Tornadoes · United States · Colorado · 2023

Unrated tornado, Black Forest, Colorado, August 5, 2023

This Unrated tornado ran 2.2 miles across El Paso County on August 5, 2023, touching down at 1:40 PM MDT and reaching 10 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 mph

    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. Unratedthis tornado

    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
Unrated
Date
August 5, 2023
Touchdown
1:40 PM MDT (19:40 UTC)
Lifted
1:44 PM MDT (19:44 UTC)
On the ground
4 minutes
Path length
2.2 miles (3.5 km)
Path width
10 yards (9 m)
Deaths
0
Injuries
0
County
El Paso County
Touchdown point
39.070, -104.670
Lift-off point
39.056, -104.634
Record number
2308051340-01

What the Weather Service recorded

The one and only time this year when there was a proper monsoonal tap over southern Colorado. In this case, there was weak northweserly flow aloft, and southeasterly flow at the surface, which resulted in a unstable and high shear environment. There was almost a tornado that touched down, however, no reports of debris or damage were reported.

Trained spotter saw the tornado on the ground around 3 to 4 miles north of his location.

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. One was issued for the county at another hour that day.

The county was under a severe thunderstorm watch, issued at 19:34 UTC and running to 03:40 UTC.

Issued (UTC)ExpiredProductOffice
19:29 UTC20:15 UTCSevere Thunderstorm WarningPUB
19:34 UTC03:40 UTCSevere Thunderstorm WatchPUB
19:43 UTC20:30 UTCTornado WarningPUB
19:49 UTC20:15 UTCTornado WarningPUB
19:53 UTC20:45 UTCSevere Thunderstorm WarningPUB
20:04 UTC20:30 UTCTornado WarningPUB
20:18 UTC21:00 UTCSevere Thunderstorm WarningPUB
20:27 UTC21:15 UTCSevere Thunderstorm WarningPUB
20:30 UTC21:00 UTCSevere Thunderstorm WarningPUB
20:36 UTC21:00 UTCTornado WarningPUB
20:59 UTC21:30 UTCSevere Thunderstorm WarningPUB
21:08 UTC21:45 UTCTornado WarningPUB
21:14 UTC21:45 UTCTornado WarningPUB
21:14 UTC22:00 UTCSevere Thunderstorm WarningPUB
21:14 UTC22:00 UTCSevere Thunderstorm WarningPUB
21:27 UTC22:15 UTCTornado WarningPUB
21:44 UTC22:30 UTCSevere Thunderstorm WarningPUB
21:49 UTC22:15 UTCTornado WarningPUB
21:59 UTC22:15 UTCTornado WarningPUB
22:09 UTC22:16 UTCTornado 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 Enhanced Risk. The outlook in force was issued at 16:27 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.

Grand Junction, CO (KGJT), 12:00Z

7.7 hours before the tornado, 332 km from the path. August 5, 2023.

Skew-T log-pSkew-T log-p diagram, Grand Junction, CO at 12:00Z on 2023-08-05Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 6 joules per kilogram, CIN -331, lifted condensation level 2640 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, Grand Junction, CO at 12:00Z on 2023-08-05The 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 -47 square meters per square second, 0 to 6 km bulk shear 48 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
6 J/kg
Mixed-layer CIN
-331 J/kg
Surface CAPE
0 J/kg
Mixed-layer LCL
2640 m above ground
0-6 km bulk shear
48 kt
0-1 km bulk shear
11 kt
0-1 km storm-relative helicity
-47 m²/s²
0-3 km storm-relative helicity
79 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0
0-3 km lapse rate
6.2 K/km

Open this sounding in Storm Lab

Grand Junction, CO (KGJT), 00:00Z

4.3 hours after it, 332 km from the path. August 6, 2023.

Skew-T log-pSkew-T log-p diagram, Grand Junction, CO at 00:00Z on 2023-08-06Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 9 joules per kilogram, CIN -19, lifted condensation level 4292 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, Grand Junction, CO at 00:00Z on 2023-08-06The 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 -10 square meters per square second, 0 to 6 km bulk shear 50 knots.1939587897117Sfc1 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
9 J/kg
Mixed-layer CIN
-19 J/kg
Surface CAPE
263 J/kg
Mixed-layer LCL
4292 m above ground
0-6 km bulk shear
50 kt
0-1 km bulk shear
7 kt
0-1 km storm-relative helicity
-10 m²/s²
0-3 km storm-relative helicity
21 m²/s²
Significant tornado parameter
0.0
Supercell composite
-0.1
0-3 km lapse rate
10.1 K/km

