Tornadoes · United States · Colorado · 2010

EF1 tornado, Lodi to Brush, Colorado, August 16, 2010

From Lodi to Brush, this EF1 tornado ran 0.3 miles across Morgan County on August 16, 2010, touching down at 4:17 PM MDT and reaching 100 yards wide. It killed nobody, and did $50,000 of property damage.

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 mphthis tornado

    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
EF1
Date
August 16, 2010
Touchdown
4:17 PM MDT (22:17 UTC)
Path length
0.3 miles (0.4 km)
Path width
100 yards (91 m)
Deaths
0
Injuries
0
Property damage
$50,000
County
Morgan County
Touchdown point
40.161, -103.564
Lift-off point
40.161, -103.564
Record number
1008161617-01

What the Weather Service recorded

Severe thunderstorms produced nickel size hail and strong winds across parts of Arapahoe, Elbert, Morgan and Weld Counties. Lightning struck a teenager in Littleton and sparked a grass fire in Golden. Four tornadoes reportedly touched down in Arapahoe, Elbert and Morgan Counties. One of the tornadoes destroyed a small barn and damaged a home near Brush.

A tornado touched down briefly but did no damage.

A tornado touched down near a home. It uprooted trees and did some damage to the home, breaking windows some windows. Two horse trailers were picked up and thrown approximately 100 yards. Several hundred yards of fence were torn out of the ground, and several wood and steel fence posts were torn out of the ground. Debris was found up to a mile from where the tornado touched down. A small horse barn that had been recently built was also destroyed; one horse was badly injured and was later euthanized.

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

The warnings

20 minutes of warning. NWS BOU issued a tornado warning for this county at 21:57 UTC, 20 minutes before the tornado touched down, in force until 22:30 UTC.

The county was under a severe thunderstorm watch, issued at 20:38 UTC and running to 03:23 UTC.

Issued (UTC)ExpiredProductOffice
20:38 UTC03:23 UTCSevere Thunderstorm WatchBOU
21:35 UTC21:47 UTCSevere Thunderstorm WarningBOU
21:57 UTC22:30 UTCTornado WarningBOU
22:25 UTC22:54 UTCTornado WarningBOU

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 19:44 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

10.3 hours before the tornado, 43 km from the path. August 16, 2010.

Skew-T log-pSkew-T log-p diagram, Denver, CO at 12:00Z on 2010-08-16Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 874 joules per kilogram, CIN -179, lifted condensation level 828 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, Denver, CO at 12:00Z on 2010-08-16The 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 35 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
874 J/kg
Mixed-layer CIN
-179 J/kg
Surface CAPE
693 J/kg
Mixed-layer LCL
828 m above ground
0-6 km bulk shear
35 kt
0-1 km bulk shear
16 kt
0-1 km storm-relative helicity
78 m²/s²
0-3 km storm-relative helicity
75 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.7
0-3 km lapse rate
4.6 K/km

Open this sounding in Storm Lab

Denver, CO (KDNR), 00:00Z

1.7 hours after it, 43 km from the path. August 17, 2010.

Skew-T log-pSkew-T log-p diagram, Denver, CO at 00:00Z on 2010-08-17Temperature 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 -155, lifted condensation level 2429 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, Denver, CO at 00:00Z on 2010-08-17The 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 -9 square meters per square second, 0 to 6 km bulk shear 43 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
1 J/kg
Mixed-layer CIN
-155 J/kg
Surface CAPE
59 J/kg
Mixed-layer LCL
2429 m above ground
0-6 km bulk shear
43 kt
0-1 km bulk shear
2 kt
0-1 km storm-relative helicity
-9 m²/s²
0-3 km storm-relative helicity
7 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0
0-3 km lapse rate
8.7 K/km

Open this sounding in Storm Lab

The surface observations

Akron/Washington Co (AKO), 29 km from the path, in the two hours either side.

Time (UTC)Temp (°F)Dew point (°F)WindGust (kt)Pressure (mb)Weather
20:53 UTC8360170° 20 kt261018.6
21:53 UTC7960170° 18 kt261017.9
22:51 UTC73.462.6230° 18 kt231017.3-RA
22:52 UTC7363230° 16 kt231017.3-RA
23:21 UTC73.460.8220° 12 kt1017.3-RA
23:53 UTC6561350° 18 kt231018.6-RA
23:59 UTC62.660.8360° 9 kt221019+RA BR

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

The radar

The Denver radar (KFTG), 93 km away, was scanning. The volume nearest the touchdown began at 22:17 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
21:54 UTCTORNADO1 Nnw GaryMorgan, CO
22:17 UTCTORNADO4 N GaryMorgan, CO

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

This ground now

The live radar over the trackEvery 2010 tornado in ColoradoEvery tornado in Colorado since 1950Warnings in force in Colorado nowThe forecast where you are

The other tornadoes of August 16, 2010

3 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
August 161:57 PM MDTEF0Arapahoe, CO0.150
August 162:16 PM MDTEF0Elbert, CO0.150
August 163:54 PM MDTEF0Morgan, CO0.150

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.