EF1 tornado, Bison to Pfeifer, Kansas, May 25, 2012

1. EF065 to 85 mph

   Light damage. Surface peeled off some roofs, gutters and siding damaged, branches broken, shallow-rooted trees pushed over.

2. EF186 to 110 mphthis tornado

   Moderate damage. Roofs badly stripped, mobile homes overturned or badly damaged, exterior doors lost, windows broken.

3. EF2111 to 135 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. EF3136 to 165 mph

   Severe damage. Whole stories of well-built houses destroyed, large buildings badly damaged, trains overturned, trees debarked, heavy cars lifted and thrown.

5. EF4166 to 200 mph

   Devastating damage. Well-built houses leveled, structures with weak foundations moved some distance, cars thrown and large missiles generated.

6. EF5over 200 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

EF1

Date

May 25, 2012

Touchdown

10:35 PM CDT (03:35 UTC)

Lifted

10:42 PM CDT (03:42 UTC)

On the ground

7 minutes

Path length

2.8 miles (4.5 km)

Path width

200 yards (183 m)

Deaths

0

Injuries

0

Counties

Rush and Ellis counties

Touchdown point

38.667, -99.140

Lift-off point

38.705, -99.156

Record number

1205252135-01

A warm front lifting north under very cold temperatures aloft was the focus of severe thunderstorms during the late afternoon and evening. Tornadoes produced scattered damage.

This tornado starting moving north then turned back to the northwest and finally west before dissipating. It did damage mainly to trees and power lines. During the damage survey there was evidence of significant ground and vegetation scouring.

Damage was done to trees from this tornado.

This tornado moved into Ellis county at 10:40 CDT.

This tornado moved out of Rush county at 10:40 PM CDT and did damage to trees and power poles.

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

12 minutes of warning. NWS DDC issued a tornado warning for this county at 03:23 UTC, 12 minutes before the tornado touched down, in force until 04:00 UTC.

The county was under a tornado watch, issued at 23:48 UTC and running to 05:01 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 Slight Risk, with a 0.05 chance of a tornado within 25 miles. The outlook in force was issued at 00:57 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 Dodge City radar (KDDC), 125 km away, was scanning. The volume nearest the touchdown began at 03:37 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 2012 tornado in KansasEvery tornado in Kansas since 1950Warnings in force in Kansas nowThe forecast where you are

12 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.