Tornadoes · United States · Kansas · 2001

F1 tornado, Courtland to Belleville, Kansas, April 11, 2001

From Courtland to Belleville, this F1 tornado ran 10.0 miles across Republic County on April 11, 2001, touching down at 1:30 AM CDT and reaching 75 yards wide. It killed nobody, and did $20,000 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
April 11, 2001
Touchdown
1:30 AM CDT (06:30 UTC)
Path length
10.0 miles (16.1 km)
Path width
75 yards (69 m)
Deaths
0
Injuries
0
Property damage
$20,000
County
Republic County
Touchdown point
39.750, -97.630
Lift-off point
39.850, -97.450
Record number
87

What the Weather Service recorded

A tornado moved from east central Jewell County into Republic County and struck the town of Courtland before dissipating near the town of Republic. Considerable damage occurred to power lines and farm outbuildings along the path of the tornado. Considerable damage occurred to several buildings in the town of Courtland as well.

A tornado touched down south of Belleville and moved northeast doing intermittant damage along a 10 mile path before dissipating.

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

The warnings

No tornado warning for this county appears in the archive as in force at the moment the tornado touched down. One was issued for the county at another hour that day.

Issued (UTC)ExpiredProductOffice
06:07 UTC06:45 UTCSevere Thunderstorm WarningTOP
06:41 UTC07:15 UTCTornado WarningTOP
06:46 UTC07:30 UTCSevere Thunderstorm WarningTOP

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 05:29 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), 00:00Z

6.5 hours before the tornado, 186 km from the path. April 11, 2001.

Skew-T log-pSkew-T log-p diagram, Topeka, KS at 00:00Z on 2001-04-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 2027 joules per kilogram, CIN -14, lifted condensation level 651 meters above ground. Wind barbs in knots down the right edge.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°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 2001-04-11The 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 342 square meters per square second, 0 to 6 km bulk shear 57 knots.1939587897117Sfc1 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
2027 J/kg
Mixed-layer CIN
-14 J/kg
Surface CAPE
1721 J/kg
Mixed-layer LCL
651 m above ground
0-6 km bulk shear
57 kt
0-1 km bulk shear
32 kt
0-1 km storm-relative helicity
342 m²/s²
0-3 km storm-relative helicity
551 m²/s²
Significant tornado parameter
6.5
Supercell composite
24.9
0-3 km lapse rate
5.5 K/km

Open this sounding in Storm Lab

Topeka, KS (KTOP), 12:00Z

5.5 hours after it, 186 km from the path. April 11, 2001.

Skew-T log-pSkew-T log-p diagram, Topeka, KS at 12:00Z on 2001-04-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 0 joules per kilogram, CIN -15768, lifted condensation level 1312 meters above ground. Wind barbs in knots down the right edge.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°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 2001-04-11The 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 220 square meters per square second, 0 to 6 km bulk shear 69 knots.1939587897117136Sfc1 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
0 J/kg
Mixed-layer CIN
-15768 J/kg
Surface CAPE
38 J/kg
Mixed-layer LCL
1312 m above ground
0-6 km bulk shear
69 kt
0-1 km bulk shear
36 kt
0-1 km storm-relative helicity
220 m²/s²
0-3 km storm-relative helicity
369 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0
0-3 km lapse rate
6.2 K/km

Open this sounding in Storm Lab

The surface observations

Concordia (CNK), 29 km from the path, in the two hours either side.

Time (UTC)Temp (°F)Dew point (°F)WindGust (kt)Pressure (mb)Weather
04:39 UTC64.464.480° 7 kt996.3BR
04:44 UTC64.464.490° 7 kt996.3BR
04:55 UTC6564100° 7 kt996.6BR
05:04 UTC64.464.4100° 6 kt996.6BR
05:28 UTC66.264.4150° 10 kt995.6BR
05:55 UTC6865150° 12 kt994.2
06:32 UTC57.255.4260° 31 kt76997.6+RA BR SQ
06:35 UTC55.453.6260° 21 kt76997.6+RA BR SQ
06:37 UTC55.453.6260° 17 kt40997.6+TSRA BR
06:55 UTC5554240° 15 kt29998+TSRA BR
06:57 UTC55.453.6250° 21 kt29997.3+TSRA BR
07:06 UTC55.453.6260° 17 kt27997.6+TSRA BR
07:28 UTC55.453.6270° 19 kt998.3TSRA
07:55 UTC5653280° 12 kt997.6TSRA BR
08:06 UTC55.453.6300° 9 kt17997TSRA BR
08:28 UTC55.453.6330° 7 kt997+TSRA BR

