Tornadoes · United States · North Dakota · 2020

Unrated tornado, Ellendale Arpt, North Dakota, June 20, 2020

This Unrated tornado ran 0.3 miles across Dickey County on June 20, 2020, touching down at 5:25 PM CDT and reaching 30 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
June 20, 2020
Touchdown
5:25 PM CDT (22:25 UTC)
Lifted
5:26 PM CDT (22:26 UTC)
On the ground
1 minutes
Path length
0.3 miles (0.4 km)
Path width
30 yards (27 m)
Deaths
0
Injuries
0
County
Dickey County
Touchdown point
46.020, -98.450
Lift-off point
46.022, -98.445
Record number
2006201625-01

What the Weather Service recorded

Thunderstorms developed along a surface trough over the James River Valley in modest instability. Multiple funnel clouds were reported over LaMoure and Dickey counties, with a tornado occurring near Ellendale. The tornado produced no damage to evaluate and so by National Weather Service policy was rated EF Unknown. In addition, one inch diameter hail occurred in LaMoure and Dickey counties.

The tornado touched down northeast of Ellendale. There was no damage to evaluate and so by National Weather Service policy the tornado is rated EF Unknown.

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.

Issued (UTC)ExpiredProductOffice
21:59 UTC22:45 UTCSevere Thunderstorm WarningBIS
22:38 UTC23:30 UTCSevere Thunderstorm WarningBIS

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. The outlook in force was issued at 20:01 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.

Aberdeen, SD (KABR), 12:00Z

10.4 hours before the tornado, 125 km from the path. June 20, 2020.

Skew-T log-pSkew-T log-p diagram, Aberdeen, SD at 12:00Z on 2020-06-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 1 joules per kilogram, CIN -146, lifted condensation level 1544 meters above ground. Wind barbs in knots down the right edge.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°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, Aberdeen, SD at 12:00Z on 2020-06-20The 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 99 square meters per square second, 0 to 6 km bulk shear 27 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
1 J/kg
Mixed-layer CIN
-146 J/kg
Surface CAPE
524 J/kg
Mixed-layer LCL
1544 m above ground
0-6 km bulk shear
27 kt
0-1 km bulk shear
15 kt
0-1 km storm-relative helicity
99 m²/s²
0-3 km storm-relative helicity
95 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.1
0-3 km lapse rate
6.2 K/km

Open this sounding in Storm Lab

Aberdeen, SD (KABR), 00:00Z

1.6 hours after it, 125 km from the path. June 21, 2020.

Skew-T log-pSkew-T log-p diagram, Aberdeen, SD at 00:00Z on 2020-06-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 708 joules per kilogram, CIN -41, lifted condensation level 1443 meters above ground. Wind barbs in knots down the right edge.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°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, Aberdeen, SD at 00:00Z on 2020-06-21The 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 109 square meters per square second, 0 to 6 km bulk shear 32 knots.193958Sfc1 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
708 J/kg
Mixed-layer CIN
-41 J/kg
Surface CAPE
2431 J/kg
Mixed-layer LCL
1443 m above ground
0-6 km bulk shear
32 kt
0-1 km bulk shear
16 kt
0-1 km storm-relative helicity
109 m²/s²
0-3 km storm-relative helicity
127 m²/s²
Significant tornado parameter
0.2
Supercell composite
4.3
0-3 km lapse rate
7.3 K/km

Open this sounding in Storm Lab

The radar

The Aberdeen radar (KABR), 63 km away, was scanning. The volume nearest the touchdown began at 22:24 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
21:25 UTCHAIL 17 Ne EdgeleyLamoure, NDALSO VERY STRONG WINDS ESTIMATED AT 60 TO 70 MPH.
21:49 UTCFUNNEL CLOUD3 Nw La MoureLamoure, NDTWITTER PHOTO AND VIDEO OF A BRIEF FUNNEL CLOUD. EXACT LOCATION ESTIMATED FROM RADAR VELOCITY DATA.
22:20 UTCHAIL 13 Ne EllendaleDickey, NDPHOTO OF QUARTER SIZED HAILSTONE RELAYED BY BROADCAST MEDIA. PHOTO WAS TAKEN AROUND 5:25 PM CDT.
22:25 UTCTORNADO4 Ene EllendaleDickey, NDDICKEY COUNTY EMERGENCY MANAGER REPORTED TWO BRIEF TOUCHDOWNS OF WEAK, ROPE TORNADOES. NO DAMAGE REPORTED. TIME ESTIMATED BASED ON RADAR VELOCITY DATA.
22:32 UTCFUNNEL CLOUD4 Wsw GuelphDickey, NDSPOTTER REPORTS THAT A BRIEF FUNNEL CLOUD REACHED HALF WAY TO THE GROUND LOOKING WEST FROM THE INTERSECTION OF STATE HIGHWAY 11 AND 105TH AVE. EXACT LOCATION OF FUNNEL ESTIMATED FROM RADAR VELOCITY DATA AT THE TIME OF RE
23:00 UTCFUNNEL CLOUD3 Ssw LuddenDickey, NDREPORT RELAYED BY NWS GRAND FORKS. FUNNEL MADE IT HALF WAY TO THE GROUND.

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 North DakotaEvery tornado in North Dakota since 1950Warnings in force in North Dakota nowThe forecast where you are

The other tornadoes of June 20, 2020

5 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
June 205:01 PM CDTEF0Winnebago, WI0.250
June 205:23 PM CDTEF0Winnebago, WI1.175
June 205:25 PM CDTEF0Blaine, NE0.010
June 205:35 PM CDTEF0Winnebago, WI3.475
June 208:09 PM CDTEF0Spink, SD0.210

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.