Tornadoes · United States · Colorado · 2018
EF1 tornado, Elizabeth, Colorado, July 27, 2018
This EF1 tornado ran 1.2 miles across Elbert County on July 27, 2018, touching down at 3:51 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.
EF065 to 85 mph
Light damage. Surface peeled off some roofs, gutters and siding damaged, branches broken, shallow-rooted trees pushed over.
EF186 to 110 mphthis tornado
Moderate damage. Roofs badly stripped, mobile homes overturned or badly damaged, exterior doors lost, windows broken.
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.
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.
EF4166 to 200 mph
Devastating damage. Well-built houses leveled, structures with weak foundations moved some distance, cars thrown and large missiles generated.
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.
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
- EF1
- Date
- July 27, 2018
- Touchdown
- 3:51 PM MDT (21:51 UTC)
- Lifted
- 3:53 PM MDT (21:53 UTC)
- On the ground
- 2 minutes
- Path length
- 1.2 miles (1.9 km)
- Path width
- 50 yards (46 m)
- Deaths
- 0
- Injuries
- 0
- County
- Elbert County
- Touchdown point
- 39.407, -104.580
- Lift-off point
- 39.390, -104.580
- Record number
- 1807271551-01
The damage survey
2 damage points were recorded along this path by NWS BOU, in the Damage Assessment Toolkit the survey teams carry. The strongest indicator was rated EF1. The highest wind the damage implies is 90 mph.
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
Five tornadoes touched down, three of those produced damage on an EF-1 scale. South of Byers, a tornado took to roof off a manufactured home and partially destroyed an outbuilding. The tornado flipped a UPS truck end over end and injured the driver. The second tornado near Ponderosa Park uprooted several trees. The third tornado near Deer Trail tossed a cattle feeder approximately one-quarter of a mile, blew over some farm equipment and blew out the windows of a home. In addition to the tornadoes, severe thunderstorms produced hail up to golf ball size, heavy rain along with some minor |flooding. Multiple power lines were downed and Eads experienced a power outage.
A tornado touched down briefly and uprooted several trees.
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 tornado watch, issued at 19:05 UTC and running to 01:18 UTC.
| Issued (UTC) | Expired | Product | Office |
|---|---|---|---|
| 04:38 UTC | 05:30 UTC | Severe Thunderstorm Warning | BOU |
| 19:05 UTC | 01:18 UTC | Tornado Watch | BOU |
| 21:08 UTC | 21:45 UTC | Severe Thunderstorm Warning | BOU |
| 21:47 UTC | 22:30 UTC | Severe Thunderstorm Warning | BOU |
| 22:08 UTC | 22:49 UTC | Severe Thunderstorm Warning | BOU |
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 19:58 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 (KDEN), 12:00Z
9.9 hours before the tornado, 127 km from the path. July 27, 2018.
- Mixed-layer CAPE
- 735 J/kg
- Mixed-layer CIN
- -87 J/kg
- Surface CAPE
- 460 J/kg
- Mixed-layer LCL
- 574 m above ground
- 0-6 km bulk shear
- 27 kt
- 0-1 km bulk shear
- 16 kt
- 0-1 km storm-relative helicity
- 13 m²/s²
- 0-3 km storm-relative helicity
- 91 m²/s²
- Significant tornado parameter
- 0.1
- Supercell composite
- 1.1
- 0-3 km lapse rate
- 4.6 K/km
Denver, CO (KDEN), 00:00Z
2.1 hours after it, 127 km from the path. July 28, 2018.
- Mixed-layer CAPE
- 683 J/kg
- Mixed-layer CIN
- -79 J/kg
- Surface CAPE
- 1906 J/kg
- Mixed-layer LCL
- 1183 m above ground
- 0-6 km bulk shear
- 28 kt
- 0-1 km bulk shear
- 5 kt
- 0-1 km storm-relative helicity
- -4 m²/s²
- 0-3 km storm-relative helicity
- 194 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.3
- 0-3 km lapse rate
- 6.8 K/km
The radar
The Denver radar (KFTG), 43 km away, was scanning. The volume nearest the touchdown began at 21:49 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) | Report | Where | County | Remark |
|---|---|---|---|---|
| 21:12 UTC | HAIL 1.25 | 7 Ne Ponderosa Park | Elbert, CO | |
| 21:56 UTC | TORNADO | 7 S Byers | Arapahoe, CO | *** 1 INJ *** ROOF TORN OFF HOUSE. FLIPPED UPS TRUCK. 1 INJURY. TIME ESTIMATED. |
| 22:00 UTC | TORNADO | 2 Ne Ponderosa Park | Elbert, CO | TRAINED SPOTTER REPORTED A BRIEF AND WEAK TORNADO. |
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 July 27, 2018
6 more were confirmed in the United States that day.
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.