EF1 tornado, Clinch to Old Duquoin, Illinois, June 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

June 19, 2011

Touchdown

3:48 AM CDT (08:48 UTC)

Lifted

3:51 AM CDT (08:51 UTC)

On the ground

3 minutes

Path length

3.2 miles (5.2 km)

Path width

250 yards (229 m)

Deaths

0

Injuries

1

Property damage

$550,000

County

Perry County

Touchdown point

37.972, -89.252

Lift-off point

37.988, -89.196

Record number

1106190248-01

A long-lived bow echo raced eastward across parts of southern Illinois at 60 mph. An extensive rain shield in the wake of the fast-moving line of storms supported development of a cold pool that sustained its growth. A corridor of moderate instability existed in advance of the storms. A 40 to 50-knot southwesterly low-level jet veered more westerly, further aiding in the eastward movement of the bow echo. A westerly rear-inflow jet around 70 knots developed attendant to the developing bow echo. Vertically veering low-level winds promoted the formation of an isolated tornado along the leading edge of the bow echo.

A tornado crossed through the DuQuoin State Fairgrounds, where damage was estimated around one-half million dollars. Dozens of large trees were snapped or uprooted. Several small camper trailers were overturned. One unoccupied trailer was demolished. Three persons were trapped inside a camper at the DuQuoin State Fairgrounds. They were extricated by fire and rescue personnel. One person sustained minor injuries in an overturned trailer. Several homes lost some shingles and sustained mainly minor damage from fallen trees. At the state fairgrounds, a shower/restroom facility and the Farm Service building were destroyed by falling trees. Large hvac units were lifted off the roof of the main arena building and overturned. The doors of the building were damaged. A couple of uprooted trees ruptured gas lines. The peak winds were estimated near 100 mph. The average path width was 200 yards.

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

20 minutes of warning. NWS PAH issued a tornado warning for this county at 08:28 UTC, 20 minutes before the tornado touched down, in force until 09:00 UTC.

The county was under a tornado watch, issued at 07:55 UTC and running to 11:01 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 0.02 chance of a tornado within 25 miles. The outlook in force was issued at 06:00 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 Paducah radar (KPAH), 109 km away, was scanning. The volume nearest the touchdown began at 08:49 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

13 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.