Tornadoes · United States · Colorado · 2023

EF0 tornado, Washington County, Colorado, August 8, 2023

This EF0 tornado ran 0.0 miles across Washington County on August 8, 2023, touching down at 5:29 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
August 8, 2023
Touchdown
5:29 PM MDT (23:29 UTC)
Lifted
5:31 PM MDT (23:31 UTC)
On the ground
2 minutes
Path length
0.0 miles (0.0 km)
Path width
50 yards (46 m)
Deaths
0
Injuries
0
County
Washington County
Touchdown point
40.176, -102.929
Lift-off point
40.176, -102.929
Record number
2308081729-01

The damage survey

32 damage points were recorded along this path by NWS BOU and NWS GLD, in the Damage Assessment Toolkit the survey teams carry. The strongest indicator was rated EF3. The highest wind the damage implies is 150 mph.

  • Garage was lifted off foundation with imploded garage doors. Southwest corner of the garage lost about 10% of the roof structure. Garage is east facing and was pulled to the east off the anchoring and then to the north slightly.
  • Large living softwood tree snapped near the base of the trunk. Trunk was slightly rotted.
  • Metal shack had tin roof spaniels ripped off along with 3 2x4 beams. Material was tossed NW (320 degrees) to the tree line. One piece of tin went to the east.
  • Tin storage container was flipped to the south.

Survey points are preliminary and are the raw material the published rating was built from. Source: NWS Damage Assessment Toolkit.

The warnings

No tornado warning for this county appears in the archive as in force at the moment the tornado touched down. One was issued for the county at another hour that day.

The county was under a severe thunderstorm watch, issued at 20:38 UTC and running to 04:00 UTC.

Issued (UTC)ExpiredProductOffice
20:38 UTC04:00 UTCSevere Thunderstorm WatchBOU
21:53 UTC22:45 UTCSevere Thunderstorm WarningBOU
22:17 UTC00:48 UTCFlood AdvisoryBOU
22:31 UTC23:00 UTCTornado WarningBOU
23:36 UTC00:03 UTCSevere Thunderstorm WarningBOU
23:54 UTC00:20 UTCSevere Thunderstorm WarningBOU
23:55 UTC00:19 UTCSevere Thunderstorm WarningBOU
00:06 UTC00:30 UTCSevere Thunderstorm WarningBOU
00:13 UTC00:44 UTCSevere Thunderstorm WarningBOU
04:50 UTC05:15 UTCSevere Thunderstorm 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 Enhanced Risk, with a 0.05 chance of a tornado within 25 miles. The outlook in force was issued at 19:57 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.

N. Platte/Lee Bi, NE (KLBF), 12:00Z

11.5 hours before the tornado, 223 km from the path. August 8, 2023.

Skew-T log-pSkew-T log-p diagram, N. Platte/Lee Bi, NE at 12:00Z on 2023-08-08Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 4 joules per kilogram, CIN -289, lifted condensation level 695 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, N. Platte/Lee Bi, NE at 12:00Z on 2023-08-08The 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 61 square meters per square second, 0 to 6 km bulk shear 45 knots.19395878Sfc1 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
4 J/kg
Mixed-layer CIN
-289 J/kg
Surface CAPE
0 J/kg
Mixed-layer LCL
695 m above ground
0-6 km bulk shear
45 kt
0-1 km bulk shear
13 kt
0-1 km storm-relative helicity
61 m²/s²
0-3 km storm-relative helicity
205 m²/s²
Significant tornado parameter
0.0
Supercell composite
-0.1
0-3 km lapse rate
4.0 K/km

Open this sounding in Storm Lab

N. Platte/Lee Bi, NE (KLBF), 00:00Z

0.5 hours after it, 223 km from the path. August 9, 2023.

Skew-T log-pSkew-T log-p diagram, N. Platte/Lee Bi, NE at 00:00Z on 2023-08-09Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 1804 joules per kilogram, CIN -29, lifted condensation level 1179 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, N. Platte/Lee Bi, NE at 00:00Z on 2023-08-09The 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 38 square meters per square second, 0 to 6 km bulk shear 31 knots.19395878Sfc1 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
1804 J/kg
Mixed-layer CIN
-29 J/kg
Surface CAPE
2866 J/kg
Mixed-layer LCL
1179 m above ground
0-6 km bulk shear
31 kt
0-1 km bulk shear
7 kt
0-1 km storm-relative helicity
38 m²/s²
0-3 km storm-relative helicity
106 m²/s²
Significant tornado parameter
0.5
Supercell composite
4.6
0-3 km lapse rate
7.1 K/km

