Tornadoes · United States · Oklahoma · 1983

F0 tornado, Grant County, Oklahoma, May 12, 1983

This F0 tornado ran 0.1 miles across Grant County on May 12, 1983, touching down at 7:00 PM CDT and reaching 50 yards wide. It killed nobody, and did under $50 of property damage.

The rating scale

Tracks are drawn in the color of the rating. The Fujita scale rates the damage rather than measuring the wind: the speeds are what that damage is taken to imply.

  1. F040 to 72 mphthis tornado

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

  2. F173 to 112 mph

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

  3. F2113 to 157 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. F3158 to 206 mph

    Severe damage. Whole stories of well-built houses destroyed, large buildings badly damaged, trains overturned, trees debarked, heavy cars lifted and thrown.

  5. F4207 to 260 mph

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

  6. F5261 to 318 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
F0
Date
May 12, 1983
Touchdown
7:00 PM CDT (00:00 UTC)
Path length
0.1 miles (0.2 km)
Path width
50 yards (46 m)
Deaths
0
Injuries
0
Property damage
under $50
County
Grant County
Touchdown point
36.680, -97.550
Record number
261

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.

Ok Cty/Will Rgrs, OK (KOKC), 00:00Z

0.0 hours before the tornado, 142 km from the path. May 13, 1983.

Skew-T log-pSkew-T log-p diagram, Ok Cty/Will Rgrs, OK at 00:00Z on 1983-05-13Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 2518 joules per kilogram, CIN -6, lifted condensation level 1243 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, Ok Cty/Will Rgrs, OK at 00:00Z on 1983-05-13The 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 63 square meters per square second, 0 to 6 km bulk shear 28 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
2518 J/kg
Mixed-layer CIN
-6 J/kg
Surface CAPE
3076 J/kg
Mixed-layer LCL
1243 m above ground
0-6 km bulk shear
28 kt
0-1 km bulk shear
9 kt
0-1 km storm-relative helicity
63 m²/s²
0-3 km storm-relative helicity
101 m²/s²
Significant tornado parameter
0.6
Supercell composite
4.2
0-3 km lapse rate
7.0 K/km

Open this sounding in Storm Lab

Ok Cty/Will Rgrs, OK (KOKC), 12:00Z

12.0 hours after it, 142 km from the path. May 13, 1983.

Skew-T log-pSkew-T log-p diagram, Ok Cty/Will Rgrs, OK at 12:00Z on 1983-05-13Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 50 joules per kilogram, CIN -209, lifted condensation level 844 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, Ok Cty/Will Rgrs, OK at 12:00Z on 1983-05-13The 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 166 square meters per square second, 0 to 6 km bulk shear 33 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
50 J/kg
Mixed-layer CIN
-209 J/kg
Surface CAPE
7 J/kg
Mixed-layer LCL
844 m above ground
0-6 km bulk shear
33 kt
0-1 km bulk shear
19 kt
0-1 km storm-relative helicity
166 m²/s²
0-3 km storm-relative helicity
278 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0
0-3 km lapse rate
4.8 K/km

Open this sounding in Storm Lab

This ground now

The live radar over the trackEvery 1983 tornado in OklahomaEvery tornado in Oklahoma since 1950Warnings in force in Oklahoma nowThe forecast where you are

The other tornadoes of May 12, 1983

7 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
May 125:20 PM CDTF0Brown, KS2.550$5,000 to $50,000
May 126:37 PM CDTF0Kay, OK0.150under $50
May 127:05 PM CDTF0Kay, OK0.150under $50
May 127:20 PM CDTF0Cottle, TX0.550under $50
May 127:52 PM CDTF0Garfield, OK0.150under $50
May 129:15 PM CDTF2Greer, OK0.150$500 to $5,000
May 129:30 PM CDTF2Jackson, OK0.150under $50

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.