Tornadoes · United States · Nebraska · 2018

EF0 tornado, Elk Creek, Nebraska, June 11, 2018

This EF0 tornado ran 0.1 miles across Johnson County on June 11, 2018, touching down at 8:00 PM CDT and reaching 25 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
June 11, 2018
Touchdown
8:00 PM CDT (01:00 UTC)
Lifted
8:02 PM CDT (01:02 UTC)
On the ground
2 minutes
Path length
0.1 miles (0.1 km)
Path width
25 yards (23 m)
Deaths
0
Injuries
0
County
Johnson County
Touchdown point
40.327, -96.096
Lift-off point
40.327, -96.095
Record number
1806111900-01

The damage survey

3 damage points were recorded along this path by NWS OAX, in the Damage Assessment Toolkit the survey teams carry. The strongest indicator was rated EF0. The highest wind the damage implies is 74 mph.

  • 40.222996, -96.172481 actual lat
  • Brief touchdown in middle of field.

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

What the Weather Service recorded

A weak upper-level disturbance tracked from the central High Plains through the mid Missouri Valley, encouraging the development of a surface low from southeast South Dakota into eastern Nebraska. Meanwhile, an associated cold front progressed east into eastern Nebraska by afternoon with a stationary boundary extending from the surface low through southwest Iowa into northern Missouri. Severe thunderstorms developed during the late afternoon over eastern Nebraska and southwest Iowa along these surface features with activity merging into a bow-echo complex that subsequently tracked into northwest Missouri by late evening. Brief tornadoes occurred with a supercell over Cass County, NE with intense, straight-line winds affecting the I-29 corridor in Fremont County, IA.

A short lived tornado that produced minor tree branch damage and was over a field for part of its path. It traveled for less than a tenth of a mile moving west to east and was located 3 3/4 north northeast of Elk Creek.

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

The warnings

14 minutes of warning. NWS OAX issued a tornado warning for this county at 00:46 UTC, 14 minutes before the tornado touched down, in force until 01:15 UTC.

The county was under a tornado watch, issued at 20:49 UTC and running to 02:31 UTC.

Issued (UTC)ExpiredProductOffice
20:49 UTC02:31 UTCTornado WatchOAX
23:35 UTC00:30 UTCSevere Thunderstorm WarningOAX
00:27 UTC01:00 UTCSevere Thunderstorm WarningOAX
00:46 UTC01:15 UTCTornado WarningOAX
00:53 UTC01:33 UTCSevere Thunderstorm WarningOAX

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 Enhanced Risk, with a 0.02 chance of a tornado within 25 miles. The outlook in force was issued at 00:45 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.

Omaha, NE (KOAX), 00:00Z

1.0 hours before the tornado, 113 km from the path. June 12, 2018.

Skew-T log-pSkew-T log-p diagram, Omaha, NE at 00:00Z on 2018-06-12Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 562 joules per kilogram, CIN -153, lifted condensation level 1301 meters above ground. Wind barbs in knots down the right edge.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 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, Omaha, NE at 00:00Z on 2018-06-12The 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 52 square meters per square second, 0 to 6 km bulk shear 37 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
562 J/kg
Mixed-layer CIN
-153 J/kg
Surface CAPE
538 J/kg
Mixed-layer LCL
1301 m above ground
0-6 km bulk shear
37 kt
0-1 km bulk shear
5 kt
0-1 km storm-relative helicity
52 m²/s²
0-3 km storm-relative helicity
117 m²/s²
Significant tornado parameter
0.0
Supercell composite
3.0
0-3 km lapse rate
5.3 K/km

Open this sounding in Storm Lab

Omaha, NE (KOAX), 12:00Z

11.0 hours after it, 113 km from the path. June 12, 2018.

Skew-T log-pSkew-T log-p diagram, Omaha, NE at 12:00Z on 2018-06-12Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 325 joules per kilogram, CIN -303, lifted condensation level 913 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, Omaha, NE at 12:00Z on 2018-06-12The 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 -1 square meters per square second, 0 to 6 km bulk shear 29 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
325 J/kg
Mixed-layer CIN
-303 J/kg
Surface CAPE
66 J/kg
Mixed-layer LCL
913 m above ground
0-6 km bulk shear
29 kt
0-1 km bulk shear
20 kt
0-1 km storm-relative helicity
-1 m²/s²
0-3 km storm-relative helicity
-88 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0
0-3 km lapse rate
3.4 K/km

Open this sounding in Storm Lab

The surface observations

Nebraska City (AFK), 37 km from the path, in the two hours either side.

Time (UTC)Temp (°F)Dew point (°F)WindGust (kt)Pressure (mb)Weather
23:15 UTC8777150° 8 kt1004.4VCTS
23:35 UTC86.276170° 8 kt1003VCTS
23:55 UTC8674150° 6 kt1002.4TS
00:20 UTC
00:35 UTC6463.7320° 9 kt321009.5+TSRA
00:55 UTC66.76480° 5 kt1009.5+TSRA
01:15 UTC68.462.8180° 7 kt1007.1-VCTSRA
01:35 UTC65.364.2100° 14 kt211008.5TS
01:55 UTC65.865.8100° 15 kt201008.5VCTS
02:15 UTC67.367130° 6 kt141008.1VCTS
02:35 UTC67.366.7160° 12 kt1008.8
02:55 UTC6766.2170° 11 kt1009.1

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

The radar

The Omaha radar (KOAX), 113 km away, was scanning. The volume nearest the touchdown began at 00:57 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
23:41 UTCHAIL 1.75ElmwoodCass, NE
00:05 UTCTSTM WND GST 803 E UnionCass, NEPERSONAL WEATHER STATION
00:15 UTCTSTM WND DMGNebraska CityOtoe, NETREE BRANCHES BLOWN ONTO ROAD.
00:16 UTCHAIL 1.253 E SterlingJohnson, NE
00:18 UTCTSTM WND GST 631 E TalmageOtoe, NE
00:21 UTCHAIL 11 S TecumsehJohnson, NE
00:21 UTCHAIL 1SterlingJohnson, NE
00:30 UTCTSTM WND GST 50BrockNemaha, NE
00:33 UTCHAIL 1.755 W TecumsehJohnson, NE
00:35 UTCHAIL 2CookJohnson, NE
00:40 UTCHAIL 12 Sse CookJohnson, NE
00:45 UTCHAIL 2.758 S CookJohnson, NE
01:01 UTCFUNNEL CLOUD5 Ese Elk CreekNemaha, NE
01:05 UTCTORNADOTable RockPawnee, NE
01:13 UTCHAIL 2.54 N SteinauerJohnson, NE
01:19 UTCHAIL 11 E Table RockPawnee, NE
01:40 UTCHAIL 1HumboldtRichardson, NE

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

This ground now

The live radar over the trackEvery 2018 tornado in NebraskaEvery tornado in Nebraska since 1950Warnings in force in Nebraska nowThe forecast where you are

The other tornadoes of June 11, 2018

5 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
June 115:40 PM CDTEF0Cass, NE0.110
June 116:30 PM CDTEF0Cass, NE0.375
June 116:32 PM CDTEF0Cass, NE0.320
June 116:59 PM CDTEF0Fremont, IA0.110
June 118:05 PM CDTEF0Pawnee, NE0.020

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.