Tornadoes · United States · Oklahoma · 1991
F0 tornado, Garfield County, Oklahoma, April 26, 1991
This F0 tornado ran 0.1 miles across Garfield County on April 26, 1991, touching down at 6:15 PM CDT and reaching 20 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.
F040 to 72 mphthis tornado
Light damage. Surface peeled off some roofs, gutters and siding damaged, branches broken, shallow-rooted trees pushed over.
F173 to 112 mph
Moderate damage. Roofs badly stripped, mobile homes overturned or badly damaged, exterior doors lost, windows broken.
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.
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.
F4207 to 260 mph
Devastating damage. Well-built houses leveled, structures with weak foundations moved some distance, cars thrown and large missiles generated.
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.
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
- April 26, 1991
- Touchdown
- 6:15 PM CDT (23:15 UTC)
- Path length
- 0.1 miles (0.2 km)
- Path width
- 20 yards (18 m)
- Deaths
- 0
- Injuries
- 0
- County
- Garfield County
- Touchdown point
- 36.430, -97.600
- Record number
- 319
The warnings
19 minutes of warning. NWS OUN issued a tornado warning for this county at 22:56 UTC, 19 minutes before the tornado touched down, in force until 23:30 UTC.
| Issued (UTC) | Expired | Product | Office |
|---|---|---|---|
| 09:14 UTC | 10:15 UTC | Severe Thunderstorm Warning | OUN |
| 10:27 UTC | 11:15 UTC | Severe Thunderstorm Warning | OUN |
| 11:12 UTC | 12:00 UTC | Severe Thunderstorm Warning | OUN |
| 21:40 UTC | 22:45 UTC | Severe Thunderstorm Warning | OUN |
| 22:42 UTC | 23:30 UTC | Severe Thunderstorm Warning | OUN |
| 22:56 UTC | 23:30 UTC | Tornado Warning | OUN |
| 23:27 UTC | 23:45 UTC | Tornado Warning | OUN |
| 01:48 UTC | 02:45 UTC | Severe Thunderstorm Warning | OUN |
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 forecast that day
The Storm Prediction Center had this point in a High Risk. The outlook in force was issued at 06:35 UTC.
SPC's Day 1 convective outlook as it stood when the tornado began, read at the touchdown point. The same archive is on the radar archive.
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.
Norman, OK (KOUN), 12:00Z
11.3 hours before the tornado, 136 km from the path. April 26, 1991.
- Mixed-layer CAPE
- 2265 J/kg
- Mixed-layer CIN
- -6 J/kg
- Surface CAPE
- 2452 J/kg
- Mixed-layer LCL
- 595 m above ground
- 0-6 km bulk shear
- 39 kt
- 0-1 km bulk shear
- 33 kt
- 0-1 km storm-relative helicity
- 213 m²/s²
- 0-3 km storm-relative helicity
- 301 m²/s²
- Significant tornado parameter
- 2.3
- Supercell composite
- 12.2
- 0-3 km lapse rate
- 5.5 K/km
Norman, OK (KOUN), 00:00Z
0.7 hours after it, 136 km from the path. April 27, 1991.
- Mixed-layer CAPE
- 4072 J/kg
- Mixed-layer CIN
- -9 J/kg
- Surface CAPE
- 4255 J/kg
- Mixed-layer LCL
- 954 m above ground
- 0-6 km bulk shear
- 46 kt
- 0-1 km bulk shear
- 20 kt
- 0-1 km storm-relative helicity
- 201 m²/s²
- 0-3 km storm-relative helicity
- 377 m²/s²
- Significant tornado parameter
- 7.9
- Supercell composite
- 34.1
- 0-3 km lapse rate
- 7.4 K/km
The surface observations
Enid/Woodring Municipal (WDG), 18 km from the path, in the two hours either side.
| Time (UTC) | Temp (°F) | Dew point (°F) | Wind | Gust (kt) | Pressure (mb) | Weather |
|---|---|---|---|---|---|---|
| 22:00 UTC | 78 | 72 | 170° 15 kt | 25 | 997 | DZ |
| 22:23 UTC | 170° 15 kt | 25 | 996.6 | TS DZ | ||
| 01:00 UTC | 180° 15 kt | 996.3 |
From the Iowa Environmental Mesonet's archive of airport observations.
