Tornadoes · United States · Oklahoma · 2023
EF0 tornado, Pearson to Maud, Oklahoma, May 11, 2023
From Pearson to Maud, this EF0 tornado ran 1.7 miles across Pottawatomie County on May 11, 2023, touching down at 10:16 PM CDT and reaching 300 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.
EF065 to 85 mphthis tornado
Light damage. Surface peeled off some roofs, gutters and siding damaged, branches broken, shallow-rooted trees pushed over.
EF186 to 110 mph
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
- EF0
- Date
- May 11, 2023
- Touchdown
- 10:16 PM CDT (03:16 UTC)
- Lifted
- 10:21 PM CDT (03:21 UTC)
- On the ground
- 5 minutes
- Path length
- 1.7 miles (2.7 km)
- Path width
- 300 yards (274 m)
- Deaths
- 0
- Injuries
- 0
- County
- Pottawatomie County
- Touchdown point
- 35.129, -96.822
- Lift-off point
- 35.152, -96.812
- Record number
- 2305112116-01
The damage survey
5 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.
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
A deepening upper/low pressure system slowly approached portions of the Central Plains on the 11th. Combined with increasing instability and wind shear, a favorable environment for severe weather (capable of producing all severe hazards) developed across much of western into central Oklahoma on the evening of the 11th. Numerous supercell thunderstorms developed and produced twelve tornadoes and large hail across portions of these areas.
Pottawatomie County storm spotters observed a brief tornado about 4 miles north-northwest of Asher, or about 2.5 miles southwest of Pearson. No damage was reported and the specific path is estimated.
Television storm chasers observed a tornado west of Maud. An NWS storm survey team observed EF0 tree damage, although this tornado was likely stronger than EF0.
From NOAA NCEI's Storm Events Database, the narrative the local forecast office wrote for Storm Data.
The warnings
4 minutes of warning. NWS OUN issued a tornado warning for this county at 03:12 UTC, 4 minutes before the tornado touched down, in force until 03:45 UTC.
The county was under a tornado watch, issued at 20:46 UTC and running to 07:00 UTC.
| Issued (UTC) | Expired | Product | Office |
|---|---|---|---|
| 20:46 UTC | 07:00 UTC | Tornado Watch | OUN |
| 01:43 UTC | 02:30 UTC | Tornado Warning | OUN |
| 01:57 UTC | 02:30 UTC | Tornado Warning | OUN |
| 02:26 UTC | 03:15 UTC | Tornado Warning | OUN |
| 02:27 UTC | 02:57 UTC | Tornado Warning | OUN |
| 03:08 UTC | 04:00 UTC | Severe Thunderstorm Warning | OUN |
| 03:12 UTC | 03:45 UTC | Tornado Warning | OUN |
| 03:16 UTC | 04:00 UTC | Tornado Warning | OUN |
| 20:42 UTC | 01:46 UTC | Severe Thunderstorm Watch | OUN |
| 21:00 UTC | 18:00 UTC | Flood Watch | OUN |
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 0.10 chance of a tornado within 25 miles, in the hatched area where significant tornadoes were expected. The outlook in force was issued at 01:05 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), 00:00Z
3.3 hours before the tornado, 54 km from the path. May 12, 2023.
- Mixed-layer CAPE
- 2756 J/kg
- Mixed-layer CIN
- -1 J/kg
- Surface CAPE
- 3551 J/kg
- Mixed-layer LCL
- 721 m above ground
- 0-6 km bulk shear
- 39 kt
- 0-1 km bulk shear
- 18 kt
- 0-1 km storm-relative helicity
- 162 m²/s²
- 0-3 km storm-relative helicity
- 237 m²/s²
- Significant tornado parameter
- 2.0
- Supercell composite
- 11.5
- 0-3 km lapse rate
- 6.5 K/km
Norman, OK (KOUN), 12:00Z
8.7 hours after it, 54 km from the path. May 12, 2023.
- Mixed-layer CAPE
- 3321 J/kg
- Mixed-layer CIN
- -23 J/kg
- Surface CAPE
- 3874 J/kg
- Mixed-layer LCL
- 603 m above ground
- 0-6 km bulk shear
- 32 kt
- 0-1 km bulk shear
- 28 kt
- 0-1 km storm-relative helicity
- 313 m²/s²
- 0-3 km storm-relative helicity
- 339 m²/s²
- Significant tornado parameter
- 3.9
- Supercell composite
- 20.3
- 0-3 km lapse rate
- 6.0 K/km
The surface observations
Seminole (SRE), 20 km from the path, in the two hours either side.
| Time (UTC) | Temp (°F) | Dew point (°F) | Wind | Gust (kt) | Pressure (mb) | Weather |
|---|---|---|---|---|---|---|
| 01:35 UTC | 73.4 | 69.8 | 120° 4 kt | 1008.1 | VCTS | |
| 01:55 UTC | 73.4 | 69.8 | 0° 0 kt | 1008.5 | ||
| 02:15 UTC | 73.4 | 69.8 | 130° 6 kt | 1008.5 | VCTS | |
| 02:35 UTC | 73.4 | 69.8 | 130° 5 kt | 1008.5 | TS | |
| 02:50 UTC | 73.4 | 69.8 | 140° 7 kt | 1008.5 | TS | |
| 03:15 UTC | 73.4 | 69.8 | 180° 8 kt | 17 | 1009.1 | VCTS RA |
| 03:35 UTC | 73.4 | 71.6 | 140° 9 kt | 1008.8 | -TSRA | |
| 03:55 UTC | 73.4 | 71.6 | 140° 10 kt | 17 | 1008.5 | -RA |
| 04:15 UTC | 73.4 | 71.6 | 4 kt | 18 | 1008.5 | VCTS |
| 04:35 UTC | 73.4 | 71.6 | 4 kt | 1008.8 | VCTS BR | |
| 04:55 UTC | 73.4 | 71.6 | 230° 4 kt | 1008.1 | -RA | |
| 05:15 UTC | 73.4 | 71.6 | 110° 4 kt | 1008.8 | BR |
From the Iowa Environmental Mesonet's archive of airport observations.
