Tornadoes · United States · Oklahoma · 2018

EF0 tornado, Little Chief to Pawhuska Arpt, Oklahoma, May 19, 2018

From Little Chief to Pawhuska Arpt, this EF0 tornado ran 0.9 miles across Osage County on May 19, 2018, touching down at 3:04 PM CDT and reaching 100 yards wide. It killed nobody, and did $5,000 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 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 19, 2018
Touchdown
3:04 PM CDT (20:04 UTC)
Lifted
3:05 PM CDT (20:05 UTC)
On the ground
1 minutes
Path length
0.9 miles (1.4 km)
Path width
100 yards (91 m)
Deaths
0
Injuries
0
Property damage
$5,000
County
Osage County
Touchdown point
36.676, -96.494
Lift-off point
36.687, -96.483
Record number
1805191404-01

The damage survey

33 damage points were recorded along this path by NWS TSA, in the Damage Assessment Toolkit the survey teams carry. The strongest indicator was rated EF0. The highest wind the damage implies is 94 mph.

  • under roof overhang of insurance agent retail bldg on east side.
  • view of insurance agent bldg facing NE
  • . view facing west with insurance bldg to right.
  • ballfield back fence bent but no other damage.

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

Severe thunderstorms developed during the afternoon of the 19th along a stationary front that extended across northern Oklahoma. The storms formed over north central Oklahoma and then moved through eastern Oklahoma producing two tornadoes, damaging wind gusts, and large hail up to golfball size.

This tornado was reported to the NWS by multiple storm chasers. It remained over open country for much of its lifecycle, but an NWS storm survey team found a barn that received some roof damage as well as trees that had large limbs snapped by this tornado. Based on this damage, maximum estimated wind in the tornado was 75 to 85 mph.

This tornado was reported to the NWS by multiple storm chasers. It remained over open country for much of its lifecycle, but an NWS storm survey team found a barn that had its roof blown off and some trees that had large limbs snapped by this tornado. Based on this damage, maximum estimated wind in the tornado was 75 to 85 mph.

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

The warnings

20 minutes of warning. NWS TSA issued a tornado warning for this county at 19:44 UTC, 20 minutes before the tornado touched down, in force until 20:30 UTC.

The county was under a severe thunderstorm watch, issued at 19:31 UTC and running to 02:31 UTC.

Issued (UTC)ExpiredProductOffice
19:23 UTC20:30 UTCSevere Thunderstorm WarningTSA
19:31 UTC02:31 UTCSevere Thunderstorm WatchTSA
19:44 UTC20:30 UTCTornado WarningTSA
20:15 UTC20:59 UTCSevere Thunderstorm WarningTSA
23:03 UTC23:44 UTCSevere Thunderstorm WarningTSA
03:25 UTC03:56 UTCSevere Thunderstorm 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 Enhanced Risk, with a 0.05 chance of a tornado within 25 miles. The outlook in force was issued at 19:57 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.

Norman, OK (KOUN), 12:00Z

8.1 hours before the tornado, 182 km from the path. May 19, 2018.

Skew-T log-pSkew-T log-p diagram, Norman, OK at 12:00Z on 2018-05-19Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 755 joules per kilogram, CIN -268, lifted condensation level 1934 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, Norman, OK at 12:00Z on 2018-05-19The 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 76 square meters per square second, 0 to 6 km bulk shear 16 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
755 J/kg
Mixed-layer CIN
-268 J/kg
Surface CAPE
999 J/kg
Mixed-layer LCL
1934 m above ground
0-6 km bulk shear
16 kt
0-1 km bulk shear
17 kt
0-1 km storm-relative helicity
76 m²/s²
0-3 km storm-relative helicity
121 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0
0-3 km lapse rate
5.9 K/km

Open this sounding in Storm Lab

Norman, OK (KOUN), 00:00Z

3.9 hours after it, 182 km from the path. May 20, 2018.

Skew-T log-pSkew-T log-p diagram, Norman, OK at 00:00Z on 2018-05-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 1717 joules per kilogram, CIN -9, lifted condensation level 1316 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, Norman, OK at 00:00Z on 2018-05-20The 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 -14 square meters per square second, 0 to 6 km bulk shear 26 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
1717 J/kg
Mixed-layer CIN
-9 J/kg
Surface CAPE
1973 J/kg
Mixed-layer LCL
1316 m above ground
0-6 km bulk shear
26 kt
0-1 km bulk shear
8 kt
0-1 km storm-relative helicity
-14 m²/s²
0-3 km storm-relative helicity
49 m²/s²
Significant tornado parameter
0.0
Supercell composite
-1.0
0-3 km lapse rate
7.1 K/km

Open this sounding in Storm Lab

The surface observations

Bartlesville/Philli (BVO), 43 km from the path, in the two hours either side.