Open this sounding in Storm Lab

The radar

The Goodland radar (KGLD), 138 km away, was scanning. The volume nearest the touchdown began at 23:30 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
22:08 UTCHAIL 1.756 S BurdettWashington, CO
22:50 UTCTORNADO2 Nw HydeWashington, COCorrects time based on radar. Report from 2 NW Hyde. WA298, seen from Yuma.
22:55 UTCTSTM WND DMG1 W HydeWashington, COSmall barn flipped on its side. Estimated wind gust to 90 mph per damage indicator. Also minor shingle damage to manufactured home at this location. Time estimated by other real time reports and radar data.
22:57 UTCTORNADO1 Ese HydeWashington, COGarage was lifted off foundation anchoring and shifted. Garage doors imploded, and about 10% of roof structure was lost. Other tree damage on farm suggested EF1 damage as well, including snapped trees and broken wood pow
22:57 UTCTORNADO2 Nw HydeWashington, COWA298, seen from Yuma.
23:00 UTCTSTM WND DMG1 Wnw HydeWashington, COPub State patrol.
23:00 UTCHAIL 1.754 Ne YumaYuma, CODelayed report via social media.
23:00 UTCHAIL 2.757 N AbarrYuma, CODelayed report via social media with picture. Time estimated.
23:02 UTCHAIL 3HydeWashington, CODE175.
23:02 UTCTORNADO2 Sw YumaYuma, COTornado on the ground estimated 3 miles west of the airport. Location estimated.
23:05 UTCHAIL 2.251 Wnw HydeWashington, COReport from mPING: Hen Egg+ (2.25 in.).
23:07 UTCHAIL 3HydeWashington, COReport from mPING: Tea Cup (3.00 in.).
23:08 UTCHAIL 43 W YumaYuma, CO
23:13 UTCTORNADO5 S YumaYuma, CO5 power poles snapped along Hwy 59. Time estimated.
23:15 UTCHAIL 2.757 N AbarrYuma, COCorrects previous hail report from 7 N Abarr. Delayed report via social media with picture. Time estimated.
23:16 UTCHAIL 14 Se YumaYuma, COReport from mPING: Quarter (1.00 in.).
23:18 UTCHAIL 1.754 Ese YumaYuma, COHail was ongoing at the location.
23:20 UTCTSTM WND DMG3 S YumaYuma, CODelayed report. Top branches of a tree snapped off and laying towards the southeast. Time estimated via radar.
23:20 UTCTSTM WND DMG3 S YumaYuma, COCorrects previous tornado report from 5 S Yuma from a NWS Storm Survey. 5 power poles snapped along Hwy 59. Time estimated.
23:30 UTCTORNADO7 Nnw HeartstrongYuma, CODelayed report via social media. Multi-vortex tornado reported roughly 7-8 miles southeast of Yuma. Location approximate based on radar. Tornado has lifted prior to 5:51 PM MDT.
23:34 UTCHAIL 36 Nnw HeartstrongYuma, CODelayed report via social media with photo of hailstones. Time estimated.
23:40 UTCTORNADO6 Nw HeartstrongYuma, COCorrects previous DELAYED REPORT tornado report from 6 NW Heartstrong. DELAYED REPORT of a tornado 1.5-2 Miles west of CR 30 and K. Videos and photos sent in via social media.
23:40 UTCTORNADO6 Nw HeartstrongYuma, CODELAYED REPORT of a tornado 1.5-2 Miles west of CR 30 and K. Time is estimated by reporter and radar.
23:45 UTCHAIL 1.757 Sse HydeWashington, COLost power as well.
23:45 UTCHAIL 1.756 Ssw YumaYuma, COUp to golf ball hail observed. Power was out at the residence.
23:59 UTCHAIL 1.257 S YumaYuma, COReport from mPING: Half Dollar (1.25 in.).
00:06 UTCTORNADO2 Nne AbarrYuma, COBrief tornado lasted about 2 minutes (6:08PM) roughly 2-3 miles NW of County Rds L and and 18 intersection.
00:17 UTCHAIL 1.57 N AbarrYuma, COReport from mPING: Ping Pong Ball (1.50 in.).
00:19 UTCTSTM WND GST 601 Ese AbarrYuma, CO
00:19 UTCTORNADO5 Sw HeartstrongYuma, COTornado just touched down via Chaser live feed. Location estimated via radar.
00:20 UTCHAIL 2.56 N AbarrYuma, COReport from mPING: Tennis Ball (2.50 in.).
00:25 UTCTORNADO3 E AbarrYuma, COStorm chasers were 7 miles north of Joes looking to the northwest. They commented they saw rope tornado for about a minute and a half, emerging out of rain shaft. Position estimated by radar.
00:30 UTCHAIL 46 Wsw HeartstrongYuma, COStorm chaser reported 3.5 inch to 4 inch hail near the intersection of Highway 59 and County Road 25 at approximately 6:30 pm MDT.
00:30 UTCTORNADO5 Se AbarrYuma, COOngoing tornado reported. Location roughly 10 miles NW of Kirk. Location estimated via radar and report.

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

This ground now

The live radar over the trackEvery 2023 tornado in ColoradoEvery tornado in Colorado since 1950Warnings in force in Colorado nowThe forecast where you are

The other tornadoes of August 8, 2023

13 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
August 811:20 AM EDTEF1Plymouth, MA0.9300$10,000
August 811:52 AM EDTEF0Barnstable, MA1.2650$2,000
August 812:50 PM MSTEF0Coconino, AZ5.010
August 84:29 PM MDTUnratedWashington, CO0.050
August 84:39 PM MDTEF3Washington, CO15.7212$1.0 million
August 84:50 PM MDTUnratedMorrill, NE0.125
August 85:30 PM MDTUnratedYuma, CO5.3200
August 86:04 PM MDTEF0Yuma, CO1.7193
August 86:19 PM MDTUnratedYuma, CO1.0150
August 86:23 PM MDTUnratedYuma, CO0.975
August 87:00 PM MDTUnratedYuma, CO0.5150
August 87:25 PM MDTEF2Kit Carson, CO5.3150$30,000
August 89:17 PM MDTUnratedSherman, KS1.375

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.