Tornadoes · United States · Missouri · 2007

EF0 tornado, Clever, Missouri, September 6, 2007

This EF0 tornado ran 0.5 miles across Christian County on September 6, 2007, touching down at 5:20 AM CDT and reaching 50 yards wide. It killed nobody, and did $2,000 of property damage.

The rating scale

Tracks are drawn in the color of the rating. The Enhanced Fujita scale rates the damage rather than measuring the wind: the speeds are what that damage is taken to imply.

  1. EF065 to 85 mphthis tornado

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

  2. EF186 to 110 mph

    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.

The record

Rating
EF0
Date
September 6, 2007
Touchdown
5:20 AM CDT (10:20 UTC)
Path length
0.5 miles (0.8 km)
Path width
50 yards (46 m)
Deaths
0
Injuries
0
Property damage
$2,000
County
Christian County
Touchdown point
37.030, -93.470
Lift-off point
37.030, -93.470
Record number
0709060420-01

What the Weather Service recorded

Early morning thunderstorms produced flash flooding in several counties in southwest Missouri. One thunderstorm produced a weak EF-0 tornado in the community of Clever.

A National Weather Service storm survey revealed that an EF-0 tornado briefly touched down in Clever. The tornado caused minor damage to a bank along with surrounding trees and outdoor lawn furniture.

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

The warnings

No tornado warning for this county appears in the archive as in force at the moment the tornado touched down.

Issued (UTC)ExpiredProductOffice
09:48 UTC13:00 UTCFlood AdvisorySGF
10:35 UTC17:00 UTCFlash Flood WarningSGF
17:43 UTC21:00 UTCFlash Flood WarningSGF
20:48 UTC01:00 UTCFlood WarningSGF

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 forecast that day

The Storm Prediction Center had this point in a General Thunderstorms Risk, with a 0.02 chance of a tornado within 25 miles. The outlook in force was issued at 06:05 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 air that afternoon

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.

Springfield, MO (KSGF), 00:00Z

10.3 hours before the tornado, 33 km from the path. September 6, 2007.

Skew-T log-pSkew-T log-p diagram, Springfield, MO at 00:00Z on 2007-09-06Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 208 joules per kilogram, CIN -5, lifted condensation level 644 meters above ground. Wind barbs in knots down the right edge.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed. The warm shading is its CAPE, the cool shading the inhibition it has to break through.
HodographHodograph, Springfield, MO at 00:00Z on 2007-09-06The wind through the lowest 10 kilometers as a curve, rings every 10 meters per second labeled in knots. Zero to 1 km storm-relative helicity 74 square meters per square second, 0 to 6 km bulk shear 12 knots.193958Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km. RM and LM are the right and left moving storms Bunkers' method gives; the shaded area is the 0 to 1 km storm-relative helicity.
Mixed-layer CAPE
208 J/kg
Mixed-layer CIN
-5 J/kg
Surface CAPE
456 J/kg
Mixed-layer LCL
644 m above ground
0-6 km bulk shear
12 kt
0-1 km bulk shear
20 kt
0-1 km storm-relative helicity
74 m²/s²
0-3 km storm-relative helicity
85 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0
0-3 km lapse rate
5.6 K/km

Open this sounding in Storm Lab

Springfield, MO (KSGF), 12:00Z

1.7 hours after it, 33 km from the path. September 6, 2007.

Skew-T log-pSkew-T log-p diagram, Springfield, MO at 12:00Z on 2007-09-06Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 780 joules per kilogram, CIN -17, lifted condensation level 495 meters above ground. Wind barbs in knots down the right edge.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed. The warm shading is its CAPE, the cool shading the inhibition it has to break through.
HodographHodograph, Springfield, MO at 12:00Z on 2007-09-06The wind through the lowest 10 kilometers as a curve, rings every 10 meters per second labeled in knots. Zero to 1 km storm-relative helicity 0 square meters per square second, 0 to 6 km bulk shear 0 knots.1939Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km. RM and LM are the right and left moving storms Bunkers' method gives; the shaded area is the 0 to 1 km storm-relative helicity.
Mixed-layer CAPE
780 J/kg
Mixed-layer CIN
-17 J/kg
Surface CAPE
106 J/kg
Mixed-layer LCL
495 m above ground
0-6 km bulk shear
0 kt
0-1 km bulk shear
0 kt
0-1 km storm-relative helicity
0 m²/s²
0-3 km storm-relative helicity
0 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0
0-3 km lapse rate
4.8 K/km

Open this sounding in Storm Lab

The surface observations

Springfield (SGF), 24 km from the path, in the two hours either side.

