Tornadoes · United States · Oklahoma · 2016

Unrated tornado, Selman, Oklahoma, May 23, 2016

This Unrated tornado ran 2.0 miles across Harper County on May 23, 2016, touching down at 9:24 PM CDT and reaching 50 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 mph

    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. Unratedthis tornado

    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
Unrated
Date
May 23, 2016
Touchdown
9:24 PM CDT (02:24 UTC)
Lifted
9:34 PM CDT (02:34 UTC)
On the ground
10 minutes
Path length
2.0 miles (3.2 km)
Path width
50 yards (46 m)
Deaths
0
Injuries
0
County
Harper County
Touchdown point
36.617, -99.430
Lift-off point
36.645, -99.427
Record number
1605232024-01

The damage survey

2 damage points were recorded along this path by NWS OUN, in the Damage Assessment Toolkit the survey teams carry. The strongest indicator was rated EF0. The highest wind the damage implies is 74 mph.

  • barn ro of damage. per Woodward County EM.
  • barn roof damage. per Woodward County EM

Survey points are preliminary and are the raw material the published rating was built from. Source: NWS Damage Assessment Toolkit.

What the Weather Service recorded

Storms formed along a dryline in the panhandles on the 23rd. These storms slowly made their way into western Oklahoma and western north Texas late that evening. The southernmost storms eventually formed into an MCS and followed the Red River overnight into the early morning of the 24th.

Research meteorologists from Purdue University observed a tornado in southeast Harper County to the south-southeast of Selman. No damage is known to have occurred and data from the University of Massachusetts X-Pol operated by the Purdue researchers indicate peak tangential velocities of the tornado in the EF0 range.

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. One was issued for the county at another hour that day.

The county was under a tornado watch, issued at 20:38 UTC and running to 04:07 UTC.

Issued (UTC)ExpiredProductOffice
20:38 UTC04:07 UTCTornado WatchOUN
00:08 UTC00:45 UTCSevere Thunderstorm WarningOUN
00:44 UTC01:30 UTCSevere Thunderstorm WarningOUN
01:35 UTC02:15 UTCSevere Thunderstorm WarningOUN
01:58 UTC03:00 UTCSevere Thunderstorm WarningOUN
02:10 UTC03:00 UTCSevere Thunderstorm WarningOUN
02:21 UTC04:15 UTCFlood AdvisoryOUN
02:26 UTC03:00 UTCSevere Thunderstorm WarningOUN
02:29 UTC03:00 UTCTornado WarningOUN
02:56 UTC03:24 UTCSevere Thunderstorm WarningOUN
20:22 UTC02:51 UTCTornado WatchOUN

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 Enhanced Risk, with a 0.05 chance of a tornado within 25 miles. 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.

Dodge City, (KDDC), 00:00Z

2.4 hours before the tornado, 133 km from the path. May 24, 2016.

Skew-T log-pSkew-T log-p diagram, Dodge City, at 00:00Z on 2016-05-24Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 2915 joules per kilogram, CIN -2, lifted condensation level 1153 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, Dodge City, at 00:00Z on 2016-05-24The 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 132 square meters per square second, 0 to 6 km bulk shear 46 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
2915 J/kg
Mixed-layer CIN
-2 J/kg
Surface CAPE
4835 J/kg
Mixed-layer LCL
1153 m above ground
0-6 km bulk shear
46 kt
0-1 km bulk shear
15 kt
0-1 km storm-relative helicity
132 m²/s²
0-3 km storm-relative helicity
179 m²/s²
Significant tornado parameter
2.1
Supercell composite
15.2
0-3 km lapse rate
7.1 K/km

Open this sounding in Storm Lab

Dodge City, (KDDC), 12:00Z

9.6 hours after it, 133 km from the path. May 24, 2016.

Skew-T log-pSkew-T log-p diagram, Dodge City, at 12:00Z on 2016-05-24Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 2293 joules per kilogram, CIN -201, lifted condensation level 862 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, Dodge City, at 12:00Z on 2016-05-24The 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 251 square meters per square second, 0 to 6 km bulk shear 28 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
2293 J/kg
Mixed-layer CIN
-201 J/kg
Surface CAPE
2062 J/kg
Mixed-layer LCL
862 m above ground
0-6 km bulk shear
28 kt
0-1 km bulk shear
36 kt
0-1 km storm-relative helicity
251 m²/s²
0-3 km storm-relative helicity
238 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.4
0-3 km lapse rate
4.6 K/km

Open this sounding in Storm Lab

The surface observations

West Woodward (WWR), 23 km from the path, in the two hours either side.

Time (UTC)Temp (°F)Dew point (°F)WindGust (kt)Pressure (mb)Weather
00:35 UTC78.864.4170° 16 kt201006.4VCTS
00:55 UTC78.864.4170° 18 kt231007.1TS
01:15 UTC78.866.2160° 18 kt251007.5TS
01:35 UTC7766.2150° 23 kt281008.8VCTS
01:55 UTC73.466.2160° 25 kt301008.5VCTS
02:15 UTC71.666.2150° 21 kt321007.8TS
02:35 UTC71.666.2160° 26 kt351007.5-TSRA
02:55 UTC71.664.4150° 17 kt251009.8
03:15 UTC69.864.4150° 18 kt251010.2
03:35 UTC69.864.4160° 22 kt271010.8
03:55 UTC69.864.4150° 17 kt241011.2
04:15 UTC69.864.4150° 32 kt411009.8

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

The radar

The Vance AFB radar (KVNX), 117 km away, was scanning. The volume nearest the touchdown began at 02:23 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
00:59 UTCHAIL 15 Wnw MoorelandWoodward, OK
00:59 UTCHAIL 1.758 N WoodwardWoodward, OK
01:10 UTCHAIL 1.54 N WoodwardWoodward, OK
01:25 UTCTORNADO4 N WoodwardWoodward, OKESTIMATED LOCATION. SEVERAL REPORTS.
02:02 UTCHAIL 2.7510 N WoodwardWoodward, OK
02:05 UTCHAIL 39 N WoodwardWoodward, OKLOCATION ESTIMATED WITH RADAR
02:31 UTCTORNADO10 Ene Fort SupplyHarper, OKSEVERAL REPORTS.

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

This ground now

The live radar over the trackEvery 2016 tornado in OklahomaEvery tornado in Oklahoma since 1950Warnings in force in Oklahoma nowThe forecast where you are

The other tornadoes of May 23, 2016

4 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
May 232:37 PM CDTEF0Adams, NE0.150
May 234:41 PM CDTEF0Sioux, IA0.125
May 238:25 PM CDTEF0Woodward, OK2.7400$10,000
May 239:30 PM CDTEF3Hall, TX10.0800$150,000

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.