Tornadoes · United States · North Dakota · 2012

EF0 tornado, Noonan, North Dakota, July 21, 2012

This EF0 tornado ran 1.1 miles across Divide County on July 21, 2012, touching down at 10:10 PM CDT and reaching 30 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.

  1. EF065 to 85 mphthis tornado

    Light damage. Surface peeled off some roofs, gutters and siding damaged, branches broken, shallow-rooted trees pushed over.

  2. EF186 to 110 mph

    Moderate damage. Roofs badly stripped, mobile homes overturned or badly damaged, exterior doors lost, windows broken.

  3. 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.

  4. 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.

  5. EF4166 to 200 mph

    Devastating damage. Well-built houses leveled, structures with weak foundations moved some distance, cars thrown and large missiles generated.

  6. 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.

  7. 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 21, 2012
Touchdown
10:10 PM CDT (03:10 UTC)
Lifted
10:15 PM CDT (03:15 UTC)
On the ground
5 minutes
Path length
1.1 miles (1.8 km)
Path width
30 yards (27 m)
Deaths
0
Injuries
0
County
Divide County
Touchdown point
48.820, -103.010
Lift-off point
48.821, -102.985
Record number
1207212110-01

What the Weather Service recorded

Severe Thunderstorm Watch number 500 was in effect during this event.||A surface trough advancing into western North Dakota was the focus for convection during the evening hours. Severe thunderstorms developed along this boundary over northwest North Dakota near a weak mid level short wave trough advecting east across far southern Canada. Severe convection was supported by effective shear magnitudes up to 50 knots and moderate instability. Several severe weather reports were received, including one EF0 tornado which briefly touched down in rural Divide County.

This tornado briefly touched down in the open country of Divide County. There were no reports of damage associated with this tornado and it was rated EF0.

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 severe thunderstorm watch, issued at 22:41 UTC and running to 05:46 UTC.

Issued (UTC)ExpiredProductOffice
22:41 UTC05:46 UTCSevere Thunderstorm WatchBIS
01:42 UTC02:06 UTCSevere Thunderstorm WarningBIS
03:14 UTC04:15 UTCSevere Thunderstorm WarningBIS

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 00:56 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.

Glasgow Intl Airport, MT (KGGW), 00:00Z

3.2 hours before the tornado, 274 km from the path. July 22, 2012.

Skew-T log-pSkew-T log-p diagram, Glasgow Intl Airport, MT at 00:00Z on 2012-07-22Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 1989 joules per kilogram, CIN -23, lifted condensation level 1900 meters above ground. Wind barbs in knots down the right edge.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed. The warm shading is its CAPE, the cool shading the inhibition it has to break through.
HodographHodograph, Glasgow Intl Airport, MT at 00:00Z on 2012-07-22The wind through the lowest 10 kilometers as a curve, rings every 10 meters per second labeled in knots. Zero to 1 km storm-relative helicity 25 square meters per square second, 0 to 6 km bulk shear 39 knots.19395878Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km. RM and LM are the right and left moving storms Bunkers' method gives; the shaded area is the 0 to 1 km storm-relative helicity.
Mixed-layer CAPE
1989 J/kg
Mixed-layer CIN
-23 J/kg
Surface CAPE
2899 J/kg
Mixed-layer LCL
1900 m above ground
0-6 km bulk shear
39 kt
0-1 km bulk shear
7 kt
0-1 km storm-relative helicity
25 m²/s²
0-3 km storm-relative helicity
97 m²/s²
Significant tornado parameter
0.0
Supercell composite
2.8
0-3 km lapse rate
8.2 K/km

Open this sounding in Storm Lab

Glasgow Intl Airport, MT (KGGW), 12:00Z

8.8 hours after it, 274 km from the path. July 22, 2012.

Skew-T log-pSkew-T log-p diagram, Glasgow Intl Airport, MT at 12:00Z on 2012-07-22Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 0 joules per kilogram, CIN -73626, lifted condensation level 2097 meters above ground. Wind barbs in knots down the right edge.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed. The warm shading is its CAPE, the cool shading the inhibition it has to break through.
HodographHodograph, Glasgow Intl Airport, MT at 12:00Z on 2012-07-22The wind through the lowest 10 kilometers as a curve, rings every 10 meters per second labeled in knots. Zero to 1 km storm-relative helicity -30 square meters per square second, 0 to 6 km bulk shear 28 knots.19395878Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km. RM and LM are the right and left moving storms Bunkers' method gives; the shaded area is the 0 to 1 km storm-relative helicity.
Mixed-layer CAPE
0 J/kg
Mixed-layer CIN
-73626 J/kg
Surface CAPE
0 J/kg
Mixed-layer LCL
2097 m above ground
0-6 km bulk shear
28 kt
0-1 km bulk shear
13 kt
0-1 km storm-relative helicity
-30 m²/s²
0-3 km storm-relative helicity
75 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0
0-3 km lapse rate
3.6 K/km

Open this sounding in Storm Lab

The surface observations

Crosby (D50), 25 km from the path, in the two hours either side.

Time (UTC)Temp (°F)Dew point (°F)WindGust (kt)Pressure (mb)Weather
01:15 UTC82.464.4120° 7 kt1012.2
01:35 UTC78.864.4130° 8 kt1012.2
01:55 UTC7764.4140° 11 kt1011.9
02:15 UTC78.864.4170° 13 kt191010.8
02:35 UTC7764.4180° 11 kt1011.2
02:55 UTC75.266.2280° 9 kt161012.9
03:15 UTC6866.2330° 26 kt341014.6VCTS BR
03:35 UTC66.266.240° 8 kt151014.2VCTS RA

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)ReportWhereCountyRemark
01:30 UTCHAIL 1AlamoWilliams, NDREPORTED HEAVY RAINFALL.
03:10 UTCTORNADO5 S NoonanDivide, NDREPORTED SEEING A SMALL ROPE TORNADO TOUCH DOWN BRIEFLY TO THE NORTHWEST.
05:00 UTCTSTM WND GST 709 W NiobeBurke, NDPENNY SIZE HAIL AND VERY HEAVY RAIN ALSO.

From the Iowa Environmental Mesonet's archive of National Weather Service local storm reports.

This ground now

The live radar over the trackEvery 2012 tornado in North DakotaEvery tornado in North Dakota since 1950Warnings in force in North Dakota nowThe forecast where you are

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.