Tornadoes · United States · North Dakota · 2019
EF0 tornado, Calio, North Dakota, July 8, 2019
This EF0 tornado ran 3.1 miles across Cavalier County on July 8, 2019, touching down at 4:32 PM CDT and reaching 200 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
- July 8, 2019
- Touchdown
- 4:32 PM CDT (21:32 UTC)
- Lifted
- 4:35 PM CDT (21:35 UTC)
- On the ground
- 3 minutes
- Path length
- 3.1 miles (4.9 km)
- Path width
- 200 yards (183 m)
- Deaths
- 0
- Injuries
- 0
- County
- Cavalier County
- Touchdown point
- 48.550, -98.940
- Lift-off point
- 48.577, -98.886
- Record number
- 1907081532-01
What the Weather Service recorded
By mid afternoon of July 8th, temperatures across eastern North Dakota and the northwest quarter of Minnesota had risen into the mid to upper 80s with dew points in the mid 60s to low 70s. A stationary boundary set up from west of Bismarck to near Rolla, North Dakota. Thunderstorms initially fired along this boundary, but as the evening wore on, the storms merged into lines, which tracked to the east-southeast. These storms mainly produced strong winds, but heavy rain was also reported in many areas. The Fargo-Moorhead area picked up quite a bit of rain in a short period of time, which resulted in flash flooding.
This tornado was likely wrapped in downburst winds and hail across portions of southwest Seivert Township, causing crop and tree damage. Peak winds were estimated at 85 mph.
From NOAA NCEI's Storm Events Database, the narrative the local forecast office wrote for Storm Data.
The warnings
10 minutes of warning. NWS FGF issued a tornado warning for this county at 21:22 UTC, 10 minutes before the tornado touched down, in force until 22:00 UTC.
The county was under a severe thunderstorm watch, issued at 18:43 UTC and running to 00:43 UTC.
| Issued (UTC) | Expired | Product | Office |
|---|---|---|---|
| 18:43 UTC | 00:43 UTC | Severe Thunderstorm Watch | FGF |
| 19:41 UTC | 20:15 UTC | Severe Thunderstorm Warning | FGF |
| 19:53 UTC | 00:29 UTC | Flash Flood Watch | FGF |
| 20:22 UTC | 21:15 UTC | Severe Thunderstorm Warning | FGF |
| 21:11 UTC | 22:00 UTC | Severe Thunderstorm Warning | FGF |
| 21:22 UTC | 22:00 UTC | Tornado Warning | FGF |
| 22:02 UTC | 03:00 UTC | Flood Advisory | FGF |
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 0.05 chance of a tornado within 25 miles. The outlook in force was issued at 19:56 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
9.5 hours before the tornado, 240 km from the path. July 8, 2019.
- Mixed-layer CAPE
- 1630 J/kg
- Mixed-layer CIN
- -203 J/kg
- Surface CAPE
- 902 J/kg
- Mixed-layer LCL
- 1099 m above ground
- 0-6 km bulk shear
- 24 kt
- 0-1 km bulk shear
- 15 kt
- 0-1 km storm-relative helicity
- 115 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
- 4.3 K/km
Bismarck Municip, ND (KBIS), 00:00Z
2.5 hours after it, 240 km from the path. July 9, 2019.
- Mixed-layer CAPE
- 1 J/kg
- Mixed-layer CIN
- -584 J/kg
- Surface CAPE
- 228 J/kg
- Mixed-layer LCL
- 1479 m above ground
- 0-6 km bulk shear
- 39 kt
- 0-1 km bulk shear
- 10 kt
- 0-1 km storm-relative helicity
- 17 m²/s²
- 0-3 km storm-relative helicity
- 65 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
- 0-3 km lapse rate
- 4.1 K/km
The radar
The Minot AFB radar (KMBX), 145 km away, was scanning. The volume nearest the touchdown began at 21:32 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 |
|---|---|---|---|---|
| 20:10 UTC | HAIL 1 | 11 Ene Rocklake | Towner, ND | LARGE HAIL AND STRONG WINDS DAMAGED CROPS IN EAST CENTRAL LANSING TOWNSHIP. TIME ESTIMATED BASED ON RADAR. |
| 21:06 UTC | TORNADO 0 | 4 S Newville | Towner, ND | TRAINED SPOTTER LOCATED NORTH OF STARKWEATHER REPORTED BRIEF TORNADO TOUCHDOWN ROUGHLY 4 TO 5 MILES TO THEIR WEST NORTHWEST. THIS TORNADO LIKELY TRACKED FOR ONE QUARTER MILE OR LESS AND LIFTED BY 407 PM CDT. PEAK WINDS E |
| 21:06 UTC | TORNADO | 4 S Newville | Towner, ND | TRAINED SPOTTER LOCATED NORTH OF STARKWEATHER REPORTED BRIEF TORNADO TOUCHDOWN ROUGHLY 4 TO 5 MILES TO THEIR WEST NORTHWEST. |
| 21:06 UTC | TORNADO | 5 Wnw Starkweather | Towner, ND | TRAINED SPOTTER REPORTED BRIEF TORNADO TOUCHDOWN. |
| 21:32 UTC | TORNADO 0 | 5 S Calio | Cavalier, ND | A TORNADO WAS LIKELY WRAPPED IN DOWNBURST WINDS AND HAIL ACROSS A PORTIONS OF SOUTHWEST SEIVERT TOWNSHIP. MORE EXTREME CROP AND TREE DAMAGE INDICATED THE TORNADO TRACKED FOR ABOUT A MILES TO AROUND 4 SSE OF CALIO BY 4 35 |
| 21:35 UTC | TSTM WND DMG | 5 S Calio | Cavalier, ND | CROPS WERE LAID FLAT OVER ACROSS SOUTHERN SEIVERT TOWNSHIP A MUTIPLE ROUNDS OF LARGE HAIL, STRONG WINDS AND HEAVY RAINS BETWEEN 430 AND 5 PM CDT. |
| 21:55 UTC | TSTM WND GST 54 | Langdon | Cavalier, ND | REPORT FROM LANGDON AWOS AT THE LANGDON AIRPORT. |
| 22:01 UTC | TSTM WND GST 63 | 1 E Langdon | Cavalier, ND | NDAWN SENSOR - 10 M WIND. |
| 23:00 UTC | TSTM WND DMG | 3 Sse Southam | Ramsey, ND | A FEW LARGE BRANCHES BROKEN DOWN IN A SHELTER BELT. |
From the Iowa Environmental Mesonet's archive of National Weather Service local storm reports.
This ground now
The live radar over the trackEvery 2019 tornado in North DakotaEvery tornado in North Dakota since 1950Warnings in force in North Dakota nowThe forecast where you are
The other tornadoes of July 8, 2019
4 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.