Tornadoes · United States · Missouri · 2013
EF1 tornado, Shell Knob to Tauria, Missouri, May 20, 2013
From Shell Knob to Tauria, this EF1 tornado ran 1.4 miles across Stone and Barry counties on May 20, 2013, touching down at 7:50 PM CDT and reaching 200 yards wide. It killed nobody, and did $50,000 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.
EF065 to 85 mph
Light damage. Surface peeled off some roofs, gutters and siding damaged, branches broken, shallow-rooted trees pushed over.
EF186 to 110 mphthis tornado
Moderate damage. Roofs badly stripped, mobile homes overturned or badly damaged, exterior doors lost, windows broken.
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.
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.
EF4166 to 200 mph
Devastating damage. Well-built houses leveled, structures with weak foundations moved some distance, cars thrown and large missiles generated.
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.
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
- May 20, 2013
- Touchdown
- 7:50 PM CDT (00:50 UTC)
- Lifted
- 7:52 PM CDT (00:52 UTC)
- On the ground
- 2 minutes
- Path length
- 1.4 miles (2.3 km)
- Path width
- 200 yards (183 m)
- Deaths
- 0
- Injuries
- 0
- Property damage
- $50,000
- Counties
- Stone and Barry counties
- Touchdown point
- 36.628, -93.585
- Lift-off point
- 36.642, -93.567
- Record number
- 1305201850-01
What the Weather Service recorded
A strong negatively titled upper level trough developed over the central portions of the country. A slow moving cold front moved into the Missouri Ozarks. This setup caused for several rounds of severe and slow moving thunderstorms which lead to widespread wind damage, large hail, and several low end tornadoes along with isolated flooding due to heavy rainfall.
An EF-0 tornado uprooted and damaged trees along its path. Winds were estimated around 110 mph. This tornado continued into Stone County.
An EF-0 tornado continued from Barry County into Stone County uprooting and damaging trees. Winds were estimated on the Stone County side of the track around 80 mph.
An EF-1 tornado uprooted trees along its path. Estimated winds were around 90 mph.
An EF-0 tornado caused some tree damage along its path. Winds were estimated around 80 mph.
From NOAA NCEI's Storm Events Database, the narrative the local forecast office wrote for Storm Data.
The warnings
23 minutes of warning. NWS SGF issued a tornado warning for this county at 00:27 UTC, 23 minutes before the tornado touched down, in force until 01:00 UTC.
The county was under a tornado watch, issued at 17:49 UTC and running to 00:56 UTC.
| Issued (UTC) | Expired | Product | Office |
|---|---|---|---|
| 17:49 UTC | 00:56 UTC | Tornado Watch | SGF |
| 00:27 UTC | 01:00 UTC | Tornado Warning | SGF |
| 00:56 UTC | 01:37 UTC | Tornado Watch | SGF |
| 01:00 UTC | 08:32 UTC | Flash Flood Watch | SGF |
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 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 19:58 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
0.8 hours before the tornado, 36 km from the path. May 21, 2013.
- Mixed-layer CAPE
- 2135 J/kg
- Mixed-layer CIN
- -10 J/kg
- Surface CAPE
- 2535 J/kg
- Mixed-layer LCL
- 780 m above ground
- 0-6 km bulk shear
- 49 kt
- 0-1 km bulk shear
- 31 kt
- 0-1 km storm-relative helicity
- 236 m²/s²
- 0-3 km storm-relative helicity
- 265 m²/s²
- Significant tornado parameter
- 3.2
- Supercell composite
- 13.9
- 0-3 km lapse rate
- 5.7 K/km
Springfield, MO (KSGF), 12:00Z
11.2 hours after it, 36 km from the path. May 21, 2013.
