Tornadoes · United States · Colorado · 2015

EF0 tornado, Vilas, Colorado, May 28, 2015

This EF0 tornado ran 0.4 miles across Baca County on May 28, 2015, touching down at 3:53 PM 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
May 28, 2015
Touchdown
3:53 PM MDT (21:53 UTC)
Lifted
3:56 PM MDT (21:56 UTC)
On the ground
3 minutes
Path length
0.4 miles (0.7 km)
Path width
50 yards (46 m)
Deaths
0
Injuries
0
County
Baca County
Touchdown point
37.227, -102.375
Lift-off point
37.233, -102.378
Record number
1505281553-01

What the Weather Service recorded

Severe storms produced quarter size hail and two tornadoes in Las Animas and Baca Counties.

A landspout moved across open country, narrowly missing a ranch, and caused no damage.

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

The warnings

45 minutes of warning. NWS PUB issued a tornado warning for this county at 21:08 UTC, 45 minutes before the tornado touched down, in force until 22:00 UTC.

The county was under a severe thunderstorm watch, issued at 19:21 UTC and running to 01:17 UTC.

Issued (UTC)ExpiredProductOffice
19:21 UTC01:17 UTCSevere Thunderstorm WatchPUB
21:08 UTC22:00 UTCTornado WarningPUB
21:13 UTC22:00 UTCSevere Thunderstorm WarningPUB
21:50 UTC22:32 UTCSevere Thunderstorm WarningPUB
21:56 UTC22:30 UTCTornado WarningPUB
22:23 UTC22:32 UTCTornado WarningPUB
22:50 UTC23:11 UTCSevere Thunderstorm WarningPUB

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 Slight Risk, with a 0.02 chance of a tornado within 25 miles. The outlook in force was issued at 19:32 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.

Dodge City, (KDDC), 12:00Z

9.9 hours before the tornado, 227 km from the path. May 28, 2015.

Skew-T log-pSkew-T log-p diagram, Dodge City, at 12:00Z on 2015-05-28Temperature 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 -92072, lifted condensation level 2337 meters above ground. Wind barbs in knots down the right edge.LCL10008507005003002001001 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, Dodge City, at 12:00Z on 2015-05-28The 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 -67 square meters per square second, 0 to 6 km bulk shear 34 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
-92072 J/kg
Surface CAPE
0 J/kg
Mixed-layer LCL
2337 m above ground
0-6 km bulk shear
34 kt
0-1 km bulk shear
13 kt
0-1 km storm-relative helicity
-67 m²/s²
0-3 km storm-relative helicity
14 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0
0-3 km lapse rate
4.9 K/km

Open this sounding in Storm Lab

Dodge City, (KDDC), 00:00Z

2.1 hours after it, 227 km from the path. May 29, 2015.

Skew-T log-pSkew-T log-p diagram, Dodge City, at 00:00Z on 2015-05-29Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 1000 joules per kilogram, CIN -32, lifted condensation level 1378 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, Dodge City, at 00:00Z on 2015-05-29The 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 78 square meters per square second, 0 to 6 km bulk shear 33 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
1000 J/kg
Mixed-layer CIN
-32 J/kg
Surface CAPE
2294 J/kg
Mixed-layer LCL
1378 m above ground
0-6 km bulk shear
33 kt
0-1 km bulk shear
16 kt
0-1 km storm-relative helicity
78 m²/s²
0-3 km storm-relative helicity
146 m²/s²
Significant tornado parameter
0.3
Supercell composite
4.9
0-3 km lapse rate
7.3 K/km

Open this sounding in Storm Lab

The surface observations

Springfield/Comanche Natl Grass (SPD), 22 km from the path, in the two hours either side.

Time (UTC)Temp (°F)Dew point (°F)WindGust (kt)Pressure (mb)Weather
19:56 UTC6957240° 8 kt1015.6
20:56 UTC6859250° 3 kt1014.9
21:56 UTC6949270° 12 kt161012.2
22:44 UTC6149170° 18 kt321013.9
22:56 UTC6247110° 19 kt1011.5
23:03 UTC5851110° 20 kt251011.5

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

The radar

The Pueblo radar (KPUX), 209 km away, was scanning. The volume nearest the touchdown began at 21:51 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
21:15 UTCHAIL 0.887 Se StoningtonBaca, CO
21:55 UTCTORNADO15 S VilasBaca, CO

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

This ground now

The live radar over the trackEvery 2015 tornado in ColoradoEvery tornado in Colorado since 1950Warnings in force in Colorado nowThe forecast where you are

The other tornadoes of May 28, 2015

13 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
May 289:58 AM CDTEF1LeFlore, OK0.575$50,000
May 282:09 PM CDTEF1Benton, AR1.6100$25,000
May 282:40 PM CDTEF0Benton, AR0.250$10,000
May 282:14 PM MDTEF0Greeley, KS0.520
May 283:37 PM CDTEF0Borden, TX1.150
May 282:38 PM MDTEF0Las Animas, CO0.350
May 283:53 PM CDTEF0Wichita, KS1.950
May 284:07 PM CDTEF0Wichita, KS0.325
May 283:35 PM MDTEF0Kit Carson, CO1.025
May 284:50 PM CDTEF0Scott, KS1.975
May 285:09 PM CDTEF0Finney, KS1.775
May 285:17 PM CDTEF0Walsh, ND2.0100
May 288:13 PM CDTEF0Foard, TX0.550

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.