Tornadoes · United States · North Dakota · 2023
Unrated tornado, Voltaire, North Dakota, August 24, 2023
This Unrated tornado ran 0.8 miles across McHenry County on August 24, 2023, touching down at 2:38 PM CDT and reaching 50 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 mph
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.
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
- August 24, 2023
- Touchdown
- 2:38 PM CDT (19:38 UTC)
- Lifted
- 2:42 PM CDT (19:42 UTC)
- On the ground
- 4 minutes
- Path length
- 0.8 miles (1.3 km)
- Path width
- 50 yards (46 m)
- Deaths
- 0
- Injuries
- 0
- County
- McHenry County
- Touchdown point
- 47.960, -100.820
- Lift-off point
- 47.961, -100.803
- Record number
- 2308241338-01
What the Weather Service recorded
A cold front dropped slowly through North Dakota as an upper level low moved across southern Saskatchewan, with severe thunderstorms developing along and ahead of the front. Along one boundary ahead of the front, in the Voltaire area of McHenry County, two short-lived landspout tornadoes formed. No damage was reported with the tornadoes and so by National Weather Service policy the tornadoes were rated EF Unknown. The tornadoes touched down 12 minutes apart from two different thunderstorms. Otherwise, damaging thunderstorm winds were the main threat with most of the storms, though one storm produced one-inch diameter hail near Bottineau in Bottineau County. The strongest wind gust was estimated to be 75 mph, and occurred near Twin Buttes in Dunn County, where a truck window was broken out and a snowmobile trailer was blown down a coulee.
This tornado, a landspout, touched down in an open field south-southeast of Voltaire and impacted no structures. There was no damage to evaluate and so by National Weather Service policy the tornado is rated EF Unknown. This was the first of two landspout tornadoes in the Voltaire area of McHenry County this day, 12 minutes apart, from two different thunderstorms.
This tornado, a landspout, touched down in an open field southwest of Voltaire and impacted no structures. There was no damage to evaluate and so by National Weather Service policy the tornado is rated EF Unknown. This was the second of two landspout tornadoes in the Voltaire area of McHenry County this day, 12 minutes apart, from two different thunderstorms.
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.
| Issued (UTC) | Expired | Product | Office |
|---|---|---|---|
| 01:43 UTC | 02:10 UTC | Severe Thunderstorm Warning | BIS |
| 07:22 UTC | 15:00 UTC | Dense Fog Advisory | BIS |
| 19:41 UTC | 20:15 UTC | Tornado Warning | BIS |
| 19:45 UTC | 01:00 UTC | Severe Thunderstorm Watch | BIS |
| 19:55 UTC | 20:09 UTC | Tornado Warning | BIS |
| 21:09 UTC | 22:00 UTC | Severe Thunderstorm Warning | BIS |
| 21:52 UTC | 22:22 UTC | Severe Thunderstorm 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 Marginal Risk. The outlook in force was issued at 16:30 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
7.6 hours before the tornado, 133 km from the path. August 24, 2023.
- Mixed-layer CAPE
- 66 J/kg
- Mixed-layer CIN
- -234 J/kg
- Surface CAPE
- 0 J/kg
- Mixed-layer LCL
- 1667 m above ground
- 0-6 km bulk shear
- 45 kt
- 0-1 km bulk shear
- 13 kt
- 0-1 km storm-relative helicity
- -63 m²/s²
- 0-3 km storm-relative helicity
- -116 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- -0.0
- 0-3 km lapse rate
- 3.4 K/km
Bismarck Municip, ND (KBIS), 00:00Z
4.4 hours after it, 133 km from the path. August 25, 2023.
- Mixed-layer CAPE
- 542 J/kg
- Mixed-layer CIN
- -18 J/kg
- Surface CAPE
- 2111 J/kg
- Mixed-layer LCL
- 2128 m above ground
- 0-6 km bulk shear
- 56 kt
- 0-1 km bulk shear
- 12 kt
- 0-1 km storm-relative helicity
- 77 m²/s²
- 0-3 km storm-relative helicity
- 233 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 3.5
- 0-3 km lapse rate
- 9.0 K/km
The surface observations
Minot_intl (MOT), 48 km from the path, in the two hours either side.