Time (UTC)Temp (°F)Dew point (°F)WindGust (kt)Pressure (mb)Weather
18:15 UTC140° 7 kt1010.5
18:20 UTC150° 8 kt1010.5
18:25 UTC140° 8 kt1010.5
18:30 UTC140° 8 kt1010.5
18:35 UTC140° 9 kt151010.2
18:40 UTC130° 9 kt1010.2
18:50 UTC170° 10 kt1010.2
18:53 UTC8570170° 8 kt141010.2
18:55 UTC140° 7 kt1010.2
19:00 UTC160° 10 kt1010.2
19:05 UTC170° 6 kt1009.8
19:15 UTC140° 7 kt1009.8
19:20 UTC190° 10 kt1009.5
19:25 UTC160° 9 kt1009.5
19:30 UTC160° 8 kt1009.1
19:40 UTC180° 5 kt1009.8
19:45 UTC190° 5 kt1010.2
19:50 UTC180° 4 kt1010.2
19:53 UTC8468 3 kt1010.2
19:55 UTC230° 4 kt1010.2
20:00 UTC230° 6 kt1010.5
20:10 UTC0° 0 kt1010.5
20:15 UTC0° 0 kt1010.8
20:20 UTC0° 0 kt1010.8
20:25 UTC0° 0 kt1010.5
20:31 UTC7968350° 3 kt1010.5VCTS
20:35 UTC260° 5 kt1011.9
20:38 UTC8070 1012.9TS
20:40 UTC
20:43 UTC7062300° 12 kt301012.9TS HZ
20:45 UTC 16 kt+RA
20:46 UTC6662290° 14 kt301012.9+TSRA FG
20:50 UTC300° 9 kt181012.2+RA FG
20:53 UTC6461310° 8 kt271012.9-TSRA FG
20:55 UTC300° 7 kt-RA BR
20:57 UTC6360300° 7 kt181013.2-TSRA BR
21:04 UTC6259360° 8 kt1012.2TS
21:05 UTC360° 8 kt1012.2
21:15 UTC360° 3 kt1011.9
21:20 UTC360° 4 kt1011.9
21:25 UTC350° 3 kt1011.5
21:30 UTC0° 0 kt1011.2
21:35 UTC0° 0 kt1010.8
21:40 UTC0° 0 kt1010.8
21:41 UTC65610° 0 kt1010.8
21:45 UTC0° 0 kt1010.8
21:50 UTC0° 0 kt1011.2
21:53 UTC67620° 0 kt1011.2
21:55 UTC0° 0 kt1011.2

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

The radar

The Tulsa radar (KINX), 100 km away, was scanning. The volume nearest the touchdown began at 20:03 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
19:33 UTCHAIL 1MarlandNoble, OK
19:45 UTCTSTM WND DMGFairfaxOsage, OKROOFS BLOWN OFF OR DAMAGED TO BUSINESSES, LOTS OF TREE DAMAGE, POWER LINES DOWN, DAMAGE TO HIGH SCHOOL.
19:49 UTCTSTM WND GST 637 Sw BurbankOsage, OK
19:59 UTCTORNADO12 W PawhuskaOsage, OKBRIEF TORNADO TOUCHDOWN ALONG HIGHWAY 60 WEST OF PAWHUSKA AND SOUTH OF FORAKER.
20:06 UTCTSTM WND DMG2 Ne RalstonOsage, OKREPORT OF LOTS OF TREE DAMAGE AND METAL ROOF OFF A BUILDING.
20:16 UTCTSTM WND DMGPawhuskaOsage, OKBROKEN TREE LIMB FROM THUNDERSTORM WINDS.
20:35 UTCTSTM WND GST 704 Ne BigheartOsage, OK
20:40 UTCTSTM WND DMGBartlesvilleWashington, OKBILLBOARD SIGNS BLOWN DOWN. WINDS ESTIMATED TO 60 MPH.
20:40 UTCHAIL 0.752 W BartlesvilleOsage, OK
20:40 UTCHAIL 1.75BartlesvilleWashington, OK
20:48 UTCTSTM WND DMG4 W CopanWashington, OKAWNINGS DAMAGED OR BLOWN OFF SEVERAL CAMPERS/RVS BY THUNDERSTORM WINDS.
20:48 UTCNON-TSTM WND DMG4 W CopanWashington, OKAWNINGS DAMAGED OR BLOWN OFF SEVERAL CAMPERS/RVS BY THUNDERSTORM WINDS.
20:55 UTCTSTM WND GST 602 Ene CopanWashington, OK

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

This ground now

The live radar over the trackEvery 2018 tornado in OklahomaEvery tornado in Oklahoma since 1950Warnings in force in Oklahoma nowThe forecast where you are

The other tornadoes of May 19, 2018

5 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
May 192:59 PM CDTEF0Osage, OK1.9100$2,000
May 196:25 PM CDTEF1Polk, MO2.3100$20,000
May 196:28 PM CDTEF1Polk, MO2.0100$20,000
May 199:36 PM EDTEF1Bedford, VA1.0100$25,000
May 1912:17 AM CDTEF0McClain, OK7.050$10,000

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.