Tornadoes · United States · Oklahoma · 2013

EF0 tornado, LeFlore County, Oklahoma, May 20, 2013

This EF0 tornado ran 0.7 miles across LeFlore County on May 20, 2013, touching down at 8:33 PM CDT and reaching 260 yards wide. It killed nobody.

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
May 20, 2013
Touchdown
8:33 PM CDT (01:33 UTC)
Lifted
8:34 PM CDT (01:34 UTC)
On the ground
1 minutes
Path length
0.7 miles (1.1 km)
Path width
260 yards (238 m)
Deaths
0
Injuries
0
County
LeFlore County
Touchdown point
35.140, -94.876
Lift-off point
35.145, -94.863
Record number
1305201933-01

The warnings

3 minutes of warning. NWS TSA issued a tornado warning for this county at 01:30 UTC, 3 minutes before the tornado touched down, in force until 02:30 UTC.

The county was under a tornado watch, issued at 00:49 UTC and running to 05:03 UTC.

Issued (UTC)ExpiredProductOffice
18:10 UTC00:49 UTCTornado WatchTSA
23:55 UTC01:00 UTCSevere Thunderstorm WarningTSA
23:59 UTC01:00 UTCSevere Thunderstorm WarningTSA
00:00 UTC00:00 UTCFlash Flood WatchTSA
00:23 UTC00:45 UTCSevere Thunderstorm WarningTSA
00:49 UTC05:03 UTCTornado WatchTSA
00:50 UTC02:00 UTCSevere Thunderstorm WarningTSA
01:02 UTC02:00 UTCSevere Thunderstorm WarningTSA
01:18 UTC02:15 UTCSevere Thunderstorm WarningTSA
01:30 UTC02:30 UTCTornado WarningTSA
01:52 UTC02:30 UTCTornado WarningTSA
01:57 UTC02:44 UTCSevere Thunderstorm WarningTSA
04:56 UTC05:30 UTCSevere Thunderstorm WarningTSA
05:03 UTC12:00 UTCSevere Thunderstorm WatchTSA
11:44 UTC17:30 UTCFlash Flood WarningTSA
13:55 UTC18:00 UTCFlash Flood WarningTSA
15:46 UTC21:32 UTCSevere Thunderstorm WatchTSA
17:15 UTC23:00 UTCFlash Flood WarningTSA
17:19 UTC23:30 UTCFlash Flood WarningTSA

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 01:00 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

1.6 hours before the tornado, 218 km from the path. May 21, 2013.

Skew-T log-pSkew-T log-p diagram, Springfield, MO at 00:00Z on 2013-05-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 2135 joules per kilogram, CIN -10, lifted condensation level 780 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, Springfield, MO at 00:00Z on 2013-05-21The 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 236 square meters per square second, 0 to 6 km bulk shear 49 knots.19395878Sfc1 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
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

Open this sounding in Storm Lab

Springfield, MO (KSGF), 12:00Z

10.4 hours after it, 218 km from the path. May 21, 2013.

Skew-T log-pSkew-T log-p diagram, Springfield, MO at 12:00Z on 2013-05-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 22 joules per kilogram, CIN -222, lifted condensation level 1272 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, Springfield, MO at 12:00Z on 2013-05-21The 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 122 square meters per square second, 0 to 6 km bulk shear 51 knots.19395878Sfc1 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
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

