EF1 tornado, Johnson, Nebraska, April 24, 2008

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

April 24, 2008

Touchdown

12:50 AM CDT (05:50 UTC)

Lifted

12:53 AM CDT (05:53 UTC)

On the ground

3 minutes

Path length

0.3 miles (0.5 km)

Path width

100 yards (91 m)

Deaths

0

Injuries

0

Property damage

$100,000

County

Nemaha County

Touchdown point

40.410, -96.000

Lift-off point

40.413, -95.995

Record number

0804242350-01

An area of thunderstorms, including a few supercells, developed along a cold front that was pushing into eastern Nebraska and also along a weak warm front that extended just ahead of the cold front. The storms were fed by a very strong low level jet that increased in intensity and helped create the wind shear favorable for the supercells, including one which produced a short-lived tornado in Johnson, Nebraska. The storms also produced a small area of very heavy rain. Virginia in Gage county reported around 4 inches with a little over 2 inches reported in Tecumseh which is in Johnson county. The heavy rain produced isolated flash flooding and river flooding.||This weather system eventually produced 3 to 8 inches or more of heavy wet snow on April 25th from northern Nebraska into North Dakota and western Minnesota. Freezing rain was also reported over sections of eastern South Dakota from this storm.

A tornado touched down on the southwest edge of Johnson near Chestnut and 1st Streets. The tornado moved northeast across town causing EF1 damage to several buildings in downtown Johnson along Main Street between 2nd and 3rd Streets. The tornado weakened as it approached the high school and then lifted around Walnut and 5th Streets.||Roofing material and the facade of several buildings were peeled or collapsed. Hardwood and softwood trees were snapped along the path and 2 garages were pushed off of their foundations. A building next to the fire station also had a large garage door blown in. No injuries were reported.

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

9 minutes of warning. NWS OAX issued a tornado warning for this county at 05:41 UTC, 9 minutes before the tornado touched down, in force until 06:15 UTC.

The county was under a severe thunderstorm watch, issued at 03:20 UTC and running to 06:14 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 0.02 chance of a tornado within 25 miles. The outlook in force was issued at 01:00 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 Omaha radar (KOAX), 106 km away, was scanning. The volume nearest the touchdown began at 05:50 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 2008 tornado in NebraskaEvery tornado in Nebraska since 1950Warnings in force in Nebraska nowThe forecast where you are

6 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.