Tornadoes · United States · Texas · 1958

F1 tornado, Williamson County, Texas, May 2, 1958

This F1 tornado ran 11.5 miles across Williamson County on May 2, 1958, touching down at 4:50 PM GMT-5 and reaching 440 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 mph

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

  2. F173 to 112 mphthis tornado

    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
F1
Date
May 2, 1958
Touchdown
4:50 PM GMT-5 (21:50 UTC)
Path length
11.5 miles (18.5 km)
Path width
440 yards (402 m)
Deaths
0
Injuries
0
Property damage
under $50
County
Williamson County
Touchdown point
30.600, -97.400
Lift-off point
30.680, -97.570
Record number
126

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.

San Antonio Intl, TX (KSAT), 12:00Z

9.8 hours before the tornado, 152 km from the path. May 2, 1958.

Skew-T log-pSkew-T log-p diagram, San Antonio Intl, TX at 12:00Z on 1958-05-02Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 558 joules per kilogram, CIN -67, lifted condensation level 638 meters above ground. Wind barbs in knots down the right edge.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 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, San Antonio Intl, TX at 12:00Z on 1958-05-02The 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 121 square meters per square second, 0 to 6 km bulk shear 43 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
558 J/kg
Mixed-layer CIN
-67 J/kg
Surface CAPE
1435 J/kg
Mixed-layer LCL
638 m above ground
0-6 km bulk shear
43 kt
0-1 km bulk shear
23 kt
0-1 km storm-relative helicity
121 m²/s²
0-3 km storm-relative helicity
172 m²/s²
Significant tornado parameter
0.3
Supercell composite
4.1
0-3 km lapse rate
5.6 K/km

Open this sounding in Storm Lab

San Antonio Intl, TX (KSAT), 00:00Z

2.2 hours after it, 152 km from the path. May 3, 1958.

Skew-T log-pSkew-T log-p diagram, San Antonio Intl, TX at 00:00Z on 1958-05-03Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 881 joules per kilogram, CIN -122, lifted condensation level 1109 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, San Antonio Intl, TX at 00:00Z on 1958-05-03The 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 388 square meters per square second, 0 to 6 km bulk shear 65 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
881 J/kg
Mixed-layer CIN
-122 J/kg
Surface CAPE
363 J/kg
Mixed-layer LCL
1109 m above ground
0-6 km bulk shear
65 kt
0-1 km bulk shear
35 kt
0-1 km storm-relative helicity
388 m²/s²
0-3 km storm-relative helicity
491 m²/s²
Significant tornado parameter
0.0
Supercell composite
8.7
0-3 km lapse rate
4.0 K/km

Open this sounding in Storm Lab

The surface observations

Austin - City/Camp Mabry (ATT), 44 km from the path, in the two hours either side.

Time (UTC)Temp (°F)Dew point (°F)WindGust (kt)Pressure (mb)Weather
20:00 UTC71700° 0 kt1011.5-TSRA
21:00 UTC71690° 0 kt1011.2-TSRA
22:00 UTC6762250° 10 kt1013.2-TSRA
23:00 UTC676540° 8 kt1011.9-TSRA

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

This ground now

The live radar over the trackEvery 1958 tornado in TexasEvery tornado in Texas since 1950Warnings in force in Texas nowThe forecast where you are

The other tornadoes of May 2, 1958

4 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
May 211:25 AM GMT-5F2Medina, TX20.8200$50,000 to $500,000
May 24:20 PM GMT-5F2LeFlore, OK0.3100$5,000 to $50,000
May 24:20 PM GMT-5F1Hays, TX7.4440under $50
May 212:15 AM GMT-5F1McCracken, KY0.110$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.