| Time (UTC) | Temp (°F) | Dew point (°F) | Wind | Gust (kt) | Pressure (mb) | Weather |
|---|---|---|---|---|---|---|
| 17:40 UTC | 110° 2 kt | 1013.9 | ||||
| 17:45 UTC | 140° 2 kt | 1013.5 | ||||
| 17:50 UTC | 140° 4 kt | 1013.5 | ||||
| 17:54 UTC | 84 | 69 | 130° 3 kt | 1013.5 | VCTS | |
| 17:55 UTC | 130° 2 kt | 1013.5 | ||||
| 18:00 UTC | 180° 2 kt | 1013.9 | ||||
| 18:05 UTC | 210° 5 kt | 1013.9 | ||||
| 18:10 UTC | 220° 5 kt | 1013.9 | ||||
| 18:12 UTC | 84 | 67 | 220° 5 kt | 1013.9 | ||
| 18:15 UTC | 220° 9 kt | 1013.9 | ||||
| 18:20 UTC | 220° 10 kt | 1014.2 | ||||
| 18:25 UTC | 220° 10 kt | 1013.9 | ||||
| 18:27 UTC | 82 | 65 | 210° 10 kt | 1013.9 | VCTS | |
| 18:30 UTC | 170° 5 kt | 1013.9 | -RA | |||
| 18:35 UTC | 230° 4 kt | 1013.5 | -RA | |||
| 18:40 UTC | 210° 7 kt | 1013.5 | -RA | |||
| 18:42 UTC | 81 | 67 | 200° 7 kt | 1013.5 | -RA | |
| 18:45 UTC | 200° 8 kt | 1013.5 | -RA | |||
| 18:50 UTC | 210° 5 kt | 1013.5 | ||||
| 18:54 UTC | 82 | 65 | 200° 7 kt | 1013.2 | ||
| 18:55 UTC | 200° 7 kt | 1013.2 | ||||
| 19:00 UTC | 190° 5 kt | 1013.2 | ||||
| 19:05 UTC | 180° 5 kt | 1012.9 | ||||
| 19:08 UTC | 84 | 62 | 200° 6 kt | 1012.9 | VCTS | |
| 19:10 UTC | 180° 5 kt | 1012.9 | ||||
| 19:15 UTC | 180° 9 kt | 1012.9 | ||||
| 19:20 UTC | 170° 8 kt | 1012.9 | ||||
| 19:21 UTC | 85 | 66 | 190° 7 kt | 1012.9 | TS | |
| 19:25 UTC | 190° 7 kt | 1012.9 | ||||
| 19:30 UTC | 210° 7 kt | 1012.9 | ||||
| 19:35 UTC | 200° 7 kt | 1012.9 | ||||
| 19:40 UTC | 220° 9 kt | 1012.9 | ||||
| 19:45 UTC | 200° 8 kt | 1013.2 | ||||
| 19:50 UTC | 220° 7 kt | 1013.5 | ||||
| 19:54 UTC | 86 | 65 | 240° 7 kt | 1013.2 | VCTS | |
| 19:55 UTC | 220° 7 kt | 1013.2 | ||||
| 20:00 UTC | 220° 5 kt | 1013.2 | ||||
| 20:05 UTC | 0° 0 kt | 1012.9 | ||||
| 20:09 UTC | 85 | 66 | 4 kt | 1012.9 | ||
| 20:10 UTC | 20° 2 kt | 1012.9 | ||||
| 20:15 UTC | 50° 5 kt | 1012.9 | ||||
| 20:20 UTC | 30° 4 kt | 1012.9 | ||||
| 20:25 UTC | 40° 8 kt | 1012.9 | ||||
| 20:30 UTC | 30° 5 kt | 1012.9 | ||||
| 20:35 UTC | 170° 5 kt | 1012.5 | ||||
| 20:40 UTC | 170° 5 kt | 1012.5 | ||||
| 20:45 UTC | 180° 2 kt | 1012.2 | ||||
| 20:45 UTC | 84 | 63 | 180° 3 kt | 1012.2 | VCTS | |
| 20:50 UTC | 210° 10 kt | 1012.9 | ||||
| 20:54 UTC | 85 | 59 | 220° 8 kt | 1013.2 | VCTS | |
| 20:55 UTC | 230° 8 kt | 1013.2 | ||||
| 21:00 UTC | 31 | 1013.9 | ||||
| 21:05 UTC | 23 | 1013.5 | ||||
| 21:09 UTC | 72 | 58 | 330° 14 kt | 31 | 1013.9 | TS |
| 21:10 UTC | 320° 13 kt | 1013.9 | ||||
| 21:15 UTC | 320° 9 kt | 1013.9 | -RA | |||
| 21:18 UTC | 69 | 59 | 310° 7 kt | 20 | 1014.2 | VCTS -RA |
| 21:20 UTC | 310° 8 kt | 1014.6 | -RA | |||
| 21:25 UTC | 310° 9 kt | 1014.6 | -RA | |||
| 21:30 UTC | 330° 10 kt | 1014.2 | -RA | |||
| 21:35 UTC | 320° 7 kt | 1014.2 | -RA |
From the Iowa Environmental Mesonet's archive of airport observations.