Open this sounding in Storm Lab

The radar

The Western Arkansas radar (KSRX), 49 km away, was scanning. The volume nearest the touchdown began at 01:32 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
00:21 UTCTSTM WND DMGVianSequoyah, OKTREES DOWN ON HOMES AND VEHICLES IN TOWN.
01:14 UTCTSTM WND DMGTalihinaLe Flore, OKTREES AND POWERLINES DOWN IN TOWN.
01:32 UTCTORNADO5 Wsw BokosheLe Flore, OKREPORT FROM LAW ENFORCEMENT RADIO OF A TORNADO BETWEEN MCCURTAIN AND BOKOSHE COLOCATED WITH A STRONG RADAR CIRCULATION. BROADCAST MEDIA REPORTED POWER FLASHES IN THE AREA. EMERGENCY MANAGEMENT REPORTED TREE DAMAGE. TIME
01:41 UTCTSTM WND DMG12 Sw ShortSequoyah, OKTREE DOWN ALONG HIGHWAY 101.
01:41 UTCTSTM WND DMGPoteauLe Flore, OKBUILDING DOWNTOWN WITH ITS ROOF BLOWN OFF. NUMEROUS BUILDINGS HAVE WINDOWS BLOWN OUT. NUMEROUS TREES AND POWER LINES DOWN.
01:41 UTCTSTM WND GST 60PoteauLe Flore, OKSUSTAINED 55 TO 60 MPH WINDS
01:46 UTCTORNADO3 Ne PoteauLe Flore, OKNWS SURVEY INDICATED A EF-0 OCCURRED BETWEEN POTEAU AND CAMERON. TIME ESTIMATED BY RADAR. ADDITIONAL INFORMATION TO BE DETERMINED.
01:50 UTCTORNADOCameronLe Flore, OKLAW ENFORCEMENT RADIO REPORTED A TORNADO NEAR CAMERON COLOCATED WITH A STRONG RADAR CIRCULATION. IT MAY HAVE CONTINUED TO THE ROCK ISLAND VICINITY. EMERGENCY MANAGEMENT REPORTS POWER LINES DOWN IN CAMERON. DAMAGE TO A SI
02:08 UTCTSTM WND DMGArkomaLe Flore, OK12 INCH TREE LIMBS DOWNED.

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 OklahomaEvery tornado in Oklahoma since 1950Warnings in force in Oklahoma nowThe forecast where you are

The other tornadoes of May 20, 2013

35 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
May 202:56 PM CDTEF5Moore tornado, OK13.81,90024212$2.0 billion
May 202:58 PM CDTEF0Stephens, OK1.030
May 203:07 PM CDTEF1Stephens, OK4.0200$20,000
May 203:51 PM CDTEF1Washington, OK6.5500$5,000
May 204:12 PM CDTEF0Montgomery, KS0.550
May 204:21 PM CDTEF1Washington, OK4.5400$10,000
May 204:33 PM CDTEF1Washington, OK6.0500$30,000
May 204:35 PM CDTEF0Brown, TX1.250
May 204:40 PM CDTEF0Lincoln, OK1.2100
May 204:50 PM CDTEF0Stanton, KS0.450
May 204:57 PM CDTEF1Pettis, MO14.5200$20,000
May 205:05 PM CDTEF0Stanton, KS0.350
May 205:37 PM CDTEF0Cedar, MO3.2100$50,000
May 205:41 PM CDTEF0Montague, TX0.950
May 205:41 PM CDTEF1Brown, TX3.6350$100,000
May 204:53 PM MDTEF0Alamosa, CO0.175
May 206:00 PM CDTEF0Brown, TX0.250
May 206:03 PM CDTEF1Barton, MO6.8100$50,000
May 206:25 PM CDTEF2Ottawa, OK10.0800$1.0 million
May 206:32 PM CDTEF1Adair, OK to MO2.0150
May 206:32 PM CDTEF1Ottawa, OK to MO9.3600$250,000
May 206:35 PM CDTEF1Adair, OK2.5300$15,000
May 206:40 PM CDTEF1Adair, OK to AR8.0500$225,000
May 206:49 PM CDTEF1Benton, AR2.9500$50,000
May 206:49 PM CDTEF1Coal, OK5.9250$30,000
May 206:56 PM CDTEF0St. Clair, MO0.5200
May 207:24 PM CDTEF1Benton, AR0.8270$50,000
May 207:24 PM CDTEF1Marion, MO1.250
May 207:25 PM CDTEF0Mills, TX1.1100
May 207:50 PM CDTEF1Stone, MO1.4200$50,000
May 208:05 PM CDTEF0Stone, MO0.6100
May 208:05 PM CDTEF1Stone, MO1.4100
May 208:44 PM CDTEF1LeFlore, OK8.5500$5,000
May 208:46 PM CDTEF0Morgan, MO0.7100$50,000
May 2010:14 PM CDTEF2Macoupin, IL0.2753

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.