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

This ground now

The live radar over the trackEvery 2001 tornado in KansasEvery tornado in Kansas since 1950Warnings in force in Kansas nowThe forecast where you are

The other tornadoes of April 11, 2001

49 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
April 111:12 AM CDTF0Webster, NE3.025$1,000
April 111:14 AM CDTF1Jewell, KS17.575$130,000
April 111:39 AM CDTF1Nuckolls, NE12.0300$40,000
April 111:49 AM CDTF1Thayer, NE1.0751$30,000
April 111:55 AM CDTF0Washington, KS6.075$10,000
April 112:05 AM CDTF1Washington, KS4.0100$10,000
April 112:30 AM CDTF1Gage, NE1.040$150,000
April 112:40 AM CDTF2Gage, NE2.0502$400,000
April 112:47 AM CDTF1Cooke, TX5.550$10,000
April 113:00 AM CDTF1Pottawatomie, OK5.050$40,000
April 113:34 AM CDTF1Cooke, TX7.8100$10,000
April 113:55 AM CDTF1Cooke, TX to OK19.0150$20,000
April 114:40 AM CDTF2Pontotoc, OK14.5400$520,000
April 114:45 AM CDTF2Johnston, OK19.05004$2.5 million
April 114:47 AM CDTF0Bryan, OK0.325$10,000
April 115:25 AM CDTF2Coal, OK13.020011$80,000
April 117:26 AM CDTF1Haskell, OK3.0400$100,000
April 1110:27 AM CDTF0Cedar, MO0.110
April 1111:30 AM CDTF3Worth, MO to IA76.5500$1.9 million
April 1112:15 PM CDTF0Sarpy, NE0.130$10,000
April 1112:37 PM CDTF0Mills, IA2.040$20,000
April 1112:45 PM CDTF1Mills, IA2.040$50,000
April 1112:55 PM CDTF1Pottawattamie, IA0.540$110,000
April 1112:55 PM CDTF0Pottawattamie, IA2.030
April 111:00 PM CDTF0Pottawattamie, IA0.230
April 111:30 PM CDTF0Shelby, IA0.230$10,000
April 111:37 PM CDTF0Polk, IA0.535
April 112:25 PM CDTF1Guthrie, IA2.075$60,000
April 112:45 PM CDTF0Greene, IA0.525
April 113:04 PM CDTF0Boone, IA0.725$10,000
April 113:05 PM CDTF0Greene, IA1.035$10,000
April 113:06 PM CDTF1Boone, IA3.0140$150,000
April 113:10 PM CDTF1Boone, IA4.040$70,000
April 113:37 PM CDTF0Webster, IA0.225$30,000
April 113:38 PM CDTF1Hamilton, IA2.250$70,000
April 113:40 PM CDTF1Jasper, IA17.545$10,000
April 114:00 PM CDTF2Wapello, IA8.410023$400,000
April 114:25 PM CDTF0Keokuk, IA3.050$90,000
April 114:40 PM CDTF0Iowa, IA0.110
April 114:50 PM CDTF0Washington, IA0.110
April 115:00 PM CDTF0Johnson, IA2.050$30,000
April 115:02 PM CDTF0Johnson, IA0.110
April 115:07 PM CDTF1Black Hawk, IA10.050$120,000
April 115:20 PM CDTF0Johnson, IA0.110
April 115:20 PM CDTF0Linn, IA0.110
April 115:20 PM CDTF0Benton, IA0.110$20,000
April 115:50 PM CDTF1Fayette, IA2.0751$40,000
April 117:40 PM EDTF0Muskegon, MI0.120
April 117:42 PM EDTF0Ottawa, MI0.120

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.