Tornadoes · United States · Oklahoma · 2010

EF0 tornado, Lone Grove, Oklahoma, September 8, 2010

This EF0 tornado ran 0.1 miles across Carter County on September 8, 2010, touching down at 7:00 PM CDT and reaching 25 yards wide. It killed nobody, and did $20,000 of property damage.

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
September 8, 2010
Touchdown
7:00 PM CDT (00:00 UTC)
Path length
0.1 miles (0.2 km)
Path width
25 yards (23 m)
Deaths
0
Injuries
0
Property damage
$20,000
County
Carter County
Touchdown point
34.221, -97.309
Lift-off point
34.221, -97.309
Record number
1009081800-01

What the Weather Service recorded

The remnants of Tropical Storm Hermine moved north into southern and central Oklahoma, bringing with it heavy rain and three tornadoes. The most significant impact with this storm came from three tornadoes. The most significant tornado occurred near Colbert in Bryan County. Two homes sustained moderate damage and two trucks were overturned. One of the drivers sustained minor injuries while in the truck.

Photographic evidence and radar data suggests a tornado developed between Prairie Valley and Rolling Hills Roads. Two homes sustained minor 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 22:39 UTC and running to 06:00 UTC.

Issued (UTC)ExpiredProductOffice
22:39 UTC06:00 UTCTornado WatchOUN

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 Slight Risk, with a 0.05 chance of a tornado within 25 miles. The outlook in force was issued at 21:55 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.

Norman, OK (KOUN), 00:00Z

0.0 hours before the tornado, 111 km from the path. September 9, 2010.

Skew-T log-pSkew-T log-p diagram, Norman, OK at 00:00Z on 2010-09-09Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 32 joules per kilogram, CIN -23, lifted condensation level 463 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, Norman, OK at 00:00Z on 2010-09-09The 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 463 square meters per square second, 0 to 6 km bulk shear 27 knots.193958Sfc1 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
32 J/kg
Mixed-layer CIN
-23 J/kg
Surface CAPE
11 J/kg
Mixed-layer LCL
463 m above ground
0-6 km bulk shear
27 kt
0-1 km bulk shear
44 kt
0-1 km storm-relative helicity
463 m²/s²
0-3 km storm-relative helicity
640 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.4
0-3 km lapse rate
4.4 K/km

Open this sounding in Storm Lab

Norman, OK (KOUN), 12:00Z

12.0 hours after it, 111 km from the path. September 9, 2010.

Skew-T log-pSkew-T log-p diagram, Norman, OK at 12:00Z on 2010-09-09Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 5 joules per kilogram, CIN -325, lifted condensation level 472 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, Norman, OK at 12:00Z on 2010-09-09The 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 116 square meters per square second, 0 to 6 km bulk shear 11 knots.193958Sfc1 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
5 J/kg
Mixed-layer CIN
-325 J/kg
Surface CAPE
16 J/kg
Mixed-layer LCL
472 m above ground
0-6 km bulk shear
11 kt
0-1 km bulk shear
20 kt
0-1 km storm-relative helicity
116 m²/s²
0-3 km storm-relative helicity
152 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0
0-3 km lapse rate
3.4 K/km

Open this sounding in Storm Lab

The radar

The Norman radar (KTLX), 124 km away, was scanning. The volume nearest the touchdown began at 00:02 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)ReportWhereCountyRemark
00:00 UTCTORNADO4 Nw Lone GroveCarter, OKTHE TORNADO WAS REPORTED BETWEEN PRAIRIE VALLEY AND ROLLING HILLS ROADS, DAMAGING TWO HOMES. THE TIME AND LOCATION ARE APPROXIMATE.
01:15 UTCTORNADO6 S MariettaLove, OKBRIEF TOUCHDOWN WITH NO DAMAGE REPORTED.

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 OklahomaEvery tornado in Oklahoma since 1950Warnings in force in Oklahoma nowThe forecast where you are

The other tornadoes of September 8, 2010

9 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
September 84:18 AM CDTEF0Coryell, TX0.150
September 82:05 PM CDTEF1Bryan, OK0.1251
September 85:20 PM CDTEF0Lamar, TX1.9200$100,000
September 85:36 PM CDTEF1Ellis, TX9.9704$200,000
September 85:55 PM CDTEF0Falls, TX0.6115
September 86:10 PM CDTEF2Dallas, TX2.75161$750,000
September 86:20 PM CDTEF0Rockwall, TX0.7108$50,000
September 87:30 PM CDTEF0Cooke, TX0.050
September 88:15 PM CDTEF0Love, OK0.110

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.