The radar
The Norman radar (KTLX), 47 km away, was scanning. The volume nearest the touchdown began at 03:16 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 |
|---|---|---|---|---|
| 02:07 UTC | TORNADO | Noble | Cleveland, OK | SPOTTER NETWORK REPORT OF TORNADO IN NOBLE. |
| 02:33 UTC | TORNADO | 5 Wsw Lake Thunderbird | Cleveland, OK | SPOTTERS AND BROADCAST MEDIA REPORT A TORNADO SOUTHWEST OF LAKE THUNDERBIRD. |
| 03:00 UTC | HAIL 1 | 2 Sse Noble | Cleveland, OK | SPOTTERNETWORK REPORT. |
| 03:09 UTC | HAIL 1 | 1 N Bowlegs | Seminole, OK | |
| 03:21 UTC | TORNADO | 3 W Maud | Pottawatomie, OK | SPOTTERS AND BROADCAST MEDIA OBSERVED A TORNADO APPROXIMATELY 3 MILES WEST OF MAUD. |
| 04:03 UTC | HAIL 1 | 1 N Stonewall | Pontotoc, OK |
From the Iowa Environmental Mesonet's archive of National Weather Service local storm reports.
This ground now
The live radar over the trackEvery 2023 tornado in OklahomaEvery tornado in Oklahoma since 1950Warnings in force in Oklahoma nowThe forecast where you are
The other tornadoes of May 11, 2023
32 more were confirmed in the United States that day.
| Date | Time | Rating | Where | Path (mi) | Width (yd) | Deaths | Injuries | Damage |
|---|---|---|---|---|---|---|---|---|
| May 11 | 6:06 AM CDT | EF1 | Caddo Parish, LA | 2.6 | 130 | $10,000 | ||
| May 11 | 7:55 AM CDT | EF1 | De Soto Parish, LA | 0.2 | 130 | $50,000 | ||
| May 11 | 8:03 AM CDT | EF1 | Grant Parish, LA | 0.5 | 80 | |||
| May 11 | 8:21 AM CDT | EF1 | Webster Parish, LA | 0.1 | 60 | $20,000 | ||
| May 11 | 10:59 AM CDT | EF1 | Union Parish, LA | 0.6 | 80 | |||
| May 11 | 12:41 PM CDT | EF1 | Ashley, AR | 0.5 | 140 | $40,000 | ||
| May 11 | 12:57 PM CDT | EF1 | Cheyenne, KS to CO | 5.2 | 100 | |||
| May 11 | 1:35 PM CDT | Unrated | Rawlins, KS | 1.2 | 100 | |||
| May 11 | 1:39 PM CDT | Unrated | Rawlins, KS | 1.8 | 75 | |||
| May 11 | 2:01 PM MDT | Unrated | Dundy, NE | 3.0 | 75 | |||
| May 11 | 4:33 PM MDT | EF0 | Wallace, KS | 8.5 | 100 | |||
| May 11 | 4:41 PM MDT | EF0 | Wallace, KS | 3.2 | 100 | |||
| May 11 | 4:45 PM MDT | EF1 | Wallace, KS | 1.3 | 175 | |||
| May 11 | 4:45 PM MDT | Unrated | Cheyenne, CO | 1.1 | 150 | |||
| May 11 | 4:46 PM MDT | Unrated | Cheyenne, CO | 0.7 | 75 | |||
| May 11 | 5:09 PM MDT | EF0 | Wallace, KS | 6.6 | 100 | |||
| May 11 | 6:25 PM CDT | EF0 | Grady, OK | 1.0 | 20 | |||
| May 11 | 6:25 PM CDT | Unrated | Logan, KS | 5.8 | 100 | |||
| May 11 | 5:47 PM MDT | Unrated | Sherman, KS | 0.8 | 75 | |||
| May 11 | 6:57 PM CDT | Unrated | Grady, OK | 2.9 | 50 | |||
| May 11 | 7:29 PM CDT | Unrated | Thomas, KS | 1.5 | 75 | |||
| May 11 | 7:36 PM CDT | EF0 | Grady, OK | 0.4 | 30 | $4,000 | ||
| May 11 | 7:42 PM CDT | EF0 | McClain, OK | 2.1 | 30 | $5,000 | ||
| May 11 | 7:45 PM CDT | Unrated | Grady, OK | 0.2 | 20 | |||
| May 11 | 7:51 PM CDT | EF0 | Grant, KS | 0.0 | 1 | |||
| May 11 | 8:04 PM CDT | EF0 | Grady, OK | 1.5 | 75 | |||
| May 11 | 8:12 PM CDT | EF0 | McClain, OK | 0.4 | 30 | |||
| May 11 | 8:29 PM CDT | EF1 | McClain, OK | 9.4 | 250 | $100,000 | ||
| May 11 | 9:03 PM CDT | EF1 | Cleveland, OK | 2.3 | 300 | $200,000 | ||
| May 11 | 9:20 PM CDT | EF1 | Palo Pinto, TX | 1.3 | 75 | |||
| May 11 | 9:33 PM CDT | EF0 | Cleveland, OK | 0.2 | 25 | $10,000 | ||
| May 11 | 9:47 PM CDT | Unrated | Pottawatomie, OK | 0.2 | 50 |
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.