Tornadoes · United States · Iowa · 2021

EF1 tornado, Langworthy to Temple Hill, Iowa, July 14, 2021

From Langworthy to Temple Hill, this EF1 tornado ran 1.8 miles across Jones County on July 14, 2021, touching down at 9:44 PM CDT and reaching 40 yards wide. It killed nobody.

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 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.

The record

Rating
EF1
Date
July 14, 2021
Touchdown
9:44 PM CDT (02:44 UTC)
Lifted
9:48 PM CDT (02:48 UTC)
On the ground
4 minutes
Path length
1.8 miles (2.9 km)
Path width
40 yards (37 m)
Deaths
0
Injuries
0
County
Jones County
Touchdown point
42.210, -91.290
Lift-off point
42.209, -91.258
Record number
2107142044-01

The damage survey

11 damage points were recorded along this path by NWS DVN, in the Damage Assessment Toolkit the survey teams carry. The strongest indicator was rated EF1. The highest wind the damage implies is 110 mph.

  • 6114 Richland Road old barn roof gone
  • Large tree snapped at base, several other large limbs lying around. Facing east
  • Hay bale is starting point, about 0.5 miles southwest
  • Some metal paneling missing. Section of roof missing

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

Severe thunderstorms developed ahead of an approaching cold front during the afternoon and evening of Wednesday, July 14. Some of the storms produced damaging winds and several tornadoes, most of which only briefly touched down. Brief torrential rainfall was also observed with the stronger storm cells. The areas that were hit hardest were in Delaware and Jones counties in IA, where a total of 5 tornadoes occurred. An additional 7 tornadoes touched down in eastern IA, with no visible damage reported.

An EF-1 tornado touched down southwest of Monticello damaging outbuildings and snapping large trees on two farmsteads.

An EF-1 tornado developed southeast of Monticello and tracked across rural areas east of Monticello along an intermittent 8 mile path through farmland and wooded areas.

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

The warnings

15 minutes of warning. NWS DVN issued a tornado warning for this county at 02:29 UTC, 15 minutes before the tornado touched down, in force until 03:15 UTC.

The county was under a tornado watch, issued at 23:14 UTC and running to 04:21 UTC.

Issued (UTC)ExpiredProductOffice
23:14 UTC04:21 UTCTornado WatchDVN
02:29 UTC03:15 UTCTornado WarningDVN
03:02 UTC03:45 UTCTornado WarningDVN
03:14 UTC04:00 UTCSevere Thunderstorm WarningDVN
03:52 UTC04:03 UTCSevere Thunderstorm WarningDVN

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 00:52 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

2.7 hours before the tornado, 92 km from the path. July 15, 2021.

Skew-T log-pSkew-T log-p diagram, Davenport, at 00:00Z on 2021-07-15Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 2569 joules per kilogram, CIN -10, lifted condensation level 832 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 2021-07-15The 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 253 square meters per square second, 0 to 6 km bulk shear 38 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
2569 J/kg
Mixed-layer CIN
-10 J/kg
Surface CAPE
4127 J/kg
Mixed-layer LCL
832 m above ground
0-6 km bulk shear
38 kt
0-1 km bulk shear
30 kt
0-1 km storm-relative helicity
253 m²/s²
0-3 km storm-relative helicity
346 m²/s²
Significant tornado parameter
3.2
Supercell composite
23.4
0-3 km lapse rate
6.4 K/km

Open this sounding in Storm Lab

Davenport, (KDVN), 12:00Z

9.3 hours after it, 92 km from the path. July 15, 2021.

Skew-T log-pSkew-T log-p diagram, Davenport, at 12:00Z on 2021-07-15Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 78 joules per kilogram, CIN -116, lifted condensation level 688 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 12:00Z on 2021-07-15The 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 106 square meters per square second, 0 to 6 km bulk shear 27 knots.19395878Sfc1 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
78 J/kg
Mixed-layer CIN
-116 J/kg
Surface CAPE
177 J/kg
Mixed-layer LCL
688 m above ground
0-6 km bulk shear
27 kt
0-1 km bulk shear
19 kt
0-1 km storm-relative helicity
106 m²/s²
0-3 km storm-relative helicity
80 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.1
0-3 km lapse rate
4.5 K/km

Open this sounding in Storm Lab

The radar

The Quad Cities radar (KDVN), 88 km away, was scanning. The volume nearest the touchdown began at 02:41 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.

What was reported nearby

Local storm reports within 60 km of the path, in the three hours either side.

