Tornadoes · United States · Colorado · 2004
F0 tornado, Cheyenne Wells, Colorado, May 12, 2004
This F0 tornado ran 0.5 miles across Cheyenne County on May 12, 2004, touching down at 6:13 PM MDT and reaching 50 yards wide. It killed nobody.
The rating scale
Tracks are drawn in the color of the rating. The Fujita scale rates the damage rather than measuring the wind: the speeds are what that damage is taken to imply.
F040 to 72 mphthis tornado
Light damage. Surface peeled off some roofs, gutters and siding damaged, branches broken, shallow-rooted trees pushed over.
F173 to 112 mph
Moderate damage. Roofs badly stripped, mobile homes overturned or badly damaged, exterior doors lost, windows broken.
F2113 to 157 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.
F3158 to 206 mph
Severe damage. Whole stories of well-built houses destroyed, large buildings badly damaged, trains overturned, trees debarked, heavy cars lifted and thrown.
F4207 to 260 mph
Devastating damage. Well-built houses leveled, structures with weak foundations moved some distance, cars thrown and large missiles generated.
F5261 to 318 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.
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
- F0
- Date
- May 12, 2004
- Touchdown
- 6:13 PM MDT (00:13 UTC)
- Path length
- 0.5 miles (0.8 km)
- Path width
- 50 yards (46 m)
- Deaths
- 0
- Injuries
- 0
- County
- Cheyenne County
- Touchdown point
- 38.770, -102.420
- Lift-off point
- 38.770, -102.420
- Record number
- 1165
What the Weather Service recorded
Thunderstorms developed over several hours across southern Cheyenne County Colorado along a surface boundary and moved into portions of west-central Kansas during the evening. Several reports of tornadoes were received from storm spotters and law enforcement, including one tornado which toppled a windmill and pushed over numerous large trees. Strong thunderstorm winds also accompanied some of the thunderstorms with one downburst, associated with a strong rear-flank downdraft, removing a barn roof. Hail reports between 1 and 3 inches in diameter were common with the storms during the late afternoon and early evening hours.
Brief touchdown over open fields observed by storm chaser. No known damage.
Brief touchdown over open fields observed by law enforcement. No known damage.
From NOAA NCEI's Storm Events Database, the narrative the local forecast office wrote for Storm Data.
The warnings
38 minutes of warning. NWS GLD issued a tornado warning for this county at 23:35 UTC, 38 minutes before the tornado touched down, in force until 00:15 UTC.
| Issued (UTC) | Expired | Product | Office |
|---|---|---|---|
| 23:11 UTC | 00:15 UTC | Severe Thunderstorm Warning | GLD |
| 23:35 UTC | 00:15 UTC | Tornado Warning | GLD |
| 00:16 UTC | 01:15 UTC | Tornado Warning | GLD |
| 00:56 UTC | 02:00 UTC | Severe Thunderstorm Warning | GLD |
| 01:16 UTC | 02:15 UTC | Severe Thunderstorm Warning | GLD |
| 01:45 UTC | 02:15 UTC | Tornado Warning | GLD |
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 23:04 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
11.8 hours after it, 141 km from the path. May 13, 2004.
- Mixed-layer CAPE
- 0 J/kg
- Mixed-layer CIN
- -83805 J/kg
- Surface CAPE
- 0 J/kg
- Mixed-layer LCL
- 556 m above ground
- 0-6 km bulk shear
- 47 kt
- 0-1 km bulk shear
- 4 kt
- 0-1 km storm-relative helicity
- 11 m²/s²
- 0-3 km storm-relative helicity
- 140 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
- 0-3 km lapse rate
- 5.2 K/km
What was reported nearby
Local storm reports within 60 km of the path, in the three hours either side.
| Time (UTC) | Report | Where | County | Remark |
|---|---|---|---|---|
| 23:45 UTC | HAIL 0.75 | 9 Se Kit Carson | Cheyenne, CO | |
| 23:54 UTC | HAIL 0.75 | 9 Se Kit Carson | Cheyenne, CO | HAIL COVERING THE GROUND |
| 00:13 UTC | TORNADO | 5 Sw Cheyenne Wells | Cheyenne, CO | |
| 00:38 UTC | TORNADO | 3 Se Cheyenne Wells | Cheyenne, CO | |
| 00:50 UTC | HAIL 1 | 10 S Arapahoe | Cheyenne, CO | |
| 01:09 UTC | HAIL 1 | 12 S Arapahoe | Cheyenne, CO | |
| 01:09 UTC | HAIL 2.75 | 11 S Arapahoe | Cheyenne, CO | |
| 01:28 UTC | HAIL 0.75 | Wild Horse | Cheyenne, CO | GROUND COVERED 1 INCH DEEP |
| 01:37 UTC | HAIL 1 | 14 Sw Cheyenne Wells | Cheyenne, CO | |
| 01:40 UTC | TORNADO | 10 Se Kit Carson | Cheyenne, CO | WINDMILL DESTROYED AND TREES FLATTENED |
| 02:20 UTC | HAIL 0.75 | Arapahoe | Cheyenne, CO |
From the Iowa Environmental Mesonet's archive of National Weather Service local storm reports.
This ground now
The live radar over the trackEvery 2004 tornado in ColoradoEvery tornado in Colorado since 1950Warnings in force in Colorado nowThe forecast where you are
The other tornadoes of May 12, 2004
17 more were confirmed in the United States that day.
| Date | Time | Rating | Where | Path (mi) | Width (yd) | Deaths | Injuries | Damage |
|---|---|---|---|---|---|---|---|---|
| May 12 | 7:01 PM CDT | F0 | Pratt, KS | 0.5 | 20 | |||
| May 12 | 7:04 PM CDT | F0 | Barber, KS | 0.3 | 40 | |||
| May 12 | 7:08 PM CDT | F1 | Barber, KS | 2.5 | 120 | $10,000 | ||
| May 12 | 7:22 PM CDT | F0 | Jefferson Parish, LA | 0.3 | 25 | $2,000 | ||
| May 12 | 6:38 PM MDT | F0 | Cheyenne, CO | 0.5 | 50 | |||
| May 12 | 7:53 PM CDT | F0 | Harper, KS | 0.3 | 50 | |||
| May 12 | 8:02 PM CDT | F2 | Harper, KS | 1.8 | 200 | $140,000 | ||
| May 12 | 8:14 PM CDT | F1 | Harper, KS | 4.0 | 125 | |||
| May 12 | 8:32 PM CDT | F0 | Harper, KS | 1.0 | 50 | |||
| May 12 | 8:40 PM CDT | F4 | Harper tornado, KS | 1.2 | 500 | 1 | $280,000 | |
| May 12 | 7:40 PM MDT | F1 | Cheyenne, CO | 0.5 | 100 | |||
| May 12 | 9:02 PM CDT | F0 | Harper, KS | 1.2 | 75 | |||
| May 12 | 9:05 PM CDT | F1 | Harper, KS | 1.5 | 75 | $220,000 | ||
| May 12 | 9:10 PM CDT | F2 | Harper, KS | 2.0 | 300 | $140,000 | ||
| May 12 | 9:18 PM CDT | F2 | Harper, KS | 1.0 | 100 | $100,000 | ||
| May 12 | 9:45 PM CDT | F1 | Harper, KS | 3.5 | 100 | $100,000 | ||
| May 12 | 10:05 PM CDT | F1 | Sumner, KS | 2.5 | 150 | $100,000 |
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.