Tornadoes · United States · Missouri · 2006

F0 tornado, Alton, Missouri, May 3, 2006

This F0 tornado ran 2.0 miles across Oregon County on May 3, 2006, touching down at 1:57 PM CDT and reaching 20 yards wide. It killed nobody.

The rating scale

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

  1. F040 to 72 mphthis tornado

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

  2. F173 to 112 mph

    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.

The record

Rating
F0
Date
May 3, 2006
Touchdown
1:57 PM CDT (18:57 UTC)
Path length
2.0 miles (3.2 km)
Path width
20 yards (18 m)
Deaths
0
Injuries
0
County
Oregon County
Touchdown point
36.620, -91.170
Lift-off point
36.620, -91.130
Record number
459

What the Weather Service recorded

A National Weather Service storm survey revealed that a weak tornado tracked through a highly remote and wooded area of eastern Oregon County. The tornado initially touched down three miles east of Riverton near County Road 152 just north of Highway 160, and moved two miles east. Intermitten minor tree damage was found along the 20 yard wide path.

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

The warnings

17 minutes of warning. NWS SGF issued a tornado warning for this county at 18:40 UTC, 17 minutes before the tornado touched down, in force until 19:45 UTC.

The county was under a severe thunderstorm watch, issued at 18:05 UTC and running to 00:48 UTC.

Issued (UTC)ExpiredProductOffice
17:57 UTC19:00 UTCSevere Thunderstorm WarningSGF
18:05 UTC00:48 UTCSevere Thunderstorm WatchSGF
18:40 UTC19:45 UTCTornado WarningSGF
19:15 UTC01:15 UTCFlash Flood WarningSGF
00:48 UTC04:55 UTCSevere Thunderstorm WatchSGF
03:30 UTC04:15 UTCSevere Thunderstorm 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 Slight Risk, with a 0.02 chance of a tornado within 25 miles. The outlook in force was issued at 16:21 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 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.

Little Rock, AR (KLZK), 12:00Z

7.0 hours before the tornado, 227 km from the path. May 3, 2006.

Skew-T log-pSkew-T log-p diagram, Little Rock, AR at 12:00Z on 2006-05-03Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 1440 joules per kilogram, CIN -68, lifted condensation level 852 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, Little Rock, AR at 12:00Z on 2006-05-03The 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 -52 square meters per square second, 0 to 6 km bulk shear 8 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
1440 J/kg
Mixed-layer CIN
-68 J/kg
Surface CAPE
745 J/kg
Mixed-layer LCL
852 m above ground
0-6 km bulk shear
8 kt
0-1 km bulk shear
18 kt
0-1 km storm-relative helicity
-52 m²/s²
0-3 km storm-relative helicity
-4 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

Little Rock, AR (KLZK), 00:00Z

5.0 hours after it, 227 km from the path. May 4, 2006.

Skew-T log-pSkew-T log-p diagram, Little Rock, AR at 00:00Z on 2006-05-04Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 1667 joules per kilogram, CIN -5, lifted condensation level 1142 meters above ground. Wind barbs in knots down the right edge.LCLEL10008507005003002001001 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, Little Rock, AR at 00:00Z on 2006-05-04The 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 42 square meters per square second, 0 to 6 km bulk shear 24 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
1667 J/kg
Mixed-layer CIN
-5 J/kg
Surface CAPE
1848 J/kg
Mixed-layer LCL
1142 m above ground
0-6 km bulk shear
24 kt
0-1 km bulk shear
10 kt
0-1 km storm-relative helicity
42 m²/s²
0-3 km storm-relative helicity
137 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.3
0-3 km lapse rate
7.4 K/km

Open this sounding in Storm Lab

The radar

The Memphis radar (KNQA), 182 km away, was scanning. The volume nearest the touchdown began at 18:58 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
18:57 UTCTORNADO 014 Ese AltonOregon, MOF0 TORNADO LOCATED BY NWS STORM SURVEY. TRACK BEGAN THREE MILES EAST OF RIVERTON NEAR COUNTY ROAD 152 JUST NORTH OF HIGHWAY 160 AND MOVED TWO MILES EAST. INTERMITTENT MINOR TREE DAMAGE WAS FOUND ALONG THE 20 YARD WIDE PA
19:20 UTCHAIL 2.7510 E AltonOregon, MO
19:54 UTCHAIL 1HandyRipley, MO
20:22 UTCFUNNEL CLOUD10 W Poplar BluffButler, MONEAR STRINGTOWN
21:32 UTCHAIL 1DoniphanRipley, MOHAIL MOSTLY 3/4 INCH BUT SOME UPTO 1 INCH IN SIZE

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

This ground now

The live radar over the trackEvery 2006 tornado in MissouriEvery tornado in Missouri since 1950Warnings in force in Missouri nowThe forecast where you are

The other tornadoes of May 3, 2006

4 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
May 33:53 PM CDTF0Bourbon, KS to MO11.050
May 36:09 PM CDTF0Crawford, KS0.130
May 36:25 PM CDTF0Barton, MO16.050
May 37:56 PM CDTF0Dade, MO8.025

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.