EF1 tornado, Swan to Mt Zion, Missouri, May 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

May 8, 2009

Touchdown

8:25 AM CDT (13:25 UTC)

Lifted

8:38 AM CDT (13:38 UTC)

On the ground

13 minutes

Path length

12.3 miles (19.7 km)

Path width

880 yards (805 m)

Deaths

0

Injuries

0

Property damage

$2.6 million

Counties

Taney, Christian and Douglas counties

Touchdown point

36.778, -93.030

Lift-off point

36.892, -92.868

Record number

0905080725-01

An intense squall line impacted extreme southeast Kansas and the Missouri Ozarks with mainly damaging winds. However, 19 tornadoes along with large hail was also observed. Due to the straight line nature of the winds, damage was widespread and intense.

A tornado touched down in rural sections of the county and caused damage to a home and numerous outbuildings on Essray Road. Intense tree damage also occurred as the tornado tracked into southeastern Christian County.

This tornado is an extension of the Taney County tornado. A National Weather Service storm survey revealed that an EF-1 tornado impacted extreme southeast Christian County. Wind speeds were estimated at 100 mph as the tornado damaged two homes, destroyed a few outbuildings, and downed numerous trees. The tornado eventually tracked into western Douglas County.

This tornado is an extension of the Christian County tornado. A National Weather Service storm survey revealed that an EF-1 tornado tracked into southwest Douglas County. Trees and a few outbuildings were damaged from the tornado.

A National Weather Service storm survey revealed that an EF-2 tornado with winds up to 130 mph touched down approximately one mile north of Merritt. The tornado tracked northeast along a two and a half mile path before lifting northwest of Goodhope. The tornado damaged two homes, several outbuildings, and numerous trees.

A National Weather Service storm survey revealed that an EF-2 tornado touched down two miles west of Goodhope and tracked northeast for about two and a half miles. The tornado tore a roof off of a home along with damaging numerous trees.

A National Weather Service storm survey revealed that an EF-1 tornado touched down near Mt. Zion and tracked about one mile to the northeast. The tornado caused minor home damage, destroyed a barn, and uprooted several trees.

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

1 minute of warning. NWS SGF issued a tornado warning for this county at 13:24 UTC, 1 minute before the tornado touched down, in force until 13:52 UTC.

The county was under a severe thunderstorm watch, issued at 09:58 UTC and running to 14:49 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 0.05 chance of a tornado within 25 miles. The outlook in force was issued at 12:10 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 Springfield radar (KSGF), 60 km away, was scanning. The volume nearest the touchdown began at 13:25 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 MissouriEvery tornado in Missouri since 1950Warnings in force in Missouri nowThe forecast where you are

45 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.