Tornadoes · United States · Kansas · 2005

F0 tornado, Atchison, Kansas, April 21, 2005

This F0 tornado ran 2.0 miles across Atchison County on April 21, 2005, touching down at 5:10 PM CDT and reaching 50 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
April 21, 2005
Touchdown
5:10 PM CDT (22:10 UTC)
Path length
2.0 miles (3.2 km)
Path width
50 yards (46 m)
Deaths
0
Injuries
0
County
Atchison County
Touchdown point
39.420, -95.130
Lift-off point
39.430, -95.070
Record number
727

What the Weather Service recorded

Brief tornado touchdown wrapped in rain, photographed by storm chaser in open country.

Tornado videotaped by storm chaser and observed by Leavenworth Co. EMA in open country.

From NOAA NCEI's Storm Events Database, the narrative the local forecast office wrote for Storm Data.

The warnings

22 minutes of warning. NWS EAX issued a tornado warning for this county at 21:48 UTC, 22 minutes before the tornado touched down, in force until 22:28 UTC.

Issued (UTC)ExpiredProductOffice
21:12 UTC22:00 UTCTornado WarningEAX
21:48 UTC22:28 UTCTornado WarningEAX
22:05 UTC22:45 UTCTornado WarningEAX
22:46 UTC23:10 UTCSevere Thunderstorm WarningEAX

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, with a 0.05 chance of a tornado within 25 miles. The outlook in force was issued at 19:49 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.

Topeka, KS (KTOP), 12:00Z

10.2 hours before the tornado, 66 km from the path. April 21, 2005.

Skew-T log-pSkew-T log-p diagram, Topeka, KS at 12:00Z on 2005-04-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 626 joules per kilogram, CIN -159, lifted condensation level 789 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, Topeka, KS at 12:00Z on 2005-04-21The 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 87 square meters per square second, 0 to 6 km bulk shear 38 knots.193958Sfc1 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
626 J/kg
Mixed-layer CIN
-159 J/kg
Surface CAPE
619 J/kg
Mixed-layer LCL
789 m above ground
0-6 km bulk shear
38 kt
0-1 km bulk shear
12 kt
0-1 km storm-relative helicity
87 m²/s²
0-3 km storm-relative helicity
156 m²/s²
Significant tornado parameter
0.1
Supercell composite
0.4
0-3 km lapse rate
5.3 K/km

Open this sounding in Storm Lab

Topeka, KS (KTOP), 00:00Z

1.8 hours after it, 66 km from the path. April 22, 2005.

Skew-T log-pSkew-T log-p diagram, Topeka, KS at 00:00Z on 2005-04-22Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 795 joules per kilogram, CIN -4, lifted condensation level 1802 meters above ground. Wind barbs in knots down the right edge.LCLEL10008507005003002001001 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, Topeka, KS at 00:00Z on 2005-04-22The 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 19 square meters per square second, 0 to 6 km bulk shear 42 knots.19395878Sfc1 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
795 J/kg
Mixed-layer CIN
-4 J/kg
Surface CAPE
1164 J/kg
Mixed-layer LCL
1802 m above ground
0-6 km bulk shear
42 kt
0-1 km bulk shear
16 kt
0-1 km storm-relative helicity
19 m²/s²
0-3 km storm-relative helicity
35 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.6
0-3 km lapse rate
8.1 K/km

Open this sounding in Storm Lab

The surface observations

Fort Leavenworth (FLV), 17 km from the path, in the two hours either side.

Time (UTC)Temp (°F)Dew point (°F)WindGust (kt)Pressure (mb)Weather
20:53 UTC8061140° 10 kt1007.5
21:53 UTC7663100° 12 kt1006.1
22:30 UTC73.462.680° 19 kt241002.4-TSRA
22:44 UTC66.262.6300° 23 kt301006.8-TSRA BR
22:53 UTC6461290° 13 kt311006.8-TSRA FG
22:56 UTC64.462.6250° 8 kt311006.8-TSRA BR
23:03 UTC64.462.6 4 kt1006.8-TSRA
23:11 UTC64.460.8240° 5 kt1007.1-TSRA
23:38 UTC60.85930° 12 kt1007.1-TSRA
23:53 UTC636140° 13 kt1006.8-RA

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

The radar

The Pleasant Hill radar (KEAX), 99 km away, was scanning. The volume nearest the touchdown began at 22:09 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 2005 tornado in KansasEvery tornado in Kansas since 1950Warnings in force in Kansas nowThe forecast where you are

The other tornadoes of April 21, 2005

11 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
April 213:48 PM CDTF0Nemaha, KS0.125
April 214:19 PM CDTF0Crawford, KS0.250
April 215:04 PM CDTF0Atchison, KS0.550
April 215:54 PM CDTF3Neosho, KS5.0200$200,000
April 216:05 PM CDTF0Cherokee, KS0.120
April 216:19 PM CDTF1Neosho, KS7.0100$10,000
April 216:34 PM CDTF0Labette, KS0.555
April 216:53 PM CDTF0Tom Green, TX0.530
April 217:48 PM CDTF0Rogers, OK0.130
April 217:50 PM CDTF0Jackson, MO2.050
April 218:30 PM CDTF0Wagoner, OK0.130

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.