EF1 tornado, Highlands Ranch, Colorado, June 22, 2023

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.

Rating

EF1

Date

June 22, 2023

Touchdown

3:24 PM MDT (21:24 UTC)

Lifted

3:48 PM MDT (21:48 UTC)

On the ground

24 minutes

Path length

6.3 miles (10.1 km)

Path width

25 yards (23 m)

Deaths

0

Injuries

0

County

Douglas County

Touchdown point

39.556, -105.016

Lift-off point

39.535, -104.909

Record number

2306221524-01

A supercell thunderstorm formed in the higher terrain west of Denver and moved across the Arapahoe/Douglas County line, from the west metro Denver to south Metro Denver. Up to 2.5 inches hail occurred in the populated areas of Jefferson County. An EF1 tornado touched down just south of CO-470 in the city of Highlands Ranch. Preliminarily the tornado was on the ground for 6.3 miles. No injuries were reported but over 100 trees were downed. Some window/shingle damage has been noted to both houses and commercial properties. South Metro Fire Dapartment responded to dozens of calls in Highlands Ranch south of c470 between Lucent and Quebec for storm related damage including roof damage, trees down, natural gas leaks and electrical problems. |At Northridge Elementary School a tree had fallen on the school and portions of the roof were been ripped off. Valor Christian High School in Highlands Ranch also sustained damage.

A tornado touched down just south of CO-470 in Douglas County, west of Lucent Blvd, impacting the city of Highlands Ranch. The tornado lifted just west of the intersection of Lincoln Ave and Lone Tree Parkway. Most all of the damage was rated EF-0, with small pockets of EF1 damage as well which involved a well built single family home.

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

2 minutes of warning. NWS BOU issued a tornado warning for this county at 21:22 UTC, 2 minutes before the tornado touched down, in force until 22:00 UTC.

The county was under a severe thunderstorm watch, issued at 18:17 UTC and running to 01:27 UTC.

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 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 20:00 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 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/Centennial (APA), 10 km from the path, in the two hours either side.

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

The Denver radar (KFTG), 45 km away, was scanning. The volume nearest the touchdown began at 21:25 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.

Local storm reports within 60 km of the path, in the three hours either side.

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

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

4 more were confirmed in the United States that day.

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.

NOAA Storm Prediction Center tornado database, 1950-2025, the official record kept by NOAA's Storm Prediction Center.