Tornadoes · United States · Minnesota · 2020

EF0 tornado, Vining, Minnesota, July 8, 2020

This EF0 tornado ran 0.2 miles across Otter Tail County on July 8, 2020, touching down at 6:32 PM CDT and reaching 20 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
July 8, 2020
Touchdown
6:32 PM CDT (23:32 UTC)
Lifted
6:33 PM CDT (23:33 UTC)
On the ground
1 minutes
Path length
0.2 miles (0.3 km)
Path width
20 yards (18 m)
Deaths
0
Injuries
0
County
Otter Tail County
Touchdown point
46.240, -95.520
Lift-off point
46.240, -95.520
Record number
2007081732-01

What the Weather Service recorded

A lone weak cell appeared on radar at 430 pm CDT over northern Grant County, Minnesota. Numerous storm chasers had congregated in this area, hoping to see a good storm to chase. By 5 pm, the cell had blossomed into a strong thunderstorm. Weather spotters, law enforcement, and storm chasers then reported a funnel coming down toward the ground slightly after 505 pm. A tornado warning was issued at 508 pm (until 6 pm) for portions of south central Otter Tail and northeast Grant counties. This tornado tracked about 9 miles through the warned area, before dissipating. At its peak strength, it was rated as an EF-4 tornado. Another rotation was noted a little later, leading to a second tornado warning at 635 pm (until 7 pm), this time for southwest Wadena and southeast Otter Tail counties.

A persistent funnel cloud briefly touched down. Peak winds were estimated at 75 mph.

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 21:15 UTC and running to 05:00 UTC.

Issued (UTC)ExpiredProductOffice
07:13 UTC11:00 UTCSevere Thunderstorm WatchFGF
08:58 UTC10:00 UTCSevere Thunderstorm WarningFGF
09:14 UTC09:45 UTCTornado WarningFGF
09:43 UTC10:30 UTCTornado WarningFGF
10:00 UTC10:45 UTCSevere Thunderstorm WarningFGF
10:20 UTC11:00 UTCTornado WarningFGF
10:53 UTC11:20 UTCSevere Thunderstorm WarningFGF
21:15 UTC05:00 UTCSevere Thunderstorm WatchFGF
22:08 UTC23:00 UTCTornado WarningFGF
23:35 UTC00:00 UTCTornado WarningFGF
04:27 UTC04:58 UTCSevere Thunderstorm WarningFGF
04:38 UTC05:30 UTCSevere Thunderstorm WarningFGF

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 Slight Risk, with a 0.02 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.

Minneapolis, MN (KMPX), 12:00Z

11.5 hours before the tornado, 215 km from the path. July 8, 2020.

Skew-T log-pSkew-T log-p diagram, Minneapolis, MN at 12:00Z on 2020-07-08Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 1297 joules per kilogram, CIN -141, lifted condensation level 1096 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, Minneapolis, MN at 12:00Z on 2020-07-08The 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 163 square meters per square second, 0 to 6 km bulk shear 19 knots.1939Sfc1 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
1297 J/kg
Mixed-layer CIN
-141 J/kg
Surface CAPE
1094 J/kg
Mixed-layer LCL
1096 m above ground
0-6 km bulk shear
19 kt
0-1 km bulk shear
23 kt
0-1 km storm-relative helicity
163 m²/s²
0-3 km storm-relative helicity
291 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0
0-3 km lapse rate
4.4 K/km

Open this sounding in Storm Lab

Minneapolis, MN (KMPX), 00:00Z

0.5 hours after it, 215 km from the path. July 9, 2020.

Skew-T log-pSkew-T log-p diagram, Minneapolis, MN at 00:00Z on 2020-07-09Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 2332 joules per kilogram, CIN -31, lifted condensation level 1764 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, Minneapolis, MN at 00:00Z on 2020-07-09The 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 34 square meters per square second, 0 to 6 km bulk shear 14 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
2332 J/kg
Mixed-layer CIN
-31 J/kg
Surface CAPE
4633 J/kg
Mixed-layer LCL
1764 m above ground
0-6 km bulk shear
14 kt
0-1 km bulk shear
20 kt
0-1 km storm-relative helicity
34 m²/s²
0-3 km storm-relative helicity
131 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0
0-3 km lapse rate
8.0 K/km

Open this sounding in Storm Lab

The surface observations

Wadena Municipal (ADC), 33 km from the path, in the two hours either side.

