F1 tornado, Longford to Clay Center, Kansas, April 6, 2006

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 6, 2006

Touchdown

4:40 PM CDT (21:40 UTC)

Path length

9.0 miles (14.5 km)

Path width

880 yards (805 m)

Deaths

0

Injuries

0

Property damage

$100,000

County

Clay County

Touchdown point

39.380, -97.150

Lift-off point

39.480, -97.150

Record number

284

This tornado formed 4 miles east-northeast of Longford at 3:13pm cst and stayed on the ground for 1 mile before disipating 5 miles east-northeast of Longford at 3:15pm cst. It was an F0 tornado with a path width of 100 yards. Damage was only to trees. It was caused by a supercell thunderstorm. This tornado was reported as being briefly on the ground at the same time as the tornado 5 miles northeast of Longford.

This tornado formed 5 miles northeast of Longford at 3:14pm cst and travelled 4 miles before lifting 9 miles northeast of Longford at 3:19pm cst. It was an F0 tornado with a path width of 100 yards that caused damage to 3 outbuildings and downed a large tree. It formed from a supercell thunderstorm. The tornado was reported as being on the ground briefly at the same time as the tornado 4 miles east-northeast of Longford by a storm chaser.

This tornado formed from a supercell thunderstorm 2 miles west of Clay Center at 3:40pm cst and travelled 9 miles before lifting 2 miles south-southwest of Garfield Center at 3:52pm cst. The tornado was up to 1/2 mile wide at times and damaged numerous outbuildings, trees, roofs, and irrigation pivots along its path. It was rated as a strong F1 tornado.

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

45 minutes of warning. NWS TOP issued a tornado warning for this county at 20:55 UTC, 45 minutes before the tornado touched down, in force until 21:45 UTC.

The county was under a tornado watch, issued at 17:46 UTC and running to 00:08 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 Storm Prediction Center had this point in a High Risk, with a 0.30 chance of a tornado within 25 miles, in the hatched area where significant tornadoes were expected. The outlook in force was issued at 20:09 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 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 Topeka radar (KTWX), 93 km away, was scanning. The volume nearest the touchdown began at 21:41 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.

Local storm reports within 60 km of the path, in the three hours either side.

From the Iowa Environmental Mesonet's archive of National Weather Service local storm reports.

The live radar over the trackEvery 2006 tornado in KansasEvery tornado in Kansas since 1950Warnings in force in Kansas nowThe forecast where you are

11 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.