This ground now
The live radar over the trackEvery 1991 tornado in OklahomaEvery tornado in Oklahoma since 1950Warnings in force in Oklahoma nowThe forecast where you are
The other tornadoes of April 26, 1991
52 more were confirmed in the United States that day.
| Date | Time | Rating | Where | Path (mi) | Width (yd) | Deaths | Injuries | Damage |
|---|---|---|---|---|---|---|---|---|
| April 26 | 6:45 AM CDT | F2 | Kay, OK | 1.0 | 100 | $50,000 to $500,000 | ||
| April 26 | 10:30 AM CDT | F1 | Jefferson Parish, LA | 0.2 | 10 | $5,000 to $50,000 | ||
| April 26 | 10:45 AM CDT | F2 | Montgomery, KS | 6.0 | 100 | $50,000 to $500,000 | ||
| April 26 | 3:25 PM CDT | F2 | Washington, KS | 3.5 | 100 | 6 | $50,000 to $500,000 | |
| April 26 | 3:40 PM CDT | F1 | Fillmore, NE | 1.0 | 50 | $5,000 to $50,000 | ||
| April 26 | 3:45 PM CDT | F0 | Chase, KS | 1.0 | 17 | $500 to $5,000 | ||
| April 26 | 3:50 PM CDT | F3 | Washington, KS to NE | 24.0 | 200 | $50,000 to $500,000 | ||
| April 26 | 4:10 PM CDT | F0 | Morris, KS | 13.0 | 50 | $500,000 to $5 million | ||
| April 26 | 4:35 PM CDT | F2 | Wabaunsee, KS | 44.0 | 200 | $50,000 to $500,000 | ||
| April 26 | 5:00 PM CDT | F2 | Gage, NE | 4.0 | 150 | $50,000 to $500,000 | ||
| April 26 | 5:15 PM CDT | F3 | Otoe, NE | 14.0 | 350 | 2 | $500,000 to $5 million | |
| April 26 | 5:20 PM CDT | F0 | Harper, KS | 1.0 | 50 | $500 to $5,000 | ||
| April 26 | 5:30 PM CDT | F0 | Harper, KS | 16.0 | 50 | $500 to $5,000 | ||
| April 26 | 5:47 PM CDT | F1 | Sedgwick, KS | 2.0 | 50 | $5,000 to $50,000 | ||
| April 26 | 5:57 PM CDT | F5 | Andover tornado, KS | 46.0 | 440 | 17 | 225 | $50 million to $500 million |
| April 26 | 6:00 PM CDT | F3 | Garfield, OK | 6.0 | 350 | $50,000 to $500,000 | ||
| April 26 | 6:10 PM CDT | F1 | Sedgwick, KS | 16.0 | 50 | $5,000 to $50,000 | ||
| April 26 | 6:15 PM CDT | F0 | Pierce, NE | 0.1 | 20 | |||
| April 26 | 6:30 PM CDT | F4 | Garfield, OK | 66.0 | 1,500 | 6 | $500,000 to $5 million | |
| April 26 | 6:30 PM CDT | F4 | Cowley, KS | 25.0 | 500 | 1 | $5 million to $50 million | |
| April 26 | 6:35 PM CDT | F0 | Wabaunsee, KS | 9.0 | 20 | |||
| April 26 | 7:00 PM CDT | F2 | Cherokee, TX | 0.2 | 10 | $50,000 to $500,000 | ||
| April 26 | 7:10 PM CDT | F2 | Butler, KS | 21.0 | 100 | 4 | $50,000 to $500,000 | |
| April 26 | 7:11 PM CDT | F3 | Cherokee, TX | 3.0 | 200 | 1 | $50,000 to $500,000 | |
