AM TO PM 3 NE FAIRFAX. A BRIEF TORNADO CAUSED DAMAGE TO SEVERAL MANUFACTURED HOMES IN THE SOUTHWEST PART OF CEDAR RAPIDS WEDNESDAY EVENING. ONE HOME SUSTAINED SIGN

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 IowaEvery tornado in Iowa since 1950Warnings in force in Iowa nowThe forecast where you are

The other tornadoes of April 7, 2021

10 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
April 74:33 PM CDTEF1Bossier Parish, LA0.950$10,000
April 74:35 PM CDTEF1Red River Parish, LA13.3300$50,000
April 76:48 PM CDTEF0Ouachita Parish, LA2.850
April 77:30 PM CDTEF1Morehouse Parish, LA8.2751$250,000
April 78:06 PM CDTEF1Morehouse Parish, LA2.7200$150,000
April 78:16 PM CDTEF1West Carroll Parish, LA to AR9.250$500,000
April 78:24 PM CDTEF0Chicot, AR2.650$30,000
April 79:13 PM CDTEF1Rapides Parish, LA0.9200$30,000
April 79:52 PM CDTEF1Avoyelles Parish, LA1.8200$250,000
April 710:16 PM CDTEF1Avoyelles Parish, LA3.4200$100,000

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.