Time (UTC)ReportWhereCountyRemark
00:05 UTCFUNNEL CLOUD1.3 Sw AuroraBuchanan, IAREPORTED VIA EM.
00:10 UTCTORNADO3 Sse AuroraBuchanan, IABRIEF TOUCHDOWN IN A FIELD WITH NO VISIBLE DAMAGE.
00:52 UTCTORNADO3 Ssw Manchester AirporDelaware, IATORNADO REPORTED ON THE GROUND SOUTH OF HIGHWAY 20 SOUTHWEST OF MANCHESTER.
00:53 UTCTORNADO1 Sw ManchesterDelaware, IADELAWARE COUNTY EMA RELAYED LIKELY TORNADO DAMAGE REPORT OF A DAMAGED CONVENIENCE STORE AND POWER LINES DOWN ON SOUTHWEST SIDE OF MANCHESTER.
00:58 UTCTORNADOManchesterDelaware, IASPOTTERS REPORTING TWO SEPARATE TORNADOES, ONE ABOUT TO CROSS HIGHWAY 13, NORTH OF HIGHWAY 20 NEAR MANCHESTER AND THE OTHER ABOUT 3 MILES WEST OF MANCHESTER.
01:20 UTCFUNNEL CLOUDPaloLinn, IARELAYED VIA LINN COUNTY EMA.
01:30 UTCFUNNEL CLOUD3 Sw Center PointLinn, IAFUNNEL CLOUD EXTENDING HALF WAY TO THE GROUND.
01:40 UTCHEAVY RAIN 2.43Strawberry PointClayton, IA
01:46 UTCTORNADO4 Nne LafayetteLinn, IABRIEF TORNADO. DELAYED REPORT FROM EMERGENCY MANAGER.
01:50 UTCTSTM WND DMG3 Nnw Center PointLinn, IALARGE AREA OF FLATTENED CORN.
01:50 UTCTORNADO4 Nne LafayetteLinn, IABRIEF TOUCHDOWN IN A FIELD WITH NO VISIBLE DAMAGE.
01:52 UTCTORNADO3 N Center PointLinn, IABRIEF TOUCHDOWN IN A FIELD WITH NO VISIBLE DAMAGE.
01:55 UTCFUNNEL CLOUD3 Sw ParisLinn, IABROAD ROTATING FUNNEL CLOUD EXTENDING HALF WAY DOWN FROM CLOUD BASE.
02:10 UTCFUNNEL CLOUDParisLinn, IARELAYING SPOTTER REPORT OF FUNNEL CLOUD CLOSE TO GROUND ALONG PARIS ROAD. DARKNESS MAKING IT DIFFICULT TO SEE IF IT IS REACHING THE GROUND.
02:26 UTCHEAVY RAIN 2.9WalkerLinn, IA
02:44 UTCTORNADO4 Wnw LangworthyJones, IAAN EF-1 TORNADO TOUCHED DOWN SOUTHWEST OF MONTICELLO DAMAGING OUTBUILDINGS AND SNAPPING LARGE TREES ON TWO FARMSTEADS.
02:45 UTCTSTM WND DMG2 Sse Buck CreekDelaware, IADELAYED REPORT. LONG-TRACKED 30 FOOT WIDE SWATH OF CORN FLATTENED ACROSS FIELD. POSSIBLY DUE TO TORNADO. TIME ESTIMATED FROM SPOTTER OBSERVATION AND RADAR.
02:50 UTCTSTM WND DMG4 Nw LangworthyJones, IADAMAGE TO HOME AND MACHINE SHED. REPORT RELAYED BY EM. POSSIBLE TORNADO. TIME ESTIMATED FROM RADAR.
03:02 UTCTORNADO2 Sse Monticello MuniciJones, IAAN EF-1 TORNADO DEVELOPED SOUTHEAST OF MONTICELLO AND TRACKED ACROSS RURAL AREAS EAST OF MONTICELLO ALONG AN INTERMITTENT 8 MILE PATH THROUGH FARMLAND AND WOODED AREAS.
03:30 UTCTORNADO3 Wsw CantonJones, IAAN EF-1 TORNADO TRACKED ACROSS RURAL JONES COUNTY SNAPPING TREES AND ENDING JUST SOUTH OF CANTON.
03:33 UTCTSTM WND GST 602 Ne BuchananCedar, IACOUNTY OFFICIAL REPORTED ESTIMATED WIND GUSTS OF UP TO 60 MPH GENERALLY 6 MILES WEST OF THE TIPTON AREA.

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 July 14, 2021

25 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
July 143:52 PM CDTEF3Calhoun, IA10.8505$2.5 million
July 144:05 PM CDTEF0Hamilton, IA8.850$2,000
July 144:21 PM CDTEF1Hamilton, IA8.9160$10,000
July 144:46 PM CDTUnratedWebster, IA0.330
July 144:57 PM CDTUnratedButler, IA1.250
July 145:11 PM CDTUnratedSac, IA0.625
July 145:16 PM CDTEF2Butler, IA12.9630$1.3 million
July 145:34 PM CDTEF1Floyd, IA12.060$60,000
July 145:35 PM CDTUnratedSac, IA0.830
July 145:52 PM CDTEF0Cerro Gordo, IA5.1225$10,000
July 146:12 PM CDTEF0Bremer, IA2.5150$1,000
July 145:15 PM MDTUnratedEmery, UT0.110
July 146:43 PM CDTEF0Buchanan, IA3.230$275,000
July 147:05 PM CDTEF1Tama, IA5.7590$25,000
July 147:10 PM CDTUnratedBuchanan, IA0.110
July 147:36 PM CDTUnratedBenton, IA0.110
July 147:50 PM CDTEF1Delaware, IA1.440
July 147:54 PM CDTEF1Delaware, IA1.130
July 147:56 PM CDTUnratedBenton, IA0.110
July 148:07 PM CDTUnratedBenton, IA0.110
July 148:50 PM CDTUnratedLinn, IA0.110
July 148:52 PM CDTUnratedLinn, IA0.110
July 149:40 PM CDTUnratedDelaware, IA0.410
July 1410:02 PM CDTEF1Jones, IA8.030
July 1410:30 PM CDTEF1Jones, IA3.130

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.