EF1 tornado, St George to Grant Park, Illinois, March 8, 2009

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

March 8, 2009

Touchdown

1:56 PM CDT (18:56 UTC)

Lifted

1:58 PM CDT (18:58 UTC)

On the ground

2 minutes

Path length

0.7 miles (1.2 km)

Path width

80 yards (73 m)

Deaths

0

Injuries

0

Property damage

$40,000

County

Kankakee County

Touchdown point

41.191, -87.736

Lift-off point

41.196, -87.723

Record number

0903081256-01

Strong to severe thunderstorms moved across northern Illinois during the morning and afternoon hours of March 8th. Heavy rain and flooding were also reported.

An EF1 tornado touched down near the intersection of county roads 5000N and 7500E. On the southwest corner of this intersection, a detached garage and steel shed were destroyed. A two foot diameter tree was snapped at the base and several other trees had large branches broken off. Debris from this location was lifted and carried approximately 100 yards into the field across the road. The tornado also damaged property on the northeast corner of the intersection. A corn crib and a shed which served as a blacksmith forge were both destroyed. Debris from these buildings was scattered to the northeast in a narrow path approximately 800 yards long. Corn stalks in a field to the northeast appeared to have been flattened and twisted by this tornado.

A tornado touched down at a farm about one half mile east of the intersection of county roads 8000N and 9000E. Two barns at this location lost part of their roof. Another garage and another steel building were completely destroyed. Debris from this location was lifted and deposited in a field and treeline approximately 400 yards to the northeast.

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

1 minute of warning. NWS LOT issued a tornado warning for this county at 18:55 UTC, 1 minute before the tornado touched down, in force until 19:49 UTC.

The county was under a tornado watch, issued at 15:39 UTC and running to 20:25 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 16:26 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.

Kankakee (IKK), 17 km from the path, in the two hours either side.

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

The Chicago radar (KLOT), 54 km away, was scanning. The volume nearest the touchdown began at 18:56 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 2009 tornado in IllinoisEvery tornado in Illinois since 1950Warnings in force in Illinois nowThe forecast where you are

25 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.