- Mixed-layer CAPE
- 22 J/kg
- Mixed-layer CIN
- -222 J/kg
- Surface CAPE
- 0 J/kg
- Mixed-layer LCL
- 1272 m above ground
- 0-6 km bulk shear
- 51 kt
- 0-1 km bulk shear
- 15 kt
- 0-1 km storm-relative helicity
- 122 m²/s²
- 0-3 km storm-relative helicity
- 130 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.2
- 0-3 km lapse rate
- 4.5 K/km
The surface observations
Branson (BBG), 35 km from the path, in the two hours either side.
| Time (UTC) | Temp (°F) | Dew point (°F) | Wind | Gust (kt) | Pressure (mb) | Weather |
|---|---|---|---|---|---|---|
| 23:45 UTC | 77 | 68 | 160° 6 kt | 1007.8 | ||
| 00:45 UTC | 75.2 | 68 | 160° 8 kt | 1007.8 | ||
| 01:45 UTC | 62.6 | 57.2 | 220° 5 kt | 1008.8 | -TSRA | |
| 02:15 UTC | 62.6 | 59 | 260° 8 kt | 1010.5 | -TSRA | |
| 02:35 UTC | 62.6 | 59 | 190° 13 kt | 23 | 1010.2 | -TSRA |
From the Iowa Environmental Mesonet's archive of airport observations.
The radar
The Springfield radar (KSGF), 69 km away, was scanning. The volume nearest the touchdown began at 00:50 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) | Report | Where | County | Remark |
|---|---|---|---|---|
| 23:24 UTC | HAIL 0.5 | 2 N Purdy | Barry, MO | DIME SIZE |
| 23:53 UTC | HAIL 1.5 | Aurora | Lawrence, MO | PICTURE FROM SOCIAL MEDIA. TIME WAS ESTIMATED. |
| 23:55 UTC | TSTM WND DMG | Blue Eye | Carroll, AR | TREES DOWN AND POWER OUTAGES IN AND AROUND THE VICINITY OF BLUE EYE. |
| 23:57 UTC | HAIL 1 | Marionville | Lawrence, MO | TIME OF EVENT ESTIMATED. |
| 00:15 UTC | TSTM WND DMG | Battlefield | Greene, MO | PICTURE FROM SOCIAL MEDIA OF A TREE SNAP AND FELL ON AN OUT BUILDING. TIME WAS ESTIMATED. |
| 00:50 UTC | TSTM WND DMG | 6 S Springfield | Greene, MO | DELAYED REPORT OF A TREE DOWN NEAR CAMPBELL ROAD AND NOTTINGHAM ROAD. |
| 00:50 UTC | TORNADO | 3 E Shell Knob | Barry, MO | AN EF-1 TORNADO UPROOTED AND DAMAGED TREES ALONG ITS 1.4 MILE LONG PATH WITH MAXIMUM WINDS OF 110 MPH AND PATH WIDTH OF 200 YARDS. |
| 00:59 UTC | TSTM WND GST 60 | Branson West | Stone, MO | |
| 01:05 UTC | TSTM WND DMG | Reeds Spring | Stone, MO | NUMEROUS TREES REPORTED DOWN IN AND NEAR REEDS SPRING. TREES ALSO REPORTED DOWN ALONG HIGHWAY 413. |
| 01:05 UTC | TORNADO | 2 N Reeds Spring | Stone, MO | AN EF-0 TORNADO 100 YARDS WIDE AND 0.6 MILES LONG CAUSED SOME TREE DAMAGE ALONG ITS PATH. ESTIMATED WIND SPEEDS WERE 80 TO 85 MPH. |
| 01:05 UTC | TORNADO | 3 Nnw Reeds Spring | Stone, MO | AN EF-1 TORNADO 100 YARDS WIDE AND 1.4 MILES LONG UPROOTED TREES ALONG ITS PATH. ESTIMATED WIND SPEEDS WERE AROUND 90 MPH. |
| 01:10 UTC | TSTM WND DMG | Branson | Taney, MO | WIND DAMAGE TO SHINGLES AND SIDING TO A COUPLE OF HOTELS ON WEST SIDE OF BRANSON. |
| 01:10 UTC | TSTM WND GST 65 | 2 N Branson | Taney, MO | POWER OUTAGES REPORTED AT HIGHWAY F AND 65 NORTH OF BRANSON. |
| 01:20 UTC | TSTM WND DMG | Taneyville | Taney, MO | HAYBARN DESTROYED. TIME OF EVENT ESTIMATED. |
| 01:31 UTC | TSTM WND DMG | Forsyth | Taney, MO | TWO MOBIL HOMES EPORTED DAMAGED FROM FALLEN TREES. |
From the Iowa Environmental Mesonet's archive of National Weather Service local storm reports.
