Tornadoes · United States · Nebraska · 2011
EF0 tornado, Ewing, Nebraska, August 18, 2011
This EF0 tornado ran 0.0 miles across Holt County on August 18, 2011, touching down at 5:23 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.
EF065 to 85 mphthis tornado
Light damage. Surface peeled off some roofs, gutters and siding damaged, branches broken, shallow-rooted trees pushed over.
EF186 to 110 mph
Moderate damage. Roofs badly stripped, mobile homes overturned or badly damaged, exterior doors lost, windows broken.
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.
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.
EF4166 to 200 mph
Devastating damage. Well-built houses leveled, structures with weak foundations moved some distance, cars thrown and large missiles generated.
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.
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
- August 18, 2011
- Touchdown
- 5:23 PM CDT (22:23 UTC)
- Lifted
- 5:24 PM CDT (22:24 UTC)
- On the ground
- 1 minutes
- Path length
- 0.0 miles (0.0 km)
- Path width
- 20 yards (18 m)
- Deaths
- 0
- Injuries
- 0
- County
- Holt County
- Touchdown point
- 42.285, -98.350
- Lift-off point
- 42.284, -98.349
- Record number
- 1108181623-01
What the Weather Service recorded
Several intense severe thunderstorms developed on the afternoon of August 18th over north central Nebraska. These storms became anchored on a boundary which resulted in slow storm motions and enhanced the rotation in the storms. Very large hail up to baseball size fell from these storms, while they also produced funnel clouds and tornadoes near Ewing (eastern Holt county). In addition, another isolated thunderstorm dropped ping pong size hail over northwest Cherry county in the early evening hours.
There was a brief tornado touchdown just north of Ewing. As the storm moved over Ewing the entire storm exhibited massive rotation. No damage occurred from this tornado and it was rated as an EF0 tornado.
A tornado touched down just southeast of Ewing near the Holt county and Antelope county line. It was on the ground for one minute with no damage observed. At the time of the report, the tornado was large and was becoming rain wrapped.
From NOAA NCEI's Storm Events Database, the narrative the local forecast office wrote for Storm Data.
The warnings
4 minutes of warning. NWS LBF issued a tornado warning for this county at 22:19 UTC, 4 minutes before the tornado touched down, in force until 22:45 UTC.
| Issued (UTC) | Expired | Product | Office |
|---|---|---|---|
| 21:43 UTC | 22:30 UTC | Severe Thunderstorm Warning | LBF |
| 21:54 UTC | 23:00 UTC | Severe Thunderstorm Warning | LBF |
| 22:19 UTC | 22:45 UTC | Tornado Warning | LBF |
| 22:25 UTC | 23:15 UTC | Severe Thunderstorm Warning | LBF |
| 22:53 UTC | 23:30 UTC | Tornado Warning | LBF |
| 23:48 UTC | 03:50 UTC | Tornado Watch | LBF |
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 19:44 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), 12:00Z
10.4 hours before the tornado, 196 km from the path. August 18, 2011.
- Mixed-layer CAPE
- 1181 J/kg
- Mixed-layer CIN
- -126 J/kg
- Surface CAPE
- 273 J/kg
- Mixed-layer LCL
- 683 m above ground
- 0-6 km bulk shear
- 47 kt
- 0-1 km bulk shear
- 20 kt
- 0-1 km storm-relative helicity
- 234 m²/s²
- 0-3 km storm-relative helicity
- 385 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 11.7
- 0-3 km lapse rate
- 3.9 K/km
Omaha, NE (KOAX), 00:00Z
1.6 hours after it, 196 km from the path. August 19, 2011.
- Mixed-layer CAPE
- 1385 J/kg
- Mixed-layer CIN
- -135 J/kg
- Surface CAPE
- 295 J/kg
- Mixed-layer LCL
- 582 m above ground
- 0-6 km bulk shear
- 66 kt
- 0-1 km bulk shear
- 25 kt
- 0-1 km storm-relative helicity
- 289 m²/s²
- 0-3 km storm-relative helicity
- 636 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 47.4
- 0-3 km lapse rate
- 4.2 K/km
The surface observations
O Neill (ONL), 35 km from the path, in the two hours either side.
