F1 tornado, Pittsburg to Stockport, Iowa, April 2, 2006

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

April 2, 2006

Touchdown

4:15 PM CDT (21:15 UTC)

Path length

2.0 miles (3.2 km)

Path width

50 yards (46 m)

Deaths

0

Injuries

0

Property damage

$10,000

County

Van Buren County

Touchdown point

40.800, -91.920

Lift-off point

40.820, -91.880

Record number

214

Tornado touched down about 0.5 miles west of Pittsburg near a cemetery and continued northeast for 3 miles just along the west edge of the Des Moines River. Along this path, 2 homes were unroofed and 4 outbuildings were destroyed. Many trees were snapped or uprooted and power poles were blown down.

The second tornado of a cyclic supercell developed 0.7 miles north of Mt Zion and moved northeast for 2 miles and dissipated shortly after crossing highway 16 2.2 miles south of Winchester or 2.6 miles northeast of Mt Zion. A roof was blown off a barn with minor roof damage to a house. Several outbuildings were destroyed with tree damage noted.

The third tornado of a cyclic supercell produced an F1 tornado in Stockport and moved northeast for 3 miles before dissipating. Several outbuildings and trees were either destroyed or damaged.

Rated F2.

Rated F1

Rated F1

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

1 minute of warning. NWS DVN issued a tornado warning for this county at 21:14 UTC, 1 minute before the tornado touched down, in force until 22:00 UTC.

The county was under a tornado watch, issued at 17:30 UTC and running to 23:27 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 19:55 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 Quad Cities radar (KDVN), 142 km away, was scanning. The volume nearest the touchdown began at 21:15 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 2006 tornado in IowaEvery tornado in Iowa since 1950Warnings in force in Iowa nowThe forecast where you are

66 more were confirmed in the United States that day.

All 67 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.