Tornadoes · United States · Texas · 2001
F1 tornado, Muenster to Callisburg, Texas, April 11, 2001
From Muenster to Callisburg, this F1 tornado ran 7.8 miles across Cooke County on April 11, 2001, touching down at 3:34 AM CDT and reaching 100 yards wide. It killed nobody, and did $10,000 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
- April 11, 2001
- Touchdown
- 3:34 AM CDT (08:34 UTC)
- Path length
- 7.8 miles (12.6 km)
- Path width
- 100 yards (91 m)
- Deaths
- 0
- Injuries
- 0
- Property damage
- $10,000
- County
- Cooke County
- Touchdown point
- 33.580, -97.470
- Lift-off point
- 33.650, -97.320
- Record number
- 642
What the Weather Service recorded
April 11th, Episode NarrativeAn upper level low pressure system over West Texas helped initiate thunderstorm development which then moved across North Texas overnight. A squall line with a few embedded supercells moved over the region. The primary severe weather events were wind and hail damage. Supercells along the Red River produced tornadoes in Cooke County before moving north of the Red River into Oklahoma. Numerous reports of damage from strong winds were also received across North Texas.
The second tornado touched down 6.8 miles southwest of Muenster. It then moved northeast and dissipated 3.8 miles east of Muenster. Tree limbs were blown down southwest of Myra and roofs were damaged in Myra.
Tornado number three touched down 4 miles northwest of Gainesville. It then moved into Oklahoma, 6 miles north-northwest of Gainesville (5S Thackerville, OK). A mobile home and a storage shed were heavily damaged northwest of Gainesville.
Tornado number three moved back into Cooke County approximately 6.8 miles northwest of Callisburg(3 ESE Thackerville,Ok) moved northeast and dissipated on the Texas-Oklahoma state line approximately 12 miles North of Callisburg (10 ESE Marietta, Ok) at 0315C. Damage along this part of the track was confined to trees and power lines. See national weather service Norman, Oklahoma storm data for information on the Oklahoma portion of the damage.
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) | Expired | Product | Office |
|---|---|---|---|
| 07:43 UTC | 08:30 UTC | Tornado Warning | FWD |
| 08:33 UTC | 09:30 UTC | Severe Thunderstorm Warning | FWD |
| 08:51 UTC | 09:15 UTC | Tornado Warning | FWD |
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 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.
Fort Worth, TX (KFWD), 00:00Z
8.6 hours before the tornado, 88 km from the path. April 11, 2001.
- Mixed-layer CAPE
- 1205 J/kg
- Mixed-layer CIN
- -116 J/kg
- Surface CAPE
- 2055 J/kg
- Mixed-layer LCL
- 1008 m above ground
- 0-6 km bulk shear
- 64 kt
- 0-1 km bulk shear
- 22 kt
- 0-1 km storm-relative helicity
- 191 m²/s²
- 0-3 km storm-relative helicity
- 261 m²/s²
- Significant tornado parameter
- 1.1
- Supercell composite
- 8.1
- 0-3 km lapse rate
- 5.0 K/km
Fort Worth, TX (KFWD), 12:00Z
3.4 hours after it, 88 km from the path. April 11, 2001.
- Mixed-layer CAPE
- 0 J/kg
- Mixed-layer CIN
- -79450 J/kg
- Surface CAPE
- 0 J/kg
- Mixed-layer LCL
- 2756 m above ground
- 0-6 km bulk shear
- 68 kt
- 0-1 km bulk shear
- 31 kt
- 0-1 km storm-relative helicity
- -242 m²/s²
- 0-3 km storm-relative helicity
- 180 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.8
- 0-3 km lapse rate
- 3.3 K/km
The radar
The Dallas/Ft Worth radar (KFWS), 116 km away, was scanning. The volume nearest the touchdown began at 08:33 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 2001 tornado in TexasEvery tornado in Texas since 1950Warnings in force in Texas nowThe forecast where you are
The other tornadoes of April 11, 2001
49 more were confirmed in the United States that day.
