Tornadoes · United States · Oklahoma · 2019
EF1 tornado, Mulhall, Oklahoma, August 26, 2019
This EF1 tornado ran 2.2 miles across Logan County on August 26, 2019, touching down at 8:12 PM CDT and reaching 50 yards wide. It killed nobody, and did $75,000 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
- August 26, 2019
- Touchdown
- 8:12 PM CDT (01:12 UTC)
- Lifted
- 8:19 PM CDT (01:19 UTC)
- On the ground
- 7 minutes
- Path length
- 2.2 miles (3.5 km)
- Path width
- 50 yards (46 m)
- Deaths
- 0
- Injuries
- 0
- Property damage
- $75,000
- County
- Logan County
- Touchdown point
- 36.105, -97.443
- Lift-off point
- 36.078, -97.461
- Record number
- 1908261912-01
The damage survey
6 damage points were recorded along this path by NWS OUN, in the Damage Assessment Toolkit the survey teams carry. The strongest indicator was rated EF1. The highest wind the damage implies is 94 mph.
- 3 trees uprooted, but 2 seem dead. From David Ewoldt.
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 highly unstable airmass and a cold front produced intense thunderstorms with widespread various severe hazards including widespread wind damage across the OKC metro area.
This tornado moved south and southwest in northern Logan County northwest of Mulhall. One shop building was destroyed, but otherwise damage was confined to trees along the path.
From NOAA NCEI's Storm Events Database, the narrative the local forecast office wrote for Storm Data.
The warnings
0 minutes of warning. NWS OUN issued a tornado warning for this county at 01:12 UTC, 0 minutes before the tornado touched down, in force until 01:27 UTC.
The county was under a severe thunderstorm watch, issued at 22:10 UTC and running to 05:00 UTC.
| Issued (UTC) | Expired | Product | Office |
|---|---|---|---|
| 17:00 UTC | 18:14 UTC | Heat Advisory | OUN |
| 18:14 UTC | 00:15 UTC | Excessive Heat Warning | OUN |
| 22:10 UTC | 05:00 UTC | Severe Thunderstorm Watch | OUN |
| 00:44 UTC | 01:30 UTC | Severe Thunderstorm Warning | OUN |
| 01:12 UTC | 01:27 UTC | Tornado Warning | OUN |
| 01:26 UTC | 02:30 UTC | Severe Thunderstorm Warning | OUN |
| 01:45 UTC | 04:45 UTC | Flood Advisory | OUN |
| 01:48 UTC | 02:30 UTC | Severe Thunderstorm Warning | OUN |
| 01:57 UTC | 02:15 UTC | Tornado Warning | OUN |
| 02:03 UTC | 02:45 UTC | Severe Thunderstorm Warning | OUN |
| 02:19 UTC | 05:15 UTC | Flood Warning | OUN |
| 02:36 UTC | 06:58 UTC | Flash Flood Warning | 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 Slight Risk, with a 0.02 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.
Norman, OK (KOUN), 00:00Z
1.2 hours before the tornado, 97 km from the path. August 27, 2019.
- Mixed-layer CAPE
- 4637 J/kg
- Mixed-layer CIN
- -27 J/kg
- Surface CAPE
- 6823 J/kg
- Mixed-layer LCL
- 1565 m above ground
- 0-6 km bulk shear
- 29 kt
- 0-1 km bulk shear
- 14 kt
- 0-1 km storm-relative helicity
- 105 m²/s²
- 0-3 km storm-relative helicity
- 239 m²/s²
- Significant tornado parameter
- 1.8
- Supercell composite
- 28.0
- 0-3 km lapse rate
- 6.7 K/km
Norman, OK (KOUN), 12:00Z
10.8 hours after it, 97 km from the path. August 27, 2019.
- Mixed-layer CAPE
- 2447 J/kg
- Mixed-layer CIN
- -77 J/kg
- Surface CAPE
- 1561 J/kg
- Mixed-layer LCL
- 743 m above ground
- 0-6 km bulk shear
- 41 kt
- 0-1 km bulk shear
- 7 kt
- 0-1 km storm-relative helicity
- -10 m²/s²
- 0-3 km storm-relative helicity
- -10 m²/s²
- Significant tornado parameter
- -0.1
- Supercell composite
- -2.8
- 0-3 km lapse rate
- 4.3 K/km
The surface observations
Guthrie (GOK), 27 km from the path, in the two hours either side.