Time (UTC)Temp (°F)Dew point (°F)WindGust (kt)Pressure (mb)Weather
08:27 UTC69.868170° 8 kt1013.5RA BR
08:47 UTC69.868160° 7 kt1013.2-RA
08:52 UTC7068160° 7 kt1013.2
09:18 UTC69.868160° 6 kt1013.2-RA
09:25 UTC69.869.8170° 9 kt1013.5VCTS RA BR
09:31 UTC69.868170° 10 kt1013.2VCTS +RA BR
09:34 UTC69.868160° 9 kt161013.2VCTS +RA BR
09:41 UTC69.868180° 7 kt1013.5VCTS +RA BR
09:47 UTC69.869.8180° 7 kt1013.5TSRA BR
09:52 UTC7069210° 9 kt1013.5+TSRA BR
09:59 UTC69.868220° 12 kt191013.9+TSRA BR
10:08 UTC66.266.2190° 6 kt1013.5+TSRA BR
10:38 UTC66.266.2120° 10 kt1013.5+TSRA BR
10:47 UTC66.264.4100° 5 kt1013.5-TSRA
10:52 UTC6766120° 5 kt1013.5TS
11:16 UTC6866.20° 0 kt1013.9
11:22 UTC6866.2360° 4 kt1013.9
11:52 UTC6966140° 3 kt1014.2

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

The radar

The Springfield radar (KSGF), 24 km away, was scanning. The volume nearest the touchdown began at 10:21 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.

What was reported nearby

Local storm reports within 60 km of the path, in the three hours either side.

Time (UTC)ReportWhereCountyRemark
10:13 UTCTSTM WND DMGBillingsChristian, MOTREE LIMBS DOWN AND POWER OUTAGES
10:13 UTCTSTM WND DMGCleverChristian, MOCHRISTIAN COUNTY EMERGENCY MANAGEMENT REPORTED DAMAGE TO THE ROOF OF A BANK ALONG WITH TREE LIMBS DOWN. POWER OUTAGES ALSO REPORTED.
10:13 UTCTSTM WND DMGCleverChristian, MOTREE LIMBS DOWN AND POWER OUTAGES REPORTED
10:20 UTCTORNADOCleverChristian, MOEF-0 TORNADO CONFIRMED IN CLEVER. TRACK WAS 0.5 MILES LONG AND 50 YARDS WIDE WITH DAMAGE TO A BANK...TREES AND OUTDOOR FURNISHING. TORNADO LIFTED NEAR INTERSECTION OF HIGHWAYS P AND 14.
10:31 UTCFLASH FLOODSpringfieldGreene, MOWATER RUNNING OVER HIGHWAY 164 BETWEEN GOLDEN AND SUNRISE.
10:32 UTCFLASH FLOODSpringfieldGreene, MOWATER UP TO A FOOT DEEP AT INTERSECTION OF CAMPBELL AND MADISON.
11:30 UTCFLASH FLOODSpringfieldGreene, MOSEVERAL INCHES OF FLOWING WATER ACROSS BUENA VISTA ROAD AT WARD BRANCH.

From the Iowa Environmental Mesonet's archive of National Weather Service local storm reports.

This ground now

The live radar over the trackEvery 2007 tornado in MissouriEvery tornado in Missouri since 1950Warnings in force in Missouri nowThe forecast where you are

The other tornadoes of September 6, 2007

4 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
September 62:15 PM CDTEF0Jersey, IL0.950
September 61:45 PM MDTEF0Grant, NM3.040
September 65:27 PM CDTEF0Dodge, NE3.250
September 66:28 PM CDTEF0Sangamon, IL0.110

What this means

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.

Sources

NOAA Storm Prediction Center tornado database, 1950-2025, the official record kept by NOAA's Storm Prediction Center.