F1 tornado, Mozier, Illinois, February 11, 1999

1. F040 to 72 mph

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

2. F173 to 112 mphthis tornado

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

3. F2113 to 157 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. F3158 to 206 mph

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

5. F4207 to 260 mph

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

6. F5261 to 318 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

F1

Date

February 11, 1999

Touchdown

2:06 PM CST (20:06 UTC)

Path length

3.0 miles (4.8 km)

Path width

50 yards (46 m)

Deaths

0

Injuries

0

Property damage

$100,000

County

Calhoun County

Touchdown point

39.350, -90.780

Lift-off point

39.370, -90.720

Record number

147

The Annada, MO tornado crossed the Mississippi River west of Mozier and continued northeast for about 9 miles across Calhoun County, IL. The tornado reached a maximum intensity of F2 with a damage path up to 100 yards wide. The tornado first damaged a home as it crossed Highway 96 north of Mozier. A 2 car garage was destroyed, the porch destroyed and several windows were blown out. The tornado moved northeast up West Panther Creek Hollow where it reached F2 intensity. One home was destroyed with only 2 walls left standing. 2 x 4 boards became missiles with several driven into walls and into the ground. Half of the roof of another nearby home was also blown off. 3 other homes suffered minor damage. Several outbuildings were also destroyed and numerous trees were uprooted along the path.

A small tornado formed north of Mozier, north of the Annada tornado, and tracked east northeast along Belleview Hollow. An 80 foot long hog sleeping station was destroyed along with a utility shed. This was the second year in a row that this hog farm had been hit by a tornado. The tornado also damaged a barn, several other utility buildings and a home at another farm. Flying metal injured a horse at the farm as well.

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

10 minutes of warning. NWS LSX issued a tornado warning for this county at 19:56 UTC, 10 minutes before the tornado touched down, in force until 20:45 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. The outlook in force was issued at 11:21 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 St Louis radar (KLSX), 74 km away, was scanning. The volume nearest the touchdown began at 20:07 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.

The live radar over the trackEvery 1999 tornado in IllinoisEvery tornado in Illinois since 1950Warnings in force in Illinois nowThe forecast where you are

4 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.