| April 26 | 7:26 PM CDT | F3 | Elk, KS | 14.0 | 200 | 1 | 2 | $50,000 to $500,000 |
| April 26 | 7:38 PM CDT | F2 | Payne, OK | 6.5 | 800 | $50,000 to $500,000 | ||
| April 26 | 7:40 PM CDT | F0 | Chase, KS | 1.0 | 50 | $500 to $5,000 | ||
| April 26 | 7:40 PM CDT | F2 | Rusk, TX | 3.0 | 100 | $5,000 to $50,000 | ||
| April 26 | 7:44 PM CDT | F1 | Shelby, IA | 2.0 | 47 | $500 to $5,000 | ||
| April 26 | 8:00 PM CDT | F3 | Crawford, IA | 7.7 | 150 | $500,000 to $5 million | ||
| April 26 | 8:00 PM CDT | F2 | Rusk, TX | 0.2 | 10 | $50,000 to $500,000 | ||
| April 26 | 8:10 PM CDT | F4 | Pawnee, OK | 32.0 | 1,700 | 1 | 24 | $500,000 to $5 million |
| April 26 | 8:22 PM CDT | F1 | Rusk, TX | 0.2 | 10 | $500 to $5,000 | ||
| April 26 | 8:27 PM CDT | F1 | Osage, OK | 0.3 | 10 | |||
| April 26 | 8:33 PM CDT | F0 | Sedgwick, KS | 1.0 | 50 | $500 to $5,000 | ||
| April 26 | 8:35 PM CDT | F3 | Greenwood, KS | 15.0 | 50 | $500,000 to $5 million | ||
| April 26 | 8:54 PM CDT | F1 | Shawnee, KS | 11.0 | 20 | 4 | $5,000 to $50,000 | |
| April 26 | 9:00 PM CDT | F2 | Dickinson, IA | 18.0 | 60 | $50,000 to $500,000 | ||
| April 26 | 9:05 PM CDT | F2 | Washington, OK | 6.0 | 100 | 1 | 10 | $50,000 to $500,000 |
| April 26 | 9:25 PM CDT | F2 | Jefferson, KS | 25.0 | 27 | 2 | $500,000 to $5 million | |
| April 26 | 9:45 PM CDT | F4 | Rogers, OK | 4.0 | 1,300 | 22 | $5 million to $50 million | |
| April 26 | 10:00 PM CDT | F2 | Red River, TX | 0.2 | 10 | $50,000 to $500,000 | ||
| April 26 | 10:10 PM CDT | F1 | Rogers, OK | 2.0 | 30 | 3 | $50,000 to $500,000 | |
| April 26 | 10:15 PM CDT | F1 | Andrew, MO | 1.8 | 50 | $5,000 to $50,000 | ||
| April 26 | 10:19 PM CDT | F1 | Red River, TX | 0.2 | 10 | $5,000 to $50,000 | ||
| April 26 | 10:20 PM CDT | F0 | Montgomery, KS | 1.0 | 50 | $5,000 to $50,000 | ||
| April 26 | 10:30 PM CDT | F2 | Red River, TX | 0.2 | 10 | $50,000 to $500,000 | ||
| April 26 | 11:10 PM CDT | F2 | Wayne, IA | 9.0 | 60 | $50,000 to $500,000 | ||
| April 26 | 11:10 PM CDT | F2 | Wayne, IA | 15.0 | 77 | 2 | $500,000 to $5 million | |
| April 26 | 11:39 PM CDT | F0 | Newton, MO | 0.2 | 50 | |||
| April 26 | 11:57 PM CDT | F1 | Andrew, MO | 1.5 | 50 | $500 to $5,000 | ||
| April 26 | 12:05 AM CDT | F0 | Jasper, MO | 0.1 | 10 |
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.