Tornadoes · United States · Texas · 1981

F0 tornado, Karnes County, Texas, August 30, 1981

This F0 tornado ran 0.3 miles across Karnes County on August 30, 1981, touching down at 6:30 PM CDT and reaching 37 yards wide. It killed nobody, and did $5,000 to $50,000 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
August 30, 1981
Touchdown
6:30 PM CDT (23:30 UTC)
Path length
0.3 miles (0.5 km)
Path width
37 yards (34 m)
Deaths
0
Injuries
0
Property damage
$5,000 to $50,000
County
Karnes County
Touchdown point
28.770, -97.800
Record number
711

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.

Victoria Regiona, TX (KVCT), 12:00Z

11.5 hours before the tornado, 88 km from the path. August 30, 1981.

Skew-T log-pSkew-T log-p diagram, Victoria Regiona, TX at 12:00Z on 1981-08-30Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 1647 joules per kilogram, CIN -3, lifted condensation level 546 meters above ground. Wind barbs in knots down the right edge.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 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, Victoria Regiona, TX at 12:00Z on 1981-08-30The 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 91 square meters per square second, 0 to 6 km bulk shear 26 knots.1939Sfc1 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
1647 J/kg
Mixed-layer CIN
-3 J/kg
Surface CAPE
1431 J/kg
Mixed-layer LCL
546 m above ground
0-6 km bulk shear
26 kt
0-1 km bulk shear
19 kt
0-1 km storm-relative helicity
91 m²/s²
0-3 km storm-relative helicity
99 m²/s²
Significant tornado parameter
0.6
Supercell composite
3.6
0-3 km lapse rate
4.9 K/km

Open this sounding in Storm Lab

Victoria Regiona, TX (KVCT), 00:00Z

0.5 hours after it, 88 km from the path. August 31, 1981.

Skew-T log-pSkew-T log-p diagram, Victoria Regiona, TX at 00:00Z on 1981-08-31Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 1415 joules per kilogram, CIN -3, lifted condensation level 546 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, Victoria Regiona, TX at 00:00Z on 1981-08-31The 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 132 square meters per square second, 0 to 6 km bulk shear 33 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
1415 J/kg
Mixed-layer CIN
-3 J/kg
Surface CAPE
1499 J/kg
Mixed-layer LCL
546 m above ground
0-6 km bulk shear
33 kt
0-1 km bulk shear
21 kt
0-1 km storm-relative helicity
132 m²/s²
0-3 km storm-relative helicity
189 m²/s²
Significant tornado parameter
0.8
Supercell composite
4.8
0-3 km lapse rate
5.4 K/km

Open this sounding in Storm Lab

The surface observations

Victoria Regional (VCT), 85 km from the path, in the two hours either side.

Time (UTC)Temp (°F)Dew point (°F)WindGust (kt)Pressure (mb)Weather
22:00 UTC7977100° 8 kt1009.5-RA
23:00 UTC7977100° 9 kt1009.5
00:00 UTC7977100° 10 kt1009.1
01:00 UTC787780° 8 kt1008.5

From the Iowa Environmental Mesonet's archive of airport observations.

This ground now

The live radar over the trackEvery 1981 tornado in TexasEvery tornado in Texas since 1950Warnings in force in Texas nowThe forecast where you are

The other tornadoes of August 30, 1981

5 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
August 303:45 PM CDTF1Live Oak, TX1.0402$50,000 to $500,000
August 304:15 PM CDTF0Atascosa, TX0.540
August 304:45 PM CDTF0Bexar, TX0.827
August 305:10 PM CDTF1Bee, TX0.843$50,000 to $500,000
August 306:50 PM CDTF0Goliad, TX0.227

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.