EF0 tornado, Wyoming, Minnesota, June 21, 2013

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

June 21, 2013

Touchdown

3:46 AM CDT (08:46 UTC)

Lifted

3:47 AM CDT (08:47 UTC)

On the ground

1 minutes

Path length

0.5 miles (0.8 km)

Path width

50 yards (46 m)

Deaths

0

Injuries

0

Property damage

$100,000

County

Chisago County

Touchdown point

45.326, -92.992

Lift-off point

45.328, -92.982

Record number

1306210246-01

5 damage points were recorded along this path by NWS MPX, in the Damage Assessment Toolkit the survey teams carry. The strongest indicator was rated EF0. The highest wind the damage implies is 80 mph.

• EF0 tornado with damage to trees and minor damage to shingles.
• Tornado End: EF0 with damage to trees and roofing.
• Tornado start: EF0 tornado with damage to trees and roofing of a house.
• Several pine trees either snapped or uprooted.

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

Several rounds of thunderstorms developed Thursday late afternoon and evening, June 20th, mostly in west central Minnesota, and moved eastward. These storms produced some penny to quarter size hail, but the main event was damaging straight line winds and torrential rainfall during the late evening and overnight period. These storms moved across central and east central Minnesota after midnight, with some redevelopment in far south central Minnesota toward daybreak. ||Flash flooding was observed in portions of west central and central Minnesota where locally three to five inches of rain fell in a short period of time. The towns of Morris, Glenwood, Starbuck, Sauk Centre and Long Prairie were the hardest hit with numerous flooded roadways. ||Wind damage came in two different waves, the first was associated with embedded bow-echoes that moved across central Minnesota, while the second wave came from outflow from previous thunderstorms.||Strong outflow winds from previous thunderstorms affected four counties in central Minnesota, producing a wide area of damage. Winds exceeded 40 mph for nearly two hours in portions of Todd and Stearns Counties. Peak gusts include 63 mph at Sauk Centre (Stearns County) at 0200, 60 mph in Clearwater (Wright County) at 0240, 55 mph at Rice (Benton County) at 0200, and 54 mph at Long Prairie (Todd County) at 0235. A business in Long Prairie lost a roof during the height of the high winds. Debris was blown to the south, landing on cars in a parking lot, and numerous trees were blown down around Long Prairie. Trees and power lines were downed across portions of Todd, Benton, Stearns and Wright Counties.

Dozens of trees were uprooted or snapped along a half mile long path around Ashton Lake in Wyoming. Some trees landed on houses, fences and sheds with the greatest damage on the northeast side of the lake.

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.

The county was under a severe thunderstorm watch, issued at 01:53 UTC and running to 10:18 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 05:55 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 Minneapolis radar (KMPX), 70 km away, was scanning. The volume nearest the touchdown began at 08:47 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 2013 tornado in MinnesotaEvery tornado in Minnesota since 1950Warnings in force in Minnesota nowThe forecast where you are

10 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.