The radar
The Minot AFB radar (KMBX), 48 km away, was scanning. The volume nearest the touchdown began at 19:39 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 |
|---|---|---|---|---|
| 19:38 UTC | TORNADO | 4 Sse Voltaire | Mchenry, ND | Short lived landspout tornado. |
| 19:54 UTC | TORNADO | 7 Nnw Ruso | Mchenry, ND | Short lived landspout tornado. |
| 21:30 UTC | TSTM WND GST 60 | 2 Nne Granville | Mchenry, ND | Winds lasted about 15 minutes. |
From the Iowa Environmental Mesonet's archive of National Weather Service local storm reports.
This ground now
The live radar over the trackEvery 2023 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 24, 2023
21 more were confirmed in the United States that day.
| Date | Time | Rating | Where | Path (mi) | Width (yd) | Deaths | Injuries | Damage |
|---|---|---|---|---|---|---|---|---|
| August 24 | 2:54 PM CDT | Unrated | McHenry, ND | 0.6 | 50 | |||
| August 24 | 4:55 PM EDT | EF0 | Collier, FL | 0.8 | 50 | $100,000 | ||
| August 24 | 8:15 PM EDT | EF1 | Kent, MI | 8.7 | 100 | $10 million | ||
| August 24 | 9:29 PM EDT | EF2 | Ingham, MI | 12.0 | 500 | 2 | 4 | $75 million |
| August 24 | 10:19 PM EDT | EF0 | Wayne, MI | 1.7 | 200 | $100,000 | ||
| August 24 | 10:23 PM EDT | EF1 | Wayne, MI | 3.0 | 200 | $60,000 | ||
| August 24 | 10:38 PM EDT | EF1 | Monroe, MI | 4.9 | 200 | $1.0 million | ||
| August 24 | 10:39 PM EDT | EF1 | Monroe, MI | 5.4 | 200 | $350,000 | ||
| August 24 | 10:43 PM EDT | EF1 | Wayne, MI | 1.4 | 300 | $50,000 | ||
| August 24 | 11:08 PM EDT | EF1 | Sandusky, OH | 4.5 | 100 | $35,000 | ||
| August 24 | 11:46 PM EDT | EF1 | Erie, OH | 0.3 | 100 | $30,000 | ||
| August 24 | 11:59 PM EDT | EF1 | Cuyahoga, OH | 0.8 | 150 | $165,000 | ||
| August 24 | 12:00 AM EDT | EF0 | Lorain, OH | 0.3 | 50 | $50,000 | ||
| August 24 | 12:05 AM EDT | EF0 | Lorain, OH | 1.1 | 100 | $40,000 | ||
| August 24 | 12:06 AM EDT | EF1 | Lake, OH | 3.3 | 150 | $200,000 | ||
| August 24 | 12:07 AM EDT | EF2 | Cuyahoga, OH | 1.5 | 100 | $300,000 | ||
| August 24 | 12:11 AM EDT | EF1 | Medina, OH | 1.5 | 200 | $20,000 | ||
| August 24 | 12:16 AM EDT | EF1 | Geauga, OH | 1.8 | 100 | $85,000 | ||
| August 24 | 12:18 AM EDT | EF1 | Geauga, OH | 1.2 | 175 | $50,000 | ||
| August 24 | 12:22 AM EDT | EF2 | Geauga, OH | 0.7 | 100 | $65,000 | ||
| August 24 | 12:35 AM EDT | EF0 | Trumbull, OH | 1.9 | 100 | $35,000 |
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.