EF0 tornado, (Den)Denver Intl Arp, Colorado, May 26, 2010

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.

Rating

EF0

Date

May 26, 2010

Touchdown

1:30 PM MDT (19:30 UTC)

Lifted

1:39 PM MDT (19:39 UTC)

On the ground

9 minutes

Path length

0.1 miles (0.2 km)

Path width

50 yards (46 m)

Deaths

0

Injuries

0

County

Denver County

Touchdown point

39.850, -104.821

Lift-off point

39.850, -104.821

Record number

1005261330-01

Severe thunderstorms pounded parts the Urban Corridor and Northeast Plains with very large hail, damaging wind and tornadoes. The hail, ranging from golfball to baseball size, hit northeast Denver, Brighton and Commerce City the hardest. The storms then continued to spread to the north and east; impacting Hudson, Prospect Valley, Byers and Deer Trail. The strong thunderstorm wind and hail stripped bark and branches from trees. Numerous accidents were reported as the hail accumulated up to a foot in depth on roadways. Homes and vehicles in the area were pummeled by hail. The Rocky Mountain Insurance Information Associated estimated to damage to be around $70 million; based off approximately 13,600 automobile and homeowner claims. A child in Commerce City was struck in the leg by lightning while watching televison. A bison and the Rocky Mountain Arsenal National Wildlife Refuge was struck and killed by blast of lightning. Two tornadoes also touched down in open country; one near Denver International Airport and the other near Keenesburg. ||The heavy rain and hail caused flash flooding to occur around the towns of Hudson and Keenseburg; forcing the closure of State Highway 52. Extensive crop damage was reported across southern Weld County. Approximately 1500 acres of sugar beets were damaged in the Prospect Valley and Windsor areas. About 360 acres of sweet corn, cabbage and onions in the Hudson area were inundated with heavy rain and a torrent of hail. In Windsor, a barn was demolished by intense thunderstorm winds. The wind ripped the 40-ft by 40-ft structure of a garage and exterior corrugated roof and walls about 75 yards from its original foundation. Also, two cow shelters and 150 calf shelters were blown over. Near Bellvue, several structures were knocked down and a 15-ft silo was blown across a field by damaging thunderstorm winds.

A tornado touched down but did no damage.

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

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.

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 General Thunderstorms Risk, with a 0.02 chance of a tornado within 25 miles. The outlook in force was issued at 16:47 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.

The Denver radar (KFTG), 25 km away, was scanning. The volume nearest the touchdown began at 19:28 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 2010 tornado in ColoradoEvery tornado in Colorado since 1950Warnings in force in Colorado nowThe forecast where you are

3 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.