Tornadoes · United States · Texas · 1968

F0 tornado, Gray and Carson counties, Texas, July 17, 1968

This F0 tornado ran 3.8 miles across Gray and Carson counties on July 17, 1968, touching down at 9:02 PM GMT-5 and reaching 33 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
July 17, 1968
Touchdown
9:02 PM GMT-5 (02:02 UTC)
Path length
3.8 miles (6.1 km)
Path width
33 yards (30 m)
Deaths
0
Injuries
0
Counties
Gray and Carson counties
Touchdown point
35.520, -101.030
Lift-off point
35.570, -101.000
Record number
456

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.

Amarillo Airport, TX (KAMA), 00:00Z

2.0 hours before the tornado, 71 km from the path. July 18, 1968.

Skew-T log-pSkew-T log-p diagram, Amarillo Airport, TX at 00:00Z on 1968-07-18Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 364 joules per kilogram, CIN -107, lifted condensation level 2786 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, Amarillo Airport, TX at 00:00Z on 1968-07-18The 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 -6 square meters per square second, 0 to 6 km bulk shear 10 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
364 J/kg
Mixed-layer CIN
-107 J/kg
Surface CAPE
876 J/kg
Mixed-layer LCL
2786 m above ground
0-6 km bulk shear
10 kt
0-1 km bulk shear
3 kt
0-1 km storm-relative helicity
-6 m²/s²
0-3 km storm-relative helicity
27 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0
0-3 km lapse rate
8.3 K/km

Open this sounding in Storm Lab

Amarillo Airport, TX (KAMA), 12:00Z

10.0 hours after it, 71 km from the path. July 18, 1968.

Skew-T log-pSkew-T log-p diagram, Amarillo Airport, TX at 12:00Z on 1968-07-18Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 138 joules per kilogram, CIN -258, lifted condensation level 1839 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, Amarillo Airport, TX at 12:00Z on 1968-07-18The 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 -43 square meters per square second, 0 to 6 km bulk shear 25 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
138 J/kg
Mixed-layer CIN
-258 J/kg
Surface CAPE
137 J/kg
Mixed-layer LCL
1839 m above ground
0-6 km bulk shear
25 kt
0-1 km bulk shear
20 kt
0-1 km storm-relative helicity
-43 m²/s²
0-3 km storm-relative helicity
-14 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.5
0-3 km lapse rate
4.9 K/km

Open this sounding in Storm Lab

The surface observations

Amarillo - Rick Husband Intl (AMA), 72 km from the path, in the two hours either side.

Time (UTC)Temp (°F)Dew point (°F)WindGust (kt)Pressure (mb)Weather
01:00 UTC9261340° 12 kt1007.8
02:00 UTC8062300° 25 kt1010.5-TSRA
03:00 UTC7359330° 9 kt1010.5-TSRA
04:00 UTC7955360° 8 kt1010.2

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

This ground now

The live radar over the trackEvery 1968 tornado in TexasEvery tornado in Texas since 1950Warnings in force in Texas nowThe forecast where you are

The other tornadoes of July 17, 1968

10 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
July 171:47 PM GMT-5F0Stearns, MN0.110
July 173:55 PM GMT-4F2Hillsborough, NH0.117$5,000 to $50,000
July 176:30 PM GMT-4F1Worcester, MA0.317$500 to $5,000
July 176:30 PM GMT-5F0Carson, TX0.5100
July 176:55 PM GMT-5F0Callaway, MO0.550$500 to $5,000
July 177:15 PM GMT-5F1Comanche, KS0.5300
July 177:15 PM GMT-5F1Comanche, KS0.110
July 177:30 PM GMT-5F1Warren, IL3.8127$50 to $500
July 179:02 PM GMT-5F0Carson, TX4.533
July 179:35 PM GMT-5F0Wheeler, TX0.110

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.