Tornadoes · United States · Wyoming · 2025

Unrated tornado, Clayton, Wyoming, June 17, 2025

This Unrated tornado ran 0.1 miles across Converse County on June 17, 2025, touching down at 3:03 PM MDT and reaching 10 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 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. Unratedthis tornado

    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
Unrated
Date
June 17, 2025
Touchdown
3:03 PM MDT (21:03 UTC)
Lifted
3:05 PM MDT (21:05 UTC)
On the ground
2 minutes
Path length
0.1 miles (0.2 km)
Path width
10 yards (9 m)
Deaths
0
Injuries
0
County
Converse County
Touchdown point
42.876, -105.782
Lift-off point
42.876, -105.782
Record number
2506171503-01

The damage survey

1 damage points were recorded along this path by NWS CYS, in the Damage Assessment Toolkit the survey teams carry. The strongest indicator was rated EFU.

  • Landspout tornado verified through pictures and reported by emergency management. No damage reported and rated EF-U.

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

Following the nocturnal convection the night/morning of June 16/17, another round of severe storms developed early in the afternoon on June 17. Hail, wind, and tornadoes were reported with these storms.

Photos and video confirmed a landspout near the power plant at Glenrock. No damage was reported.

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.

The county was under a severe thunderstorm watch, issued at 16:49 UTC and running to 00:44 UTC.

Issued (UTC)ExpiredProductOffice
03:57 UTC05:00 UTCSevere Thunderstorm WarningCYS
16:49 UTC00:44 UTCSevere Thunderstorm WatchCYS
21:06 UTC22:00 UTCSevere Thunderstorm WarningCYS
21:43 UTC22:30 UTCSevere Thunderstorm WarningCYS

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 20:00 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.

Riverton, WY (KRIW), 12:00Z

9.1 hours before the tornado, 214 km from the path. June 17, 2025.

Skew-T log-pSkew-T log-p diagram, Riverton, WY at 12:00Z on 2025-06-17Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 1 joules per kilogram, CIN -256, lifted condensation level 1381 meters above ground. Wind barbs in knots down the right edge.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 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, Riverton, WY at 12:00Z on 2025-06-17The 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 -7 square meters per square second, 0 to 6 km bulk shear 42 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
1 J/kg
Mixed-layer CIN
-256 J/kg
Surface CAPE
0 J/kg
Mixed-layer LCL
1381 m above ground
0-6 km bulk shear
42 kt
0-1 km bulk shear
3 kt
0-1 km storm-relative helicity
-7 m²/s²
0-3 km storm-relative helicity
111 m²/s²
Significant tornado parameter
0.0
Supercell composite
-0.0
0-3 km lapse rate
5.3 K/km

Open this sounding in Storm Lab

Riverton, WY (KRIW), 00:00Z

2.9 hours after it, 214 km from the path. June 18, 2025.

Skew-T log-pSkew-T log-p diagram, Riverton, WY at 00:00Z on 2025-06-18Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 105 joules per kilogram, CIN -11, lifted condensation level 2527 meters above ground. Wind barbs in knots down the right edge.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 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, Riverton, WY at 00:00Z on 2025-06-18The 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 75 square meters per square second, 0 to 6 km bulk shear 29 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
105 J/kg
Mixed-layer CIN
-11 J/kg
Surface CAPE
520 J/kg
Mixed-layer LCL
2527 m above ground
0-6 km bulk shear
29 kt
0-1 km bulk shear
19 kt
0-1 km storm-relative helicity
75 m²/s²
0-3 km storm-relative helicity
121 m²/s²
Significant tornado parameter
0.0
Supercell composite
-0.0
0-3 km lapse rate
9.5 K/km

Open this sounding in Storm Lab

The radar

The Cheyenne radar (KCYS), 208 km away, was scanning. The volume nearest the touchdown began at 21:00 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.

This ground now

The live radar over the trackEvery 2025 tornado in WyomingEvery tornado in Wyoming since 1950Warnings in force in Wyoming nowThe forecast where you are

The other tornadoes of June 17, 2025

21 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
June 1711:41 AM CDTEF0Escambia, FL0.15
June 1712:25 PM MDTEF1Albany, WY1.6450
June 1712:41 PM MDTEF1Teller, CO0.4150
June 171:38 PM MDTUnratedAdams, ND0.950
June 172:15 PM MDTEF0Kimball, NE0.110
June 172:35 PM MDTUnratedNiobrara, WY0.110
June 172:50 PM MDTUnratedNiobrara, WY0.110
June 174:25 PM CDTEF0Harper, KS0.110
June 176:09 PM EDTEF1Bedford, PA1.1175$60,000
June 175:40 PM MDTUnratedMorrill, NE0.110
June 178:06 PM CDTEF2Ellis, OK14.31,200$105,000
June 178:07 PM CDTEF1Ellis, OK1.850$20,000
June 178:16 PM CDTUnratedRoger Mills, OK0.130
June 179:39 PM CDTEF0Alfalfa, OK2.240$10,000
June 179:52 PM CDTUnratedMajor, OK2.030
June 179:53 PM CDTUnratedGrant, OK1.030
June 1712:36 AM CDTEF1Mayes, OK4.3350$300,000
June 1712:42 AM CDTEF1Mayes, OK8.2750
June 1712:53 AM CDTEF1Cherokee, OK1.8700$10,000
June 1712:56 AM CDTEF1Cherokee, OK6.9600$50,000
June 1712:59 AM CDTEF1Delaware, OK3.7700$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.