This ground now
The live radar over the trackEvery 2013 tornado in MissouriEvery tornado in Missouri since 1950Warnings in force in Missouri nowThe forecast where you are
The other tornadoes of May 20, 2013
35 more were confirmed in the United States that day.
| Date | Time | Rating | Where | Path (mi) | Width (yd) | Deaths | Injuries | Damage |
|---|---|---|---|---|---|---|---|---|
| May 20 | 2:56 PM CDT | EF5 | Moore tornado, OK | 13.8 | 1,900 | 24 | 212 | $2.0 billion |
| May 20 | 2:58 PM CDT | EF0 | Stephens, OK | 1.0 | 30 | |||
| May 20 | 3:07 PM CDT | EF1 | Stephens, OK | 4.0 | 200 | $20,000 | ||
| May 20 | 3:51 PM CDT | EF1 | Washington, OK | 6.5 | 500 | $5,000 | ||
| May 20 | 4:12 PM CDT | EF0 | Montgomery, KS | 0.5 | 50 | |||
| May 20 | 4:21 PM CDT | EF1 | Washington, OK | 4.5 | 400 | $10,000 | ||
| May 20 | 4:33 PM CDT | EF1 | Washington, OK | 6.0 | 500 | $30,000 | ||
| May 20 | 4:35 PM CDT | EF0 | Brown, TX | 1.2 | 50 | |||
| May 20 | 4:40 PM CDT | EF0 | Lincoln, OK | 1.2 | 100 | |||
| May 20 | 4:50 PM CDT | EF0 | Stanton, KS | 0.4 | 50 | |||
| May 20 | 4:57 PM CDT | EF1 | Pettis, MO | 14.5 | 200 | $20,000 | ||
| May 20 | 5:05 PM CDT | EF0 | Stanton, KS | 0.3 | 50 | |||
| May 20 | 5:37 PM CDT | EF0 | Cedar, MO | 3.2 | 100 | $50,000 | ||
| May 20 | 5:41 PM CDT | EF0 | Montague, TX | 0.9 | 50 | |||
| May 20 | 5:41 PM CDT | EF1 | Brown, TX | 3.6 | 350 | $100,000 | ||
| May 20 | 4:53 PM MDT | EF0 | Alamosa, CO | 0.1 | 75 | |||
| May 20 | 6:00 PM CDT | EF0 | Brown, TX | 0.2 | 50 | |||
| May 20 | 6:03 PM CDT | EF1 | Barton, MO | 6.8 | 100 | $50,000 | ||
| May 20 | 6:25 PM CDT | EF2 | Ottawa, OK | 10.0 | 800 | $1.0 million | ||
| May 20 | 6:32 PM CDT | EF1 | Adair, OK to MO | 2.0 | 150 | |||
| May 20 | 6:32 PM CDT | EF1 | Ottawa, OK to MO | 9.3 | 600 | $250,000 | ||
| May 20 | 6:35 PM CDT | EF1 | Adair, OK | 2.5 | 300 | $15,000 | ||
| May 20 | 6:40 PM CDT | EF1 | Adair, OK to AR | 8.0 | 500 | $225,000 | ||
| May 20 | 6:49 PM CDT | EF1 | Benton, AR | 2.9 | 500 | $50,000 | ||
| May 20 | 6:49 PM CDT | EF1 | Coal, OK | 5.9 | 250 | $30,000 | ||
| May 20 | 6:56 PM CDT | EF0 | St. Clair, MO | 0.5 | 200 | |||
| May 20 | 7:24 PM CDT | EF1 | Benton, AR | 0.8 | 270 | $50,000 | ||
| May 20 | 7:24 PM CDT | EF1 | Marion, MO | 1.2 | 50 | |||
| May 20 | 7:25 PM CDT | EF0 | Mills, TX | 1.1 | 100 | |||
| May 20 | 8:05 PM CDT | EF0 | Stone, MO | 0.6 | 100 | |||
| May 20 | 8:05 PM CDT | EF1 | Stone, MO | 1.4 | 100 | |||
| May 20 | 8:33 PM CDT | EF0 | LeFlore, OK | 0.7 | 260 | |||
| May 20 | 8:44 PM CDT | EF1 | LeFlore, OK | 8.5 | 500 | $5,000 | ||
| May 20 | 8:46 PM CDT | EF0 | Morgan, MO | 0.7 | 100 | $50,000 | ||
| May 20 | 10:14 PM CDT | EF2 | Macoupin, IL | 0.2 | 75 | 3 |
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.