Tornadoes · United States · Kansas · 1999
F1 tornado, Osborne, Kansas, May 22, 1999
This F1 tornado ran 6.0 miles across Osborne County on May 22, 1999, touching down at 9:30 PM CDT and reaching 50 yards wide. It killed nobody, and did $40,000 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
- May 22, 1999
- Touchdown
- 9:30 PM CDT (02:30 UTC)
- Path length
- 6.0 miles (9.7 km)
- Path width
- 50 yards (46 m)
- Deaths
- 0
- Injuries
- 0
- Property damage
- $40,000
- County
- Osborne County
- Touchdown point
- 39.380, -98.630
- Lift-off point
- 39.430, -98.580
- Record number
- 361
What the Weather Service recorded
Very severe thunderstorms rolled southeast across north-central Kansas spawning a tornado and causing extensive crop damage. The tornado was reported southeast of Osborne and passed directly over at least one farm. The siding was torn from the home, implements were twisted and blown up to one quarter mile from their original position. The tornado caused extensive tree damage as it moved northeast along the Indian Creek basin.Hail and wind was the problem across Smith county. Wind driven hail, up to 3 inches in diameter, caused millions in crop loss near Cora. The storm also damaged crops in extreme eastern Phillips county. Though not quite as extensive, similar damage was reported in Osborne and Mitchell counties from the wind, hail and heavy rains.
From NOAA NCEI's Storm Events Database, the narrative the local forecast office wrote for Storm Data.
The warnings
5 minutes of warning. NWS GID issued a tornado warning for this county at 02:25 UTC, 5 minutes before the tornado touched down, in force until 03:00 UTC.
| Issued (UTC) | Expired | Product | Office |
|---|---|---|---|
| 01:52 UTC | 02:45 UTC | Severe Thunderstorm Warning | GID |
| 02:25 UTC | 03:00 UTC | Tornado Warning | GID |
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 Moderate Risk. The outlook in force was issued at 01:03 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.
Dodge City, (KDDC), 00:00Z
2.5 hours before the tornado, 214 km from the path. May 23, 1999.
- Mixed-layer CAPE
- 3327 J/kg
- Mixed-layer CIN
- -15 J/kg
- Surface CAPE
- 4199 J/kg
- Mixed-layer LCL
- 1179 m above ground
- 0-6 km bulk shear
- 34 kt
- 0-1 km bulk shear
- 20 kt
- 0-1 km storm-relative helicity
- 138 m²/s²
- 0-3 km storm-relative helicity
- 277 m²/s²
- Significant tornado parameter
- 3.1
- Supercell composite
- 23.4
- 0-3 km lapse rate
- 7.3 K/km
Dodge City, (KDDC), 12:00Z
9.5 hours after it, 214 km from the path. May 23, 1999.
- Mixed-layer CAPE
- 0 J/kg
- Mixed-layer CIN
- -2 J/kg
- Surface CAPE
- 14 J/kg
- Mixed-layer LCL
- 571 m above ground
- 0-6 km bulk shear
- 43 kt
- 0-1 km bulk shear
- 19 kt
- 0-1 km storm-relative helicity
- -105 m²/s²
- 0-3 km storm-relative helicity
- -7 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
- 0-3 km lapse rate
- 4.6 K/km
This ground now
The live radar over the trackEvery 1999 tornado in KansasEvery tornado in Kansas since 1950Warnings in force in Kansas nowThe forecast where you are
The other tornadoes of May 22, 1999
3 more were confirmed in the United States that day.
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.