| Date | Time | Rating | Where | Path (mi) | Width (yd) | Deaths | Injuries | Damage |
|---|---|---|---|---|---|---|---|---|
| April 11 | 1:12 AM CDT | F0 | Webster, NE | 3.0 | 25 | $1,000 | ||
| April 11 | 1:14 AM CDT | F1 | Jewell, KS | 17.5 | 75 | $130,000 | ||
| April 11 | 1:30 AM CDT | F1 | Republic, KS | 10.0 | 75 | $20,000 | ||
| April 11 | 1:39 AM CDT | F1 | Nuckolls, NE | 12.0 | 300 | $40,000 | ||
| April 11 | 1:49 AM CDT | F1 | Thayer, NE | 1.0 | 75 | 1 | $30,000 | |
| April 11 | 1:55 AM CDT | F0 | Washington, KS | 6.0 | 75 | $10,000 | ||
| April 11 | 2:05 AM CDT | F1 | Washington, KS | 4.0 | 100 | $10,000 | ||
| April 11 | 2:30 AM CDT | F1 | Gage, NE | 1.0 | 40 | $150,000 | ||
| April 11 | 2:40 AM CDT | F2 | Gage, NE | 2.0 | 50 | 2 | $400,000 | |
| April 11 | 2:47 AM CDT | F1 | Cooke, TX | 5.5 | 50 | $10,000 | ||
| April 11 | 3:00 AM CDT | F1 | Pottawatomie, OK | 5.0 | 50 | $40,000 | ||
| April 11 | 3:55 AM CDT | F1 | Cooke, TX to OK | 19.0 | 150 | $20,000 | ||
| April 11 | 4:40 AM CDT | F2 | Pontotoc, OK | 14.5 | 400 | $520,000 | ||
| April 11 | 4:45 AM CDT | F2 | Johnston, OK | 19.0 | 500 | 4 | $2.5 million | |
| April 11 | 4:47 AM CDT | F0 | Bryan, OK | 0.3 | 25 | $10,000 | ||
| April 11 | 5:25 AM CDT | F2 | Coal, OK | 13.0 | 200 | 1 | 1 | $80,000 |
| April 11 | 7:26 AM CDT | F1 | Haskell, OK | 3.0 | 400 | $100,000 | ||
| April 11 | 10:27 AM CDT | F0 | Cedar, MO | 0.1 | 10 | |||
| April 11 | 11:30 AM CDT | F3 | Worth, MO to IA | 76.5 | 500 | $1.9 million | ||
| April 11 | 12:15 PM CDT | F0 | Sarpy, NE | 0.1 | 30 | $10,000 | ||
| April 11 | 12:37 PM CDT | F0 | Mills, IA | 2.0 | 40 | $20,000 | ||
| April 11 | 12:45 PM CDT | F1 | Mills, IA | 2.0 | 40 | $50,000 | ||
| April 11 | 12:55 PM CDT | F1 | Pottawattamie, IA | 0.5 | 40 | $110,000 | ||
| April 11 | 12:55 PM CDT | F0 | Pottawattamie, IA | 2.0 | 30 | |||
| April 11 | 1:00 PM CDT | F0 | Pottawattamie, IA | 0.2 | 30 | |||
| April 11 | 1:30 PM CDT | F0 | Shelby, IA | 0.2 | 30 | $10,000 | ||
| April 11 | 1:37 PM CDT | F0 | Polk, IA | 0.5 | 35 | |||
| April 11 | 2:25 PM CDT | F1 | Guthrie, IA | 2.0 | 75 | $60,000 | ||
| April 11 | 2:45 PM CDT | F0 | Greene, IA | 0.5 | 25 | |||
| April 11 | 3:04 PM CDT | F0 | Boone, IA | 0.7 | 25 | $10,000 | ||
| April 11 | 3:05 PM CDT | F0 | Greene, IA | 1.0 | 35 | $10,000 | ||
| April 11 | 3:06 PM CDT | F1 | Boone, IA | 3.0 | 140 | $150,000 | ||
| April 11 | 3:10 PM CDT | F1 | Boone, IA | 4.0 | 40 | $70,000 | ||
| April 11 | 3:37 PM CDT | F0 | Webster, IA | 0.2 | 25 | $30,000 | ||
| April 11 | 3:38 PM CDT | F1 | Hamilton, IA | 2.2 | 50 | $70,000 | ||
| April 11 | 3:40 PM CDT | F1 | Jasper, IA | 17.5 | 45 | $10,000 | ||
| April 11 | 4:00 PM CDT | F2 | Wapello, IA | 8.4 | 100 | 2 | 3 | $400,000 |
| April 11 | 4:25 PM CDT | F0 | Keokuk, IA | 3.0 | 50 | $90,000 | ||
| April 11 | 4:40 PM CDT | F0 | Iowa, IA | 0.1 | 10 | |||
| April 11 | 4:50 PM CDT | F0 | Washington, IA | 0.1 | 10 | |||
| April 11 | 5:00 PM CDT | F0 | Johnson, IA | 2.0 | 50 | $30,000 | ||
| April 11 | 5:02 PM CDT | F0 | Johnson, IA | 0.1 | 10 | |||
| April 11 | 5:07 PM CDT | F1 | Black Hawk, IA | 10.0 | 50 | $120,000 | ||
| April 11 | 5:20 PM CDT | F0 | Johnson, IA | 0.1 | 10 | |||
| April 11 | 5:20 PM CDT | F0 | Linn, IA | 0.1 | 10 | |||
| April 11 | 5:20 PM CDT | F0 | Benton, IA | 0.1 | 10 | $20,000 | ||
| April 11 | 5:50 PM CDT | F1 | Fayette, IA | 2.0 | 75 | 1 | $40,000 | |
| April 11 | 7:40 PM EDT | F0 | Muskegon, MI | 0.1 | 20 | |||
| April 11 | 7:42 PM EDT | F0 | Ottawa, MI | 0.1 | 20 |
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.