Tornadoes · United States · Texas · 1991

F0 tornado, McCulloch County, Texas, May 3, 1991

This F0 tornado ran 0.2 miles across McCulloch County on May 3, 1991, touching down at 2:49 PM CDT and reaching 10 yards wide. It killed nobody.

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 3, 1991
Touchdown
2:49 PM CDT (19:49 UTC)
Path length
0.2 miles (0.3 km)
Path width
10 yards (9 m)
Deaths
0
Injuries
0
County
McCulloch County
Touchdown point
31.430, -99.600
Record number
427

The warnings

2 minutes of warning. NWS SJT issued a tornado warning for this county at 19:47 UTC, 2 minutes before the tornado touched down, in force until 20:45 UTC.

Issued (UTC)ExpiredProductOffice
19:38 UTC20:45 UTCSevere Thunderstorm WarningSJT
19:47 UTC20:45 UTCTornado WarningSJT
20:45 UTC21:45 UTCSevere Thunderstorm WarningSJT
21:37 UTC22:30 UTCTornado WarningSJT

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 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.

Stephenville/Cla, TX (KSEP), 12:00Z

7.8 hours before the tornado, 167 km from the path. May 3, 1991.

Skew-T log-pSkew-T log-p diagram, Stephenville/Cla, TX at 12:00Z on 1991-05-03Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 2305 joules per kilogram, CIN -106, lifted condensation level 718 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, Stephenville/Cla, TX at 12:00Z on 1991-05-03The 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 257 square meters per square second, 0 to 6 km bulk shear 48 knots.1939587897117Sfc1 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
2305 J/kg
Mixed-layer CIN
-106 J/kg
Surface CAPE
1383 J/kg
Mixed-layer LCL
718 m above ground
0-6 km bulk shear
48 kt
0-1 km bulk shear
28 kt
0-1 km storm-relative helicity
257 m²/s²
0-3 km storm-relative helicity
236 m²/s²
Significant tornado parameter
1.9
Supercell composite
13.9
0-3 km lapse rate
4.7 K/km

Open this sounding in Storm Lab

Stephenville/Cla, TX (KSEP), 00:00Z

4.2 hours after it, 167 km from the path. May 4, 1991.

Skew-T log-pSkew-T log-p diagram, Stephenville/Cla, TX at 00:00Z on 1991-05-04Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 79 joules per kilogram, CIN -233, lifted condensation level 1234 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, Stephenville/Cla, TX at 00:00Z on 1991-05-04The 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 90 square meters per square second, 0 to 6 km bulk shear 43 knots.1939587897Sfc1 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
79 J/kg
Mixed-layer CIN
-233 J/kg
Surface CAPE
317 J/kg
Mixed-layer LCL
1234 m above ground
0-6 km bulk shear
43 kt
0-1 km bulk shear
9 kt
0-1 km storm-relative helicity
90 m²/s²
0-3 km storm-relative helicity
87 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.1
0-3 km lapse rate
5.2 K/km

Open this sounding in Storm Lab

This ground now

The live radar over the trackEvery 1991 tornado in TexasEvery tornado in Texas since 1950Warnings in force in Texas nowThe forecast where you are

The other tornadoes of May 3, 1991

3 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
May 31:15 PM CDTF0Runnels, TX0.770
May 36:30 PM CDTF1Houston, TX0.210
May 39:10 PM CDTF1San Augustine, TX0.210$500 to $5,000

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.