Tornadoes · United States · Colorado · 2018

EF0 tornado, Coalmont, Colorado, June 24, 2018

This EF0 tornado ran 0.0 miles across Jackson County on June 24, 2018, touching down at 11:14 AM MDT and reaching 50 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 24, 2018
Touchdown
11:14 AM MDT (17:14 UTC)
Lifted
11:15 AM MDT (17:15 UTC)
On the ground
1 minutes
Path length
0.0 miles (0.0 km)
Path width
50 yards (46 m)
Deaths
0
Injuries
0
County
Jackson County
Touchdown point
40.540, -106.500
Lift-off point
40.540, -106.500
Record number
1806241114-01

What the Weather Service recorded

A tornado briefly touched down approximately 19 miles southwest of Walden. No damage has been reported. This is only the third documented tornado in Jackson County since 1950. The first reported tornado was May 10th 1974. Severe thunderstorms produced hail up to quarter size in Lincoln and Weld counties.

A tornado touched down briefly in open country. No damage was observed.

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 General Thunderstorms Risk. The outlook in force was issued at 16:31 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.

Grand Junction, CO (KGJT), 12:00Z

5.2 hours before the tornado, 232 km from the path. June 24, 2018.

Skew-T log-pSkew-T log-p diagram, Grand Junction, CO at 12:00Z on 2018-06-24Temperature 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 -75299, lifted condensation level 2972 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, Grand Junction, CO at 12:00Z on 2018-06-24The 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 -68 square meters per square second, 0 to 6 km bulk shear 52 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
-75299 J/kg
Surface CAPE
0 J/kg
Mixed-layer LCL
2972 m above ground
0-6 km bulk shear
52 kt
0-1 km bulk shear
15 kt
0-1 km storm-relative helicity
-68 m²/s²
0-3 km storm-relative helicity
109 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0
0-3 km lapse rate
6.9 K/km

Open this sounding in Storm Lab

Grand Junction, CO (KGJT), 00:00Z

6.8 hours after it, 232 km from the path. June 25, 2018.

Skew-T log-pSkew-T log-p diagram, Grand Junction, CO at 00:00Z on 2018-06-25Temperature 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 -77504, lifted condensation level 3626 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, Grand Junction, CO at 00:00Z on 2018-06-25The 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 53 square meters per square second, 0 to 6 km bulk shear 43 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
-77504 J/kg
Surface CAPE
0 J/kg
Mixed-layer LCL
3626 m above ground
0-6 km bulk shear
43 kt
0-1 km bulk shear
11 kt
0-1 km storm-relative helicity
53 m²/s²
0-3 km storm-relative helicity
42 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0
0-3 km lapse rate
10.0 K/km

Open this sounding in Storm Lab

The radar

The Cheyenne radar (KCYS), 158 km away, was scanning. The volume nearest the touchdown began at 17:16 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
16:19 UTCTORNADO7 Wsw ClarkRoutt, COCONFIRMED TORNADO WITH ROTATION ON THE GROUND AT ABOUT 8500 FEET FOR ABOUT ONE MINUTE. FUNNEL CLOUD LASTED FOR AT LEAST TEN MINUTES.
17:15 UTCTORNADO4 Wsw CoalmontJackson, COTIME AND LOCATION OF TORNADO ESTIMATED.
17:30 UTCFUNNEL CLOUD5 Wnw Steamboat SpringsRoutt, CONEWS REPORTER SHARED VIDEOS AND IMAGES OF A FUNNEL CLOUD NORTHWEST OF STEAMBOAT SPRINGS AROUND 11:30 AM. NO IMAGES OR REPORTS HAD THE FUNNEL CLOUD REACHING THE GROUND. RADAR IMAGERY SHOWED ROTATION.
17:30 UTCHAIL 0.753 Nw Steamboat SpringsRoutt, COIMAGES SHOWED HAIL WEST OF STEAMBOAT SPRINGS FROM A THUNDERSTORM THAT MOVED THROUGH THE AREA AROUND 11:30 AM. PICTURES SHOWED HAIL SIZED FROM PEA TO PENNY SIZED.

From the Iowa Environmental Mesonet's archive of National Weather Service local storm reports.

This ground now

The live radar over the trackEvery 2018 tornado in ColoradoEvery tornado in Colorado since 1950Warnings in force in Colorado nowThe forecast where you are

The other tornadoes of June 24, 2018

8 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
June 2410:18 AM MDTEF0Routt, CO0.330
June 243:12 PM CDTEF0Pontotoc, OK0.210$1,000
June 243:51 PM CDTEF0Lincoln, MN0.450
June 245:10 PM CDTEF0Roberts, SD0.05
June 247:12 PM CDTEF0Fillmore, NE0.125
June 247:14 PM CDTEF0Fillmore, NE0.735
June 247:17 PM CDTEF0Fillmore, NE0.225
June 247:43 PM CDTEF0Fillmore, NE0.735

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.