| Time (UTC) | Temp (°F) | Dew point (°F) | Wind | Gust (kt) | Pressure (mb) | Weather |
|---|---|---|---|---|---|---|
| 20:35 UTC | 78.8 | 69.8 | 100° 14 kt | 19 | 1010.5 | |
| 20:55 UTC | 80.6 | 69.8 | 100° 14 kt | 20 | 1010.2 | |
| 21:15 UTC | 80.6 | 71.6 | 100° 7 kt | 1010.2 | ||
| 21:35 UTC | 80.6 | 71.6 | 100° 11 kt | 16 | 1009.8 | VCTS |
| 21:55 UTC | 80.6 | 71.6 | 90° 15 kt | 18 | 1009.5 | |
| 22:15 UTC | 80.6 | 71.6 | 90° 13 kt | 1008.8 | VCTS | |
| 22:35 UTC | 80.6 | 71.6 | 80° 15 kt | 18 | 1009.1 | TS |
| 22:55 UTC | 80.6 | 71.6 | 60° 15 kt | 18 | 1009.5 | VCTS |
| 23:15 UTC | 78.8 | 69.8 | 50° 10 kt | 1009.5 | VCTS | |
| 23:35 UTC | 78.8 | 69.8 | 70° 11 kt | 1008.8 | VCTS | |
| 23:55 UTC | 78.8 | 69.8 | 110° 9 kt | 1008.5 | TS | |
| 00:15 UTC | 77 | 69.8 | 90° 18 kt | 22 | 1008.5 | VCTS |
From the Iowa Environmental Mesonet's archive of airport observations.
The radar
The North Platte radar (KLNX), 187 km away, was scanning. The volume nearest the touchdown began at 22:22 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) | Report | Where | County | Remark |
|---|---|---|---|---|
| 21:43 UTC | HAIL 1 | 3 Se Inman | Holt, NE | HAIL FALLING AT THE TIME OF THE REPORT. |
| 22:01 UTC | HAIL 2 | 2 N Ewing | Holt, NE | |
| 22:09 UTC | HAIL 2 | 1 E Ewing | Holt, NE | |
| 22:13 UTC | HAIL 1.5 | 5 Sse Bristow | Holt, NE | |
| 22:13 UTC | HAIL 2.5 | 1 N Ewing | Holt, NE | GOLF BALL TO TENNIS BALL SIZE HAIL ALONG HIGHWAY 45B. |
| 22:13 UTC | TORNADO | 3 Se Ewing | Holt, NE | LARGE TORNADO SPOTTED NEAR THE COUNTY LINE BECOMING RAIN WRAPPED. |
| 22:15 UTC | FUNNEL CLOUD | 3 Nnw Ewing | Holt, NE | INITIAL FUNNEL CLOUD DISSIPATED WITH ANOTHER FORMING. |
| 22:23 UTC | TORNADO | 1 N Ewing | Holt, NE | FUNNEL CLOUD BRIEFLY TOUCHED DOWN AND THEN WENT RIGHT BACK UP. THE STORM WAS EXHIBITING MASSIVE ROTATION OVER EWING. |
| 22:45 UTC | HAIL 1.75 | 14 Ne Oneill | Holt, NE | |
| 22:46 UTC | TORNADO | 3 W Clearwater | Antelope, NE | TORNADO ABOUT 3 MILES WEST OF CLEARWATER ON THE GROUND ABOUT ONE MILE. EVENT TIME ESTIMATED 546 PM TO 550 PM. |
| 22:48 UTC | TORNADO | 3 Se Ewing | Holt, NE | LARGE TORNADO SPOTTED NEAR THE COUNTY LINE BECOMING RAIN WRAPPED. |
| 23:03 UTC | TORNADO | Clearwater | Antelope, NE | |
| 23:06 UTC | HAIL 2.75 | 4 Nne Page | Holt, NE | |
| 23:20 UTC | HAIL 1.75 | 9 N Orchard | Knox, NE | |
| 23:30 UTC | TORNADO | Clearwater | Antelope, NE | |
| 23:45 UTC | HAIL 1 | Oakdale | Antelope, NE | LASTED 15 MINUTES. |
| 00:23 UTC | HAIL 0.88 | Tilden | Antelope, NE |
From the Iowa Environmental Mesonet's archive of National Weather Service local storm reports.
This ground now
The live radar over the trackEvery 2011 tornado in NebraskaEvery tornado in Nebraska since 1950Warnings in force in Nebraska nowThe forecast where you are
The other tornadoes of August 18, 2011
5 more were confirmed in the United States that day.
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.