Tornadoes · United States · Colorado · 2021

Unrated tornado, Blanca, Colorado, June 6, 2021

This Unrated tornado ran 0.1 miles across Costilla County on June 6, 2021, touching down at 2:22 PM MDT and reaching 20 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 6, 2021
Touchdown
2:22 PM MDT (20:22 UTC)
Lifted
2:25 PM MDT (20:25 UTC)
On the ground
3 minutes
Path length
0.1 miles (0.1 km)
Path width
20 yards (18 m)
Deaths
0
Injuries
0
County
Costilla County
Touchdown point
37.359, -105.699
Lift-off point
37.359, -105.699
Record number
2106061422-01

What the Weather Service recorded

Thunderstorm development on this day was mainly confined to the I-25 Corridor and westward, with burn scar flash flooding a primary concern on this day. While this was the main concern, an isolated severe storm did occur across the eastern plains, as well as a brief landspout tornado occurring over the San Luis Valley. This tornado was brief, and did not produce any damage.

Brief landspout tornado.

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 19:48 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.

Albuquerq/Krtlnd, NM (KABQ), 12:00Z

8.4 hours before the tornado, 269 km from the path. June 6, 2021.

Skew-T log-pSkew-T log-p diagram, Albuquerq/Krtlnd, NM at 12:00Z on 2021-06-06Temperature 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 -85493, lifted condensation level 2826 meters above ground. Wind barbs in knots down the right edge.LCL10008507005003002001001 km2 km3 km6 km9 km12 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, Albuquerq/Krtlnd, NM at 12:00Z on 2021-06-06The 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 112 square meters per square second, 0 to 6 km bulk shear 26 knots.1939Sfc1 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
-85493 J/kg
Surface CAPE
10 J/kg
Mixed-layer LCL
2826 m above ground
0-6 km bulk shear
26 kt
0-1 km bulk shear
22 kt
0-1 km storm-relative helicity
112 m²/s²
0-3 km storm-relative helicity
137 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0
0-3 km lapse rate
5.9 K/km

Open this sounding in Storm Lab

Albuquerq/Krtlnd, NM (KABQ), 00:00Z

3.6 hours after it, 269 km from the path. June 7, 2021.

Skew-T log-pSkew-T log-p diagram, Albuquerq/Krtlnd, NM at 00:00Z on 2021-06-07Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 126 joules per kilogram, CIN -4, lifted condensation level 4136 meters above ground. Wind barbs in knots down the right edge.LCLEL10008507005003002001001 km2 km3 km6 km9 km12 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, Albuquerq/Krtlnd, NM at 00:00Z on 2021-06-07The 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 9 square meters per square second, 0 to 6 km bulk shear 14 knots.1939Sfc1 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
126 J/kg
Mixed-layer CIN
-4 J/kg
Surface CAPE
227 J/kg
Mixed-layer LCL
4136 m above ground
0-6 km bulk shear
14 kt
0-1 km bulk shear
6 kt
0-1 km storm-relative helicity
9 m²/s²
0-3 km storm-relative helicity
19 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 surface observations

Alamosa Municipal(Awos) (ALS), 17 km from the path, in the two hours either side.

Time (UTC)Temp (°F)Dew point (°F)WindGust (kt)Pressure (mb)Weather
18:25 UTC290° 7 kt1017.6
18:30 UTC320° 5 kt1017.6
18:40 UTC 1017.6
18:45 UTC330° 4 kt1017.3
18:50 UTC10° 5 kt1017.3
18:52 UTC8139340° 7 kt1017.3
18:55 UTC320° 11 kt1017.3
19:00 UTC10° 5 kt1017.3
19:10 UTC320° 7 kt1017.3
19:15 UTC350° 5 kt1017.3
19:20 UTC290° 11 kt161017.3
19:25 UTC 10 kt1016.9
19:30 UTC340° 7 kt1016.9
19:35 UTC310° 14 kt1016.9
19:40 UTC 1016.9
19:50 UTC270° 19 kt241016.9
19:52 UTC8137260° 21 kt281016.9VCTS
19:55 UTC 19 kt1016.9
20:00 UTC 22 kt271016.9
20:05 UTC 20 kt241016.9
20:10 UTC280° 16 kt1016.9
20:14 UTC7937280° 17 kt261016.9TS
20:15 UTC270° 16 kt1016.9
20:20 UTC340° 11 kt1017.3
20:25 UTC10° 5 kt1016.9-RA
20:26 UTC744120° 6 kt211016.9-RA
20:30 UTC50° 5 kt1016.9-RA
20:35 UTC170° 4 kt1016.9RA
20:38 UTC6851230° 5 kt1016.9VCTS RA
20:40 UTC240° 9 kt1016.9-RA
20:45 UTC250° 15 kt1016.9-RA
20:52 UTC7244240° 14 kt201016.9
20:55 UTC240° 11 kt181016.9
21:00 UTC240° 11 kt1017.3
21:01 UTC7245240° 12 kt1017.6
21:05 UTC240° 13 kt181018.3
21:10 UTC 10 kt1018.6
21:20 UTC150° 4 kt1019
21:25 UTC140° 13 kt1019
21:28 UTC7042130° 12 kt191018.6VCTS
21:30 UTC100° 17 kt241018.6
21:40 UTC130° 10 kt1019-RA
21:45 UTC170° 10 kt1019
21:50 UTC 1019.3
21:52 UTC6940 1019.3
21:55 UTC110° 11 kt1019.6
22:00 UTC110° 9 kt141019.6
22:05 UTC100° 10 kt1019.6
22:10 UTC110° 7 kt1019.6
22:15 UTC100° 13 kt1019.6
22:20 UTC110° 14 kt1019.6

From the Iowa Environmental Mesonet's archive of airport observations.

The radar

The Pueblo radar (KPUX), 181 km away, was scanning. The volume nearest the touchdown began at 20:24 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
20:22 UTCTORNADO11 Wsw BlancaCostilla, COBRIEF LANDSPOUT TORNADO REPORTED VIA SOCIAL MEDIA.

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 6, 2021

1 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
June 69:06 AM CDTEF0Ascension Parish, LA1.125

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.