Open this sounding in Storm Lab

The radar

The Pueblo radar (KPUX), 79 km away, was scanning. The volume nearest the touchdown began at 19:41 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
19:30 UTCHAIL 15 N PeytonEl Paso, CO
19:37 UTCHAIL 1.752 Wnw FondisElbert, COReport via social media, with photos of roughly ping pong to golf ball size hail. Time estimated by radar.
19:40 UTCTORNADO4 Nne Black ForestEl Paso, COSpotter can visually see tornado on the ground about 3 to 4 miles north of their location.
19:43 UTCHAIL 22 Ene FondisElbert, COSocial media report of up to 2 inch diameter hail on County Road 102 east of Elbert. Time and location estimated by radar.
20:00 UTCHAIL 113 Nnw SimlaElbert, CO
20:03 UTCFUNNEL CLOUD4 Nne Black ForestEl Paso, COCorrects previous tornado report from 4 NNE Black Forest. Spotter can visually see a funnel cloud to the west beginning to appear, just north of Monument.
20:03 UTCTORNADO4 Nne Black ForestEl Paso, COSpotter can visually see a funnel cloud to the west beginning to appear, just north of Monument.
20:10 UTCFUNNEL CLOUD5 Sse Air Force AcademyEl Paso, COCorrects previous tornado report from 5 SSE Air Force Academy. Spotter can visually see a funnel cloud to the northeast of location, just east of Monument, near Black Forest.
20:10 UTCTORNADO5 Sse Air Force AcademyEl Paso, COSpotter can visually see a funnel cloud to the northeast of location, just east of Monument, near Black Forest.
20:13 UTCHAIL 1.252 Nw Air Force AcademyEl Paso, COReport from mPING: Half Dollar (1.25 in.).
20:15 UTCHAIL 12 Sse Air Force AcademyEl Paso, CO
20:15 UTCTORNADO4 Ene Air Force AcademyEl Paso, COSpotter reported visually seeing a funnel cloud within the past 5 minutes towards the northeast near Black Forest.
20:20 UTCHAIL 12 Se Air Force AcademyEl Paso, COLocated on I-25, just north of Air Force Academy.
20:22 UTCHAIL 11 Nnw Air Force AcademyEl Paso, COReport from mPING: Quarter (1.00 in.).
20:22 UTCHAIL 13 Ese Air Force AcademyEl Paso, CO
20:27 UTCHAIL 1.255 Ese Air Force AcademyEl Paso, COReport from mPING: Half Dollar (1.25 in.).
20:30 UTCFUNNEL CLOUD6 Nne FalconEl Paso, COSpotter can visually see an active wall cloud with a brief funnel cloud sited within past 5 minutes.
20:35 UTCHAIL 1.755 Sw Black ForestEl Paso, COPictures relayed via broadcast media.
20:38 UTCHAIL 1.253 E Air Force AcademyEl Paso, CO
20:40 UTCHAIL 1.755 Ssw Black ForestEl Paso, CO
20:45 UTCHAIL 1.53 W FalconEl Paso, CONumerous reports of hail 1.00 to 1.5 inches in this immediate region.
20:46 UTCHAIL 1.52 Ssw FalconEl Paso, CO
20:46 UTCHAIL 1.751 E Peterson AfbEl Paso, COReport from mPING: Golf Ball (1.75 in.).
20:49 UTCHAIL 1.754 Wsw FalconEl Paso, CO
20:53 UTCHAIL 23 Ne Peterson AfbEl Paso, CONumerous reports of ping pong to golf ball size hail.
20:56 UTCHAIL 1.54 Ne Peterson AfbEl Paso, COReport from mPING: Ping Pong Ball (1.50 in.).
20:57 UTCHAIL 23 Ne Peterson AfbEl Paso, CO
20:57 UTCHAIL 24 Ne Peterson AfbEl Paso, CO
20:59 UTCHAIL 1.755 N Peterson AfbEl Paso, COReport from mPING: Golf Ball (1.75 in.).
21:00 UTCHAIL 1.52 W Schriever AfbEl Paso, COReport from mPING: Ping Pong Ball (1.50 in.).
21:00 UTCHAIL 1.54 Nnw Peterson AfbEl Paso, COReport from mPING: Ping Pong Ball (1.50 in.).
21:00 UTCHAIL 1.753 N Peterson AfbEl Paso, CO
21:08 UTCHAIL 2.52 Sw Schriever AfbEl Paso, COReport from mPING: Tennis Ball (2.50 in.).
21:14 UTCHAIL 2.754 Ssw Schriever AfbEl Paso, COReport from mPING: Baseball (2.75 in.).
21:23 UTCHAIL 12 Ese SecurityEl Paso, CO
21:23 UTCHAIL 1.255 E SecurityEl Paso, COReport from mPING: Half Dollar (1.25 in.).
21:26 UTCHAIL 2.57 Sse Schriever AfbEl Paso, COReport from mPING: Tennis Ball (2.50 in.).
21:31 UTCHAIL 1.254 E SecurityEl Paso, CO
21:35 UTCHAIL 1.251 Nne SecurityEl Paso, COrelayed via social media.
21:43 UTCHAIL 111 Sse Schriever AfbEl Paso, COReport from mPING: Quarter (1.00 in.).

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 5, 2023

9 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
August 52:24 AM CDTEF1Adams, IL2.9200
August 52:30 PM CDTEF0Sioux, IA0.930
August 52:42 PM CDTUnratedSioux, IA0.110
August 55:15 PM CDTEF0Jackson, IL0.525
August 55:30 PM CDTUnratedJasper, IL0.120
August 57:53 PM CDTUnratedDodge, NE0.125
August 59:24 PM CDTUnratedCarroll, IA0.325
August 59:29 PM CDTEF0Sac, IA0.935$50,000
August 59:30 PM CDTUnratedSac, IA0.350

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.