EF1 tornado, Tovey to Willeys, Illinois, April 19, 2011

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 19, 2011

Touchdown

6:17 PM CDT (23:17 UTC)

Lifted

6:20 PM CDT (23:20 UTC)

On the ground

3 minutes

Path length

2.0 miles (3.2 km)

Path width

100 yards (91 m)

Deaths

0

Injuries

0

Property damage

$90,000

County

Christian County

Touchdown point

39.546, -89.462

Lift-off point

39.554, -89.425

Record number

1104191717-01

1 damage points were recorded along this path by NWS LSX, in the Damage Assessment Toolkit the survey teams carry. The highest wind the damage implies is 75 mph.

• Rotted tree limb broken from what appears to be RFD winds.

Survey points are preliminary and are the raw material the published rating was built from. Source: NWS Damage Assessment Toolkit.

A deepening area of low pressure tracked along the I-72 corridor during the evening of April 19th. A very sharp temperature gradient existed across central Illinois at the time, with readings ranging from the middle 40s north of the low track to around 80 degrees to the south. Severe thunderstorms developed along this strong frontal boundary in advance of the approaching low, producing widespread wind damage and large hail. In addition, 6 tornadoes touched down from Christian County east-northeast into Vermilion and Edgar counties.

A tornado touched down 4 miles southwest of Kincaid at 517 PM CST. It destroyed several grain bins and a large farm storage building before dissipating 2.5 miles south-southwest of Kincaid at 520 PM CST.

A tornado touched down 2 miles northeast of Taylorville at 532 PM CST. It traveled eastward, knocking over 8 empty rail cars before dissipating 2.5 miles northeast of Taylorville at 533 PM CST.

A tornado touched down 4 miles southwest of Morrisonville at 530 PM CST. It traveled eastward, knocking down several power poles along Rt. 48. The tornado then tore the roof off a hog pen, collapsed the north doors of a large metal farm building, and destroyed a small barn before dissipating 3 miles south of Morrisonville at 532 PM CST.

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

5 minutes of warning. NWS ILX issued a tornado warning for this county at 23:12 UTC, 5 minutes before the tornado touched down, in force until 23:48 UTC.

The county was under a tornado watch, issued at 18:05 UTC and running to 01:54 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 Moderate Risk, with a 0.10 chance of a tornado within 25 miles, in the hatched area where significant tornadoes were expected. The outlook in force was issued at 19:37 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.

Taylorville (TAZ), 10 km from the path, in the two hours either side.

From the Iowa Environmental Mesonet's archive of airport observations.

The Lincoln radar (KILX), 67 km away, was scanning. The volume nearest the touchdown began at 23:16 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 2011 tornado in IllinoisEvery tornado in Illinois since 1950Warnings in force in Illinois nowThe forecast where you are

69 more were confirmed in the United States that day.

All 70 of them

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.