Tornadoes · United States · Minnesota · 2010
EF0 tornado, Currant Lake, Minnesota, July 17, 2010
This EF0 tornado ran 0.5 miles across Murray County on July 17, 2010, touching down at 8:22 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 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 17, 2010
- Touchdown
- 8:22 PM CDT (01:22 UTC)
- Lifted
- 8:23 PM CDT (01:23 UTC)
- On the ground
- 1 minutes
- Path length
- 0.5 miles (0.8 km)
- Path width
- 50 yards (46 m)
- Deaths
- 0
- Injuries
- 0
- County
- Murray County
- Touchdown point
- 44.070, -96.000
- Lift-off point
- 44.070, -95.990
- Record number
- 1007171922-01
What the Weather Service recorded
Thunderstorms produced damaging thunderstorm winds, along with a brief tornado, in Murray, Nobles, and Jackson Counties of southwest Minnesota on the evening of July 17th.
A brief tornado caused no reported damage.
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.
The county was under a tornado watch, issued at 21:38 UTC and running to 01:57 UTC.
| Issued (UTC) | Expired | Product | Office |
|---|---|---|---|
| 21:38 UTC | 01:57 UTC | Tornado Watch | FSD |
| 01:27 UTC | 04:30 UTC | Flash Flood Warning | FSD |
| 01:57 UTC | 03:19 UTC | Severe Thunderstorm Watch | FSD |
| 02:00 UTC | 02:45 UTC | Severe Thunderstorm Warning | FSD |
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 Moderate Risk, with a 0.05 chance of a tornado within 25 miles. The outlook in force was issued at 00:54 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.
Minneapolis, MN (KMPX), 00:00Z
1.4 hours before the tornado, 209 km from the path. July 18, 2010.
- Mixed-layer CAPE
- 1779 J/kg
- Mixed-layer CIN
- -139 J/kg
- Surface CAPE
- 2286 J/kg
- Mixed-layer LCL
- 1367 m above ground
- 0-6 km bulk shear
- 51 kt
- 0-1 km bulk shear
- 28 kt
- 0-1 km storm-relative helicity
- 268 m²/s²
- 0-3 km storm-relative helicity
- 618 m²/s²
- Significant tornado parameter
- 1.1
- Supercell composite
- 4.3
- 0-3 km lapse rate
- 5.3 K/km
Minneapolis, MN (KMPX), 12:00Z
10.6 hours after it, 209 km from the path. July 18, 2010.
- Mixed-layer CAPE
- 256 J/kg
- Mixed-layer CIN
- -150 J/kg
- Surface CAPE
- 0 J/kg
- Mixed-layer LCL
- 642 m above ground
- 0-6 km bulk shear
- 34 kt
- 0-1 km bulk shear
- 10 kt
- 0-1 km storm-relative helicity
- -11 m²/s²
- 0-3 km storm-relative helicity
- 55 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- -0.2
- 0-3 km lapse rate
- 4.4 K/km
The surface observations
Slayton (DVP), 19 km from the path, in the two hours either side.
| Time (UTC) | Temp (°F) | Dew point (°F) | Wind | Gust (kt) | Pressure (mb) | Weather |
|---|---|---|---|---|---|---|
| 23:36 UTC | 86.18 | 67.64 | 170° 10 kt | 1009.1 | ||
| 23:57 UTC | 85 | 68.36 | 160° 9 kt | 1009.1 | ||
| 00:16 UTC | 84.2 | 69.44 | 160° 7 kt | 1008.8 | ||
| 00:36 UTC | 83.3 | 71 | 150° 6 kt | 1008.5 | ||
| 00:56 UTC | 82.76 | 72.5 | 90° 7 kt | 1008.8 | VCTS | |
| 01:17 UTC | 83.3 | 71.24 | 60° 13 kt | 1011.9 | VCTS | |
| 01:36 UTC | 83.3 | 71.78 | 110° 10 kt | 18 | 1010.2 | -TSRA |
| 02:15 UTC | 67.28 | 64.4 | 350° 15 kt | 1015.2 | TS | |
| 02:16 UTC | 67.28 | 64.58 | 360° 14 kt | 1015.2 | TS | |
| 02:36 UTC | 70.7 | 66 | 210° 18 kt | 29 | 1011.2 | +TSRA |
| 02:56 UTC | 69.8 | 61.7 | 200° 9 kt | 1010.5 | VCTS | |
| 03:16 UTC | 68 | 64.22 | 120° 11 kt | 1010.2 | TS |
From the Iowa Environmental Mesonet's archive of airport observations.
The radar
The Sioux Falls radar (KFSD), 80 km away, was scanning. The volume nearest the touchdown began at 01:21 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 |
|---|---|---|---|---|
| 01:22 UTC | TORNADO | 5 Nnw Lake Wilson | Murray, MN | TORNADO TOUCHED DOWN FOR 1 TO 2 MINUTES AND LIFTED |
| 02:05 UTC | TSTM WND GST 60 | 1 Wnw Currie | Murray, MN | HEAVY RAIN AND WINDS ESTIMATED AT 60 MPH. |
| 02:07 UTC | TSTM WND DMG | 8 Nne Slayton | Murray, MN | TREES DOWN IN LAKE SHETEK STATE PARK |
| 02:26 UTC | TSTM WND GST 70 | Lismore | Nobles, MN | 60 TO 70 MPH WINDS LASTED 2 TO 3 MINUTES. |
From the Iowa Environmental Mesonet's archive of National Weather Service local storm reports.
This ground now
The live radar over the trackEvery 2010 tornado in MinnesotaEvery tornado in Minnesota since 1950Warnings in force in Minnesota nowThe forecast where you are
The other tornadoes of July 17, 2010
6 more were confirmed in the United States that day.
| Date | Time | Rating | Where | Path (mi) | Width (yd) | Deaths | Injuries | Damage |
|---|---|---|---|---|---|---|---|---|
| July 17 | 5:12 PM CDT | EF0 | Wadena, MN | 0.4 | 15 | |||
| July 17 | 6:50 PM CDT | EF0 | Morrison, MN | 1.4 | 30 | $250,000 | ||
| July 17 | 7:30 PM CDT | EF0 | Stearns, MN | 0.1 | 30 | $50,000 | ||
| July 17 | 7:48 PM CDT | EF0 | Wright, MN | 4.2 | 50 | $100,000 | ||
| July 17 | 8:23 PM CDT | EF0 | Lincoln, NE | 0.1 | 5 | |||
| July 17 | 8:44 PM CDT | EF0 | Washington, MN | 5.2 | 50 | $50,000 |
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.