Tornadoes · United States · Missouri · 2011

EF1 tornado, Neelyville, Missouri, April 23, 2011

This EF1 tornado ran 3.0 miles across Butler County on April 23, 2011, touching down at 12:02 AM CDT and reaching 100 yards wide. It killed nobody, and did $175,000 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 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.

The record

Rating
EF1
Date
April 23, 2011
Touchdown
12:02 AM CDT (05:02 UTC)
Lifted
12:05 AM CDT (05:05 UTC)
On the ground
3 minutes
Path length
3.0 miles (4.8 km)
Path width
100 yards (91 m)
Deaths
0
Injuries
0
Property damage
$175,000
County
Butler County
Touchdown point
36.550, -90.526
Lift-off point
36.580, -90.487
Record number
1104232302-01

What the Weather Service recorded

Bands of thunderstorms developed along a surface cold front extending from northern Arkansas northeastward along the Ohio River. Relatively strong diurnal heating occurred south of the front, where mixed-layer cape values increased to around 1500 j/kg. Steep mid-level lapse rates and rather strong deep-layer wind shear promoted a few supercell structures within these bands of storms.

The intermittent damage path began along U.S. Highway 67 south-southwest of Neelyville. The damage along U.S. Highway 67 south of town was minor roofing and siding damage to eight structures. A bank window was blown out. The tornado was rated EF-0 in this area. The tornado then increased to EF-1 northeast of Neelyville, where two mobile homes were destroyed and six others were damaged. Peak winds were estimated near 90 mph.

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
17:56 UTC21:00 UTCFlood AdvisoryPAH
22:13 UTC02:00 UTCFlood AdvisoryPAH
22:46 UTC05:00 UTCSevere Thunderstorm WatchPAH
01:25 UTC13:15 UTCFlash Flood WarningPAH
01:35 UTC02:00 UTCSevere Thunderstorm WarningPAH
02:15 UTC02:31 UTCFlood WarningPAH
04:57 UTC05:30 UTCSevere Thunderstorm WarningPAH
17:02 UTC03:00 UTCFlood WarningPAH
18:56 UTC21:45 UTCFlash Flood WarningPAH

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 00:56 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), 00:00Z

5.0 hours before the tornado, 199 km from the path. April 24, 2011.

Skew-T log-pSkew-T log-p diagram, Little Rock, AR at 00:00Z on 2011-04-24Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 781 joules per kilogram, CIN -114, lifted condensation level 1432 meters above ground. Wind barbs in knots down the right edge.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°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 2011-04-24The 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 166 square meters per square second, 0 to 6 km bulk shear 42 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
781 J/kg
Mixed-layer CIN
-114 J/kg
Surface CAPE
1289 J/kg
Mixed-layer LCL
1432 m above ground
0-6 km bulk shear
42 kt
0-1 km bulk shear
22 kt
0-1 km storm-relative helicity
166 m²/s²
0-3 km storm-relative helicity
226 m²/s²
Significant tornado parameter
0.3
Supercell composite
5.7
0-3 km lapse rate
6.4 K/km

Open this sounding in Storm Lab

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

7.0 hours after it, 199 km from the path. April 24, 2011.

Skew-T log-pSkew-T log-p diagram, Little Rock, AR at 12:00Z on 2011-04-24Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 1899 joules per kilogram, CIN -57, lifted condensation level 664 meters above ground. Wind barbs in knots down the right edge.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°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 2011-04-24The 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 189 square meters per square second, 0 to 6 km bulk shear 47 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
1899 J/kg
Mixed-layer CIN
-57 J/kg
Surface CAPE
653 J/kg
Mixed-layer LCL
664 m above ground
0-6 km bulk shear
47 kt
0-1 km bulk shear
30 kt
0-1 km storm-relative helicity
189 m²/s²
0-3 km storm-relative helicity
23 m²/s²
Significant tornado parameter
0.3
Supercell composite
2.0
0-3 km lapse rate
5.1 K/km

Open this sounding in Storm Lab

The surface observations

Corning (4M9), 22 km from the path, in the two hours either side.

Time (UTC)Temp (°F)Dew point (°F)WindGust (kt)Pressure (mb)Weather
03:15 UTC6866.2340° 7 kt141014.2+TSRA
03:35 UTC66.264.4110° 7 kt1013.9+TSRA
03:55 UTC66.264.4170° 12 kt1012.5TSBR
04:15 UTC66.266.210° 5 kt1012.9TSRA
04:35 UTC6866.2120° 6 kt1012.2VCTS -RA
04:55 UTC6864.4310° 21 kt271013.9TS
05:35 UTC66.264.4130° 9 kt1012.5VCTS
05:55 UTC66.264.4140° 11 kt1012.5
06:15 UTC6864.4140° 13 kt1012.5VCTS
06:35 UTC6864.4140° 11 kt1012.5
06:55 UTC6864.4140° 11 kt1012.5

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

The radar

The Memphis radar (KNQA), 147 km away, was scanning. The volume nearest the touchdown began at 05:02 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
04:37 UTCFLASH FLOODPoplar BluffButler, MO4 WATER RESCUES...FROM HOMES AND CARS...5 INTERSECTIONS CLOSED. WATER BEING PUMPED.
05:20 UTCTSTM WND DMGNeelyvilleButler, MOPOWER LINES DOWN AND ELECTRICITY OUT IN THE TOWN.
05:20 UTCTORNADO1 Wsw NeelyvilleButler, MO...LATE REPORT...EF-1 TORNADO OCCURRED ALONG U.S. HIGHWAY 67. PATH LENGTH 0.6 MILES. TWO MOBILE HOMES DESTROYED.

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

This ground now

The live radar over the trackEvery 2011 tornado in MissouriEvery tornado in Missouri since 1950Warnings in force in Missouri nowThe forecast where you are

The other tornadoes of April 23, 2011

11 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
April 236:09 AM EDTEF0Harrison, KY0.575
April 231:31 PM CDTEF0Stoddard, MO0.580$50,000
April 232:59 PM EDTEF0Grant, KY1.125$25,000
April 233:10 PM EDTEF1Grant, KY4.350$35,000
April 233:14 PM EDTEF1Kenton, KY0.250$15,000
April 232:15 PM CDTEF2Alexander, IL2.9175$700,000
April 232:29 PM CDTEF1Ballard, KY1.680$100,000
April 232:30 PM CDTEF2Carlisle, KY4.04502$2.0 million
April 232:47 PM CDTEF1Massac, IL6.6250$450,000
April 237:58 PM CDTEF1Madison, AR28.3880$500,000
April 238:13 PM CDTEF0Comanche, TX0.030

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.