F1 tornado, Gainesville to Callisburg, Texas, April 11, 2001

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.

Rating

F1

Date

April 11, 2001

Touchdown

3:55 AM CDT (08:55 UTC)

Path length

19.0 miles (30.6 km)

Path width

150 yards (137 m)

Deaths

0

Injuries

0

Property damage

$20,000

Counties

Cooke and Love counties

Touchdown point

33.670, -97.200

Lift-off point

33.870, -97.020

Record number

616

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.

Six tornadoes across southern Oklahoma and one tornado across western north Texas developed during the overnight hours of the 11th. The most notable tornado formed across Coal County in Oklahoma and resulted in one fatality and one injury as it destroyed a mobile home. In addition to damage produced by severe thunderstorms, sustained winds of 40 to 50 mph with gusts as high as 73 mph developed just ahead of the most frequent period of severe weather and persisted for several hours. In Tillman County, at 2330 CST on the 10th, a barn roof was damaged 3 miles east of Frederick. A barn roof was blown off, and a fence was downed 4 miles east of Frederick, and a house roof sustained minor damage 4 miles north of Frederick. Trees and power lines were downed in Ponca City in Kay County, while in Garfield County, minor but widespread damage, was sustained to trees, power poles, and numerous other structures.

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.

This tornado developed in Cooke County Texas at approximately 0257 CST and tracked northeastward for approximately 1 mile before crossing the Red River into Love County in Oklahoma (see National Weather Service Forth Worth, Texas stormdata for more information on the beginning portion of this tornado in Texas). In Oklahoma the most significant damage, rated F1, occurred 3 miles southeast of Thackerville where a barn was destroyed, and a mobile home was severely damaged with debris scattered for 2 miles.Note to all users: This is a greatly simplified version of the tornado path. The tornado actually crossed the state border 6 times, continuing almost due northeastward from the end point listed in this entry. The true end point is 10 miles east-southeast of Marietta, Oklahoma at 0315 CST, resulting in a total path length across Texas and Oklahoma of approximately 18 miles, with most of the damage consisting of only tree damage for the last 10 miles.

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.

4 minutes of warning. NWS FWD issued a tornado warning for this county at 08:51 UTC, 4 minutes before the tornado touched down, in force until 09:15 UTC.

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 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.

The Dallas/Ft Worth radar (KFWS), 134 km away, was scanning. The volume nearest the touchdown began at 08:56 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.

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

49 more were confirmed in the United States that day.

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.

NOAA Storm Prediction Center tornado database, 1950-2025, the official record kept by NOAA's Storm Prediction Center.