| Time (UTC) | Temp (°F) | Dew point (°F) | Wind | Gust (kt) | Pressure (mb) | Weather |
|---|---|---|---|---|---|---|
| 23:15 UTC | 120° 8 kt | 1005.8 | ||||
| 23:20 UTC | 120° 8 kt | 1006.1 | ||||
| 23:25 UTC | 120° 8 kt | 1006.1 | ||||
| 23:30 UTC | 120° 8 kt | 1006.1 | ||||
| 23:35 UTC | 120° 5 kt | 1005.8 | ||||
| 23:40 UTC | 130° 5 kt | 1005.8 | ||||
| 23:45 UTC | 130° 5 kt | 1005.8 | ||||
| 23:50 UTC | 140° 8 kt | 1005.8 | ||||
| 23:53 UTC | 93 | 78 | 140° 8 kt | 1005.8 | ||
| 23:55 UTC | 150° 9 kt | 1005.8 | ||||
| 00:00 UTC | 160° 9 kt | 1005.8 | ||||
| 00:05 UTC | 150° 8 kt | 1005.4 | ||||
| 00:10 UTC | 150° 8 kt | 1005.4 | ||||
| 00:15 UTC | 150° 7 kt | 1005.4 | ||||
| 00:20 UTC | 160° 8 kt | 1005.1 | ||||
| 00:25 UTC | 160° 8 kt | 1005.1 | ||||
| 00:30 UTC | 150° 9 kt | 1005.1 | ||||
| 00:35 UTC | 150° 10 kt | 1005.1 | ||||
| 00:40 UTC | 150° 11 kt | 1004.4 | ||||
| 00:45 UTC | 150° 10 kt | 1004.7 | ||||
| 00:50 UTC | 140° 8 kt | 1005.1 | ||||
| 00:53 UTC | 90 | 77 | 150° 9 kt | 1004.7 | ||
| 00:55 UTC | 11 kt | 1004.4 | ||||
| 01:00 UTC | 150° 10 kt | 1004.7 | ||||
| 01:05 UTC | 10 kt | 1004.7 | ||||
| 01:10 UTC | 130° 9 kt | 1005.4 | ||||
| 01:13 UTC | 90 | 76 | 130° 11 kt | 1005.1 | VCTS | |
| 01:15 UTC | 140° 11 kt | 1004.7 | ||||
| 01:20 UTC | 150° 13 kt | 18 | 1003.4 | |||
| 01:25 UTC | 89 | 76 | 130° 14 kt | 19 | 1003.7 | TS |
| 01:30 UTC | 120° 15 kt | 1004.1 | ||||
| 01:35 UTC | 100° 11 kt | 1004.7 | ||||
| 01:40 UTC | 1005.8 | HZ | ||||
| 01:45 UTC | 1006.1 | |||||
| 01:50 UTC | ||||||
| 01:55 UTC | ||||||
| 02:00 UTC | ||||||
| 02:01 UTC | 1011.5 | TS | ||||
| 02:55 UTC | 1010.2 | |||||
| 03:10 UTC |
From the Iowa Environmental Mesonet's archive of airport observations.
The radar
The Norman radar (KTLX), 86 km away, was scanning. The volume nearest the touchdown began at 01:09 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 |
|---|---|---|---|---|
| 01:55 UTC | TSTM WND GST 77 | 4 E Cedar Valley | Logan, OK | . |
| 01:55 UTC | TSTM WND GST 77 | 4 E Cedar Valley | Logan, OK | |
| 01:57 UTC | TORNADO | 3 Ssw Seward | Logan, OK | TORNADO DEBRIS SIGNATURE ON KTLX RADAR ALONG WITH VELOCITY COUPLET. DAMAGE REPORTED IN THE AREA. DETAILS PENDING FURTHER INVESTIGATION. |
| 02:00 UTC | TSTM WND GST 60 | 2 S Guthrie | Logan, OK | SMALL SHEET-METAL SHED DESTROYED. TIME ESTIMATED. |
| 02:00 UTC | TSTM WND GST 69 | Guthrie | Logan, OK | ASOS REPORT |
| 02:00 UTC | TSTM WND GST 69 | Guthrie | Logan, OK | ASOS REPORT. |
| 02:00 UTC | TSTM WND GST 72 | 1 S Guthrie | Logan, OK | ASOS REPORT- CORRECTED WIND SPEED |
| 02:00 UTC | TSTM WND GST 72 | 1 S Guthrie | Logan, OK | ASOS REPORT- CORRECTED WIND SPEED. |
| 02:00 UTC | TSTM WND GST 72 | Guthrie | Logan, OK | ASOS REPORT- CORRECTED WIND SPEED |
| 02:00 UTC | TSTM WND GST 72 | Guthrie | Logan, OK | ASOS REPORT- CORRECTED WIND SPEED. |
| 02:20 UTC | TSTM WND GST 87 | 4 Se Piedmont | Canadian, OK | ASOS MEASUREMENT |
| 02:20 UTC | TSTM WND GST 87 | 4 Se Piedmont | Canadian, OK | ASOS MEASUREMENT. |
| 03:21 UTC | FLASH FLOOD | 1 S Edmond | Oklahoma, OK | MPING REPORT, ROAD CLOSURES, CARS STRANDED. |
| 03:56 UTC | TSTM WND DMG | 6 Nnw Edmond | Logan, OK | TRAMPOLINE POLE AS A PROJECTILE THROUGH HOUSE. TWITTER PICTURE |
| 03:56 UTC | TSTM WND DMG | 6 Nnw Edmond | Logan, OK | TRAMPOLINE POLE AS A PROJECTILE THROUGH HOUSE. TWITTER PICTURE. |
From the Iowa Environmental Mesonet's archive of National Weather Service local storm reports.
This ground now
The live radar over the trackEvery 2019 tornado in OklahomaEvery tornado in Oklahoma since 1950Warnings in force in Oklahoma nowThe forecast where you are
The other tornadoes of August 26, 2019
5 more were confirmed in the United States that day.
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.