Tornadoes · United States · North Dakota · 2008
EF0 tornado, Voltaire to Balfour, North Dakota, August 11, 2008
From Voltaire to Balfour, this EF0 tornado ran 1.0 miles across McHenry County on August 11, 2008, touching down at 4:25 PM CDT and reaching 35 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 11, 2008
- Touchdown
- 4:25 PM CDT (21:25 UTC)
- Lifted
- 4:27 PM CDT (21:27 UTC)
- On the ground
- 2 minutes
- Path length
- 1.0 miles (1.6 km)
- Path width
- 35 yards (32 m)
- Deaths
- 0
- Injuries
- 0
- County
- McHenry County
- Touchdown point
- 48.090, -100.605
- Lift-off point
- 48.080, -100.589
- Record number
- 0808111525-01
What the Weather Service recorded
During the afternoon hours of August 11th, five tornadoes occurred in central North Dakota, across Burleigh, Sheridan, and McHenry counties. These tornadoes were the result of a localized area of sufficient low level buoyancy and low level vorticity coincident over central North Dakota. A surface cold front stretched north to south across the central plains. All of the five tornadoes remained in open country and impacted no structures. As a result, they were rated EF0 on the Enhanced Fujita Scale.
The public reported this tornado as being briefly on the ground. There was no damage and no reports of structures being impacted.
The public reported this brief touchdown of a tornado. There were no reports of damage as this tornado remained in open field.
This tornado remained in open field and impacted no structures. No damage was reported.
From NOAA NCEI's Storm Events Database, the narrative the local forecast office wrote for Storm Data.
The warnings
2 minutes of warning. NWS BIS issued a tornado warning for this county at 21:23 UTC, 2 minutes before the tornado touched down, in force until 22:00 UTC.
| Issued (UTC) | Expired | Product | Office |
|---|---|---|---|
| 09:00 UTC | 00:00 UTC | Flash Flood Watch | BIS |
| 21:23 UTC | 22:00 UTC | Tornado Warning | BIS |
| 21:45 UTC | 22:15 UTC | Tornado Warning | BIS |
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 General Thunderstorms Risk. The outlook in force was issued at 20:06 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.
Bismarck Municip, ND (KBIS), 12:00Z
9.4 hours before the tornado, 146 km from the path. August 11, 2008.
- Mixed-layer CAPE
- 830 J/kg
- Mixed-layer CIN
- -41 J/kg
- Surface CAPE
- 610 J/kg
- Mixed-layer LCL
- 880 m above ground
- 0-6 km bulk shear
- 19 kt
- 0-1 km bulk shear
- 5 kt
- 0-1 km storm-relative helicity
- -9 m²/s²
- 0-3 km storm-relative helicity
- 39 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.3
- 0-3 km lapse rate
- 5.4 K/km
Bismarck Municip, ND (KBIS), 00:00Z
2.6 hours after it, 146 km from the path. August 12, 2008.
- Mixed-layer CAPE
- 911 J/kg
- Mixed-layer CIN
- -31 J/kg
- Surface CAPE
- 1980 J/kg
- Mixed-layer LCL
- 1258 m above ground
- 0-6 km bulk shear
- 21 kt
- 0-1 km bulk shear
- 22 kt
- 0-1 km storm-relative helicity
- -22 m²/s²
- 0-3 km storm-relative helicity
- 21 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- -0.4
- 0-3 km lapse rate
- 6.2 K/km
The surface observations
Minot_intl (MOT), 54 km from the path, in the two hours either side.
| Time (UTC) | Temp (°F) | Dew point (°F) | Wind | Gust (kt) | Pressure (mb) | Weather |
|---|---|---|---|---|---|---|
| 19:54 UTC | 73 | 64 | 240° 6 kt | 1009.1 | ||
| 20:54 UTC | 65 | 58 | 300° 17 kt | 23 | 1009.5 | |
| 21:01 UTC | 62.6 | 57.2 | 300° 16 kt | 23 | 1009.5 | RA |
| 21:08 UTC | 62.6 | 60.8 | 310° 9 kt | 21 | 1009.1 | +RA FG |
| 21:19 UTC | 62.6 | 60.8 | 360° 4 kt | 1008.8 | -RA BR | |
| 21:23 UTC | 64.4 | 62.6 | 350° 5 kt | 1008.8 | -RA BR | |
| 21:54 UTC | 69 | 64 | 320° 10 kt | 1008.5 | ||
| 22:54 UTC | 72 | 63 | 310° 9 kt | 1009.1 |
From the Iowa Environmental Mesonet's archive of airport observations.
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 |
|---|---|---|---|---|
| 21:20 UTC | TORNADO | 5 E Voltaire | Mchenry, ND | BRIEF TOUCHDOWN |
| 21:25 UTC | TORNADO | 1 Se Karlsruhe | Mchenry, ND | BRIEF TOUCHDOWN, THEN DISSIPATED |
| 21:48 UTC | TORNADO | 4 Sw Balfour | Mchenry, ND |
From the Iowa Environmental Mesonet's archive of National Weather Service local storm reports.
This ground now
The live radar over the trackEvery 2008 tornado in North DakotaEvery tornado in North Dakota since 1950Warnings in force in North Dakota nowThe forecast where you are
The other tornadoes of August 11, 2008
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.