Tornadoes · United States · Oklahoma · 1997
F1 tornado, Coyle, Oklahoma, October 8, 1997
This F1 tornado ran 0.5 miles across Logan County on October 8, 1997, touching down at 7:15 PM CDT and reaching 23 yards wide. It killed nobody, and did $30,000 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.
F040 to 72 mph
Light damage. Surface peeled off some roofs, gutters and siding damaged, branches broken, shallow-rooted trees pushed over.
F173 to 112 mphthis tornado
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
- F1
- Date
- October 8, 1997
- Touchdown
- 7:15 PM CDT (00:15 UTC)
- Path length
- 0.5 miles (0.8 km)
- Path width
- 23 yards (21 m)
- Deaths
- 0
- Injuries
- 0
- Property damage
- $30,000
- County
- Logan County
- Touchdown point
- 35.820, -97.230
- Lift-off point
- 35.820, -97.230
- Record number
- 1110
What the Weather Service recorded
Summary of events of October 8, 1997:A line of severe thunderstorms developed and moved across western and central Oklahoma during the evening, producing large hail, damaging winds, and 2 tornadoes. The first tornado was observed southeast of billings in Noble County. No damage occurred, and the tornado was rated F0. The second tornado touched down south of Coyle in Logan County, destroying a barn and some outbuildings. Damage was rated F1.The largest hail (up to the size of golf balls) fell in Oklahoma City in Oklahoma County and in Addington in Jefferson County. Severe thunderstorm wind gusts were estimated to be as high as 80 mph (in Perkins in Payne County). Structural wind damage was reported west of White Eagle in Kay County, near Coyle in Payne County, and east of Guthrie in Logan County. Tree damage was reported in Meridian in Logan County, south of Perkins and in Chandler in Lincoln County, in Edmond in Oklahoma County, east of Elgin in Comanche County, and in Marlow in Stephens County.See preceding individual Storm Data entries for further details and additional reports.
A tornado destroyed a barn and outbuildings.
From NOAA NCEI's Storm Events Database, the narrative the local forecast office wrote for Storm Data.
The warnings
25 minutes of warning. NWS OUN issued a tornado warning for this county at 23:50 UTC, 25 minutes before the tornado touched down, in force until 00:30 UTC.
| Issued (UTC) | Expired | Product | Office |
|---|---|---|---|
| 23:30 UTC | 00:15 UTC | Severe Thunderstorm Warning | OUN |
| 23:50 UTC | 00:30 UTC | Tornado Warning | OUN |
| 00:32 UTC | 01:15 UTC | Severe Thunderstorm Warning | OUN |
| 02:00 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 Slight Risk. The outlook in force was issued at 05:34 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), 00:00Z
0.3 hours before the tornado, 68 km from the path. October 9, 1997.
- Mixed-layer CAPE
- 2384 J/kg
- Mixed-layer CIN
- -1 J/kg
- Surface CAPE
- 2846 J/kg
- Mixed-layer LCL
- 800 m above ground
- 0-6 km bulk shear
- 38 kt
- 0-1 km bulk shear
- 18 kt
- 0-1 km storm-relative helicity
- 138 m²/s²
- 0-3 km storm-relative helicity
- 192 m²/s²
- Significant tornado parameter
- 1.7
- Supercell composite
- 9.2
- 0-3 km lapse rate
- 6.8 K/km
Norman, OK (KOUN), 12:00Z
11.7 hours after it, 68 km from the path. October 9, 1997.
- Mixed-layer CAPE
- 27 J/kg
- Mixed-layer CIN
- -149 J/kg
- Surface CAPE
- 0 J/kg
- Mixed-layer LCL
- 1075 m above ground
- 0-6 km bulk shear
- 29 kt
- 0-1 km bulk shear
- 7 kt
- 0-1 km storm-relative helicity
- 13 m²/s²
- 0-3 km storm-relative helicity
- 59 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
- 0-3 km lapse rate
- 4.4 K/km
The radar
The Norman radar (KTLX), 54 km away, was scanning. The volume nearest the touchdown began at 00:13 UTC.
Open the radar archive at this moment, over the track
Reflectivity and velocity, decoded from the Level II archive in the browser. Volumes take a few seconds to open the first time.
This ground now
The live radar over the trackEvery 1997 tornado in OklahomaEvery tornado in Oklahoma since 1950Warnings in force in Oklahoma nowThe forecast where you are
The other tornadoes of October 8, 1997
12 more were confirmed in the United States that day.
| Date | Time | Rating | Where | Path (mi) | Width (yd) | Deaths | Injuries | Damage |
|---|---|---|---|---|---|---|---|---|
| October 8 | 11:23 AM MDT | F0 | Yuma, CO | 1.0 | 30 | |||
| October 8 | 11:25 AM MDT | F0 | Kit Carson, CO | 0.1 | 20 | |||
| October 8 | 11:40 AM MDT | F0 | Kit Carson, CO | 0.3 | 20 | |||
| October 8 | 11:54 AM MDT | F0 | Yuma, CO | 0.2 | 20 | |||
| October 8 | 4:40 PM CDT | F0 | Marion, KS | 0.2 | 23 | |||
| October 8 | 4:46 PM CDT | F0 | Marion, KS | 3.0 | 50 | $100,000 | ||
| October 8 | 5:15 PM CDT | F0 | Riley, KS | 2.5 | 50 | $80,000 | ||
| October 8 | 5:39 PM CDT | F0 | Morris, KS | 0.1 | 30 | |||
| October 8 | 6:15 PM CDT | F0 | Pottawatomie, KS | 0.2 | 73 | |||
| October 8 | 6:20 PM CDT | F0 | Wabaunsee, KS | 1.0 | 30 | |||
| October 8 | 6:31 PM CDT | F0 | Noble, OK | 2.0 | 50 | |||
| October 8 | 7:18 PM CDT | F1 | Atchison, KS | 12.0 | 100 | $150,000 |
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.