Tornadoes · United States · Oklahoma · 1966

F1 tornado, Delaware County, Oklahoma, May 11, 1966

This F1 tornado ran 1.0 miles across Delaware County on May 11, 1966, touching down at 8:30 PM GMT-5 and reaching 1,200 yards wide. It killed nobody, and did $500 to $5,000 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 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 11, 1966
Touchdown
8:30 PM GMT-5 (01:30 UTC)
Path length
1.0 miles (1.6 km)
Path width
1,200 yards (1097 m)
Deaths
0
Injuries
0
Property damage
$500 to $5,000
County
Delaware County
Touchdown point
36.600, -94.800
Record number
145

This ground now

The live radar over the trackEvery 1966 tornado in OklahomaEvery tornado in Oklahoma since 1950Warnings in force in Oklahoma nowThe forecast where you are

The other tornadoes of May 11, 1966

14 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
May 112:45 PM GMT-5F0Pottawatomie, KS0.110
May 112:45 PM GMT-5F3Washington, KS5.4100$50,000 to $500,000
May 113:15 PM GMT-5F1Marshall, KS15.010
May 113:15 PM GMT-5F3Shawnee, KS9.9660$5,000 to $50,000
May 114:15 PM GMT-5F1Greenwood, KS0.110$500 to $5,000
May 114:30 PM GMT-5F0Greenwood, KS0.110
May 116:00 PM GMT-5F1Labette, KS0.110$5,000 to $50,000
May 117:00 PM GMT-5F1Ray, MO0.210$50 to $500
May 117:15 PM GMT-5F0Barton, MO0.110under $50
May 117:30 PM GMT-5F2Tulsa, OK2.01001$5,000 to $50,000
May 117:45 PM GMT-5F2Barton, MO2.350$5,000 to $50,000
May 118:30 PM GMT-5F2Rogers, OK8.4502$50,000 to $500,000
May 1110:10 PM GMT-5F0Phelps, MO0.110under $50
May 1110:42 PM GMT-5F1Miller, MO1.050$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.