Time (UTC)Temp (°F)Dew point (°F)WindGust (kt)Pressure (mb)Weather
21:35 UTC82.471.6180° 5 kt1007.5
21:55 UTC84.271.6170° 4 kt1007.1
21:56 UTC84.271.6190° 5 kt1007.1
22:15 UTC82.471.60° 0 kt1006.8
22:35 UTC80.673.40° 0 kt1006.8VCTS
22:55 UTC80.675.20° 0 kt1007.1
22:56 UTC78.875.20° 0 kt1006.8
23:15 UTC78.875.270° 5 kt1006.4-RA
23:35 UTC78.873.430° 5 kt1006.1-TSRA
23:55 UTC80.673.480° 3 kt1006.8-VCTSRA
23:56 UTC80.673.40° 0 kt1006.8-VCTSRA
00:15 UTC80.673.40° 0 kt1006.1-TSRA
00:16 UTC80.673.40° 0 kt1006.1-TSRA
00:35 UTC80.673.440° 3 kt1005.8VCTS
00:36 UTC80.673.450° 3 kt1005.8VCTS
00:55 UTC80.673.40° 0 kt1005.8
00:56 UTC80.673.40° 0 kt1005.8
01:15 UTC78.873.430° 4 kt1005.8
01:16 UTC78.873.440° 4 kt1006.1

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

The radar

The Fargo/Grand Forks radar (KMVX), 198 km away, was scanning. The volume nearest the touchdown began at 23:32 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 UTCTORNADO 46 W AshbyGrant, MNTHIS TORNADO TRACKED NE FOR ROUGHLY 9 MILES, FROM EXTREME NE POMME DE TERRE TOWNSHIP ACROSS EXTREME SE TUMULI TOWNSHIP AND SW ST. OLAF TOWNSHIPS OF OTTER TAIL COUNTY. IT LIFTED ABOUT 5 E DALTON BY 539 PM CDT. THE TORNADO
22:11 UTCTORNADO6 Sw DaltonOtter Tail, MNLARGE TORNADO ON THE GROUND, HEADING TOWARD A FARMHOUSE.
22:19 UTCTORNADO6 S DaltonGrant, MNLARGE TORNADO ON THE GROUND. ONE-HALF MILE FROM INTERSTATE REST AREA. SEEING DEBRIS LOFTED IN THE AIR.
22:30 UTCTORNADO5 Ese DaltonOtter Tail, MN3 FARMSTEADS HAVE BEEN HIT. TORNADO CURRENTLY AT 295TH AND STATE HIGHWAY 82. TORNADO CROSSED I-94, BUT NO VEHICLES WERE AFFECTED.
22:40 UTCTSTM WND DMG3 N OttertailOtter Tail, MNMULTIPLE TREES WERE BLOWN DOWN.
22:40 UTCTSTM WND DMG3 N OttertailOtter Tail, MNMULTIPLE TREES DOWN.
23:32 UTCTORNADO 02 Sse ViningOtter Tail, MNA PERSISTENT FUNNEL CLOUD WITH BRIEF TOUCHDOWN WAS VIEWED BY SEVERAL STORM SPOTTERS. IT LIKELY TRACKED FOR LESS THAN ONE-QUARTER MILE AND LIFTED BY 633 OM CDT. ESTMATED WIDTH TO 20 YARDS AND PEAK WINDS TO 75 MPH.
23:34 UTCTORNADO2 Ese ViningOtter Tail, MNBRIEF TORNADO REPORTED BY CHASERS.
00:20 UTCFUNNEL CLOUD3 W WrightstownOtter Tail, MNA PERSISTENT WALL CLOUD WITH SUSTAINED FUNNEL WAS VIEWED BY SEVERAL STORM SPOTTERS AS IT MOVED ACROSS NORTHWEST WOODSIDE TOWNSHIP.

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

This ground now

The live radar over the trackEvery 2020 tornado in MinnesotaEvery tornado in Minnesota since 1950Warnings in force in Minnesota nowThe forecast where you are

The other tornadoes of July 8, 2020

17 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
July 84:20 AM CDTEF1Wilkin, MN12.4200$550,000
July 84:38 AM CDTEF1Otter Tail, MN18.7250$750,000
July 85:10 AM CDTEF2Otter Tail, MN2.0300$200,000
July 84:04 PM CDTUnratedWhiteside, IL0.310
July 85:08 PM CDTEF4Ashby–Dalton tornado, MN8.965012$1.6 million
July 85:49 PM MDTEF0Sedgwick, CO0.050
July 85:50 PM MDTUnratedPerkins, NE0.110
July 85:55 PM MDTUnratedPerkins, NE0.110
July 85:59 PM MDTEF0Sedgwick, CO0.050
July 86:01 PM MDTUnratedPerkins, NE0.110
July 86:04 PM MDTEF0Sedgwick, CO0.050
July 86:04 PM MDTEF0Phillips, CO0.050
July 86:10 PM MDTEF0Sedgwick, CO0.050
July 87:15 PM CDTEF0Crow Wing, MN7.450$10,000
July 86:19 PM MDTEF0Sedgwick, CO0.050
July 87:55 PM CDTUnratedThomas, NE0.110
July 811:29 PM CDTEF0Merrick, NE4.2130$200,000

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.