Tornadoes · United States · Colorado · 2021

EF0 tornado, Leader, Colorado, June 19, 2021

This EF0 tornado ran 0.0 miles across Adams County on June 19, 2021, touching down at 2:34 PM MDT and reaching 25 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 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
June 19, 2021
Touchdown
2:34 PM MDT (20:34 UTC)
Lifted
2:35 PM MDT (20:35 UTC)
On the ground
1 minutes
Path length
0.0 miles (0.0 km)
Path width
25 yards (23 m)
Deaths
0
Injuries
0
County
Adams County
Touchdown point
39.970, -104.000
Lift-off point
39.970, -104.000
Record number
2106191434-01

What the Weather Service recorded

Severe thunderstorms produced several short-lived landspouts, large hail, damaging winds. Five landspouts, all rated EF-0, touched down briefly in portions of eastern Adams and Morgan Counties. Large hail, up to half dollar size, was observed in eastern Adams, Logan, and Washington counties. Intense thunderstorm winds, ranging from 60 to 80 mph, were reported in northern Lincoln, western Logan, and southeastern Washington counties. The winds downed a power line along Logan County Road 34, north of Sterling. Minor tree damage was observed in northeast Lincoln County.

A landspout touched down briefly in an open field. No damage was observed.

A landspout touched down briefly in an open field. No damage was observed.

A landspout touched down briefly in an open field. No damage was observed.

A landspout touched down briefly in an open field. No damage was observed.

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

The warnings

25 minutes of warning. NWS BOU issued a tornado warning for this county at 20:09 UTC, 25 minutes before the tornado touched down, in force until 20:45 UTC.

The county was under a severe thunderstorm watch, issued at 19:45 UTC and running to 23:56 UTC.

Issued (UTC)ExpiredProductOffice
19:45 UTC23:56 UTCSevere Thunderstorm WatchBOU
20:09 UTC20:45 UTCTornado WarningBOU
20:52 UTC21:15 UTCTornado WarningBOU
21:26 UTC22:00 UTCSevere Thunderstorm WarningBOU

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 19:51 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.

Denver, CO (KDNR), 12:00Z

8.6 hours before the tornado, 67 km from the path. June 19, 2021.

Skew-T log-pSkew-T log-p diagram, Denver, CO at 12:00Z on 2021-06-19Temperature 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 -73205, lifted condensation level 2627 meters above ground. Wind barbs in knots down the right edge.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°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, Denver, CO at 12:00Z on 2021-06-19The 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 -23 square meters per square second, 0 to 6 km bulk shear 16 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
0 J/kg
Mixed-layer CIN
-73205 J/kg
Surface CAPE
0 J/kg
Mixed-layer LCL
2627 m above ground
0-6 km bulk shear
16 kt
0-1 km bulk shear
7 kt
0-1 km storm-relative helicity
-23 m²/s²
0-3 km storm-relative helicity
44 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0
0-3 km lapse rate
4.7 K/km

Open this sounding in Storm Lab

Denver, CO (KDNR), 00:00Z

3.4 hours after it, 67 km from the path. June 20, 2021.

Skew-T log-pSkew-T log-p diagram, Denver, CO at 00:00Z on 2021-06-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 112 joules per kilogram, CIN -93, lifted condensation level 2188 meters above ground. Wind barbs in knots down the right edge.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°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, Denver, CO at 00:00Z on 2021-06-20The 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 17 square meters per square second, 0 to 6 km bulk shear 22 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
112 J/kg
Mixed-layer CIN
-93 J/kg
Surface CAPE
880 J/kg
Mixed-layer LCL
2188 m above ground
0-6 km bulk shear
22 kt
0-1 km bulk shear
4 kt
0-1 km storm-relative helicity
17 m²/s²
0-3 km storm-relative helicity
95 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.1
0-3 km lapse rate
7.7 K/km

Open this sounding in Storm Lab

The radar

The Denver radar (KFTG), 51 km away, was scanning. The volume nearest the touchdown began at 20:35 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
20:06 UTCTORNADO1 E LeaderAdams, COFIRST REPORT OF LANDSPOUT. LOCATION ESTIMATED.
20:20 UTCTORNADO2 Ene LeaderAdams, COVIDEO AND PHOTOGRAPHS OF A SECOND TORNADO ON THE GROUND FOR APPROXIMATELY 3 MINUTES, WITH NO VISIBLE FUNNEL ATTACHED TO THE CLOUD BASE. LOCATION ESTIMATED BY RADAR.
20:29 UTCTORNADO6 Ene LeaderAdams, COTHIRD BRIEF LANDSPOUT ON THE GROUND FOR APPROXIMATELY 3 MINUTES. LOCATION ESTIMATED BY RADAR.
20:35 UTCTORNADO5 Se HoytAdams, COLANDSPOUT SOUTHEAST OF HOYT. LOCATION ESTIMATED.
20:44 UTCTORNADO2 W AdenaMorgan, COSEVERAL BRIEF LANDSPOUTS BETWEEN 2:40 AND 2:50 PM.
21:34 UTCHAIL 1.256 Se ShamrockAdams, CO
21:47 UTCHAIL 1.254 W Woodlin SchoolWashington, CODELAYED REPORT. UP TO 1.25 INCH HAIL BETWEEN LAST CHANCE AND WOODROW. TIME AND LOCATION ESTIMATED BY RADAR.

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 ColoradoEvery tornado in Colorado since 1950Warnings in force in Colorado nowThe forecast where you are

The other tornadoes of June 19, 2021

11 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
June 192:31 AM CDTEF0Harrison, MS1.275$50,000
June 193:16 AM CDTEF0Mobile, AL0.1251
June 195:08 AM CDTEF0Jackson, MS0.525$15,000
June 195:35 AM CDTEF1Jackson, MS0.850$5,000
June 197:31 AM CDTEF2Escambia, AL22.065020$3.2 million
June 191:31 PM EDTEF1Early, GA29.0400$3,000
June 191:12 PM CDTEF0Covington, AL0.625
June 192:05 PM MDTEF0Adams, CO0.025
June 192:17 PM MDTEF0Adams, CO0.025
June 192:26 PM MDTEF0Adams, CO0.025
June 192:43 PM MDTEF0Morgan, CO0.025

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.