Tornadoes · United States · Oklahoma · 2015
EF3 tornado, Amber to Bridge Creek, Oklahoma, May 6, 2015
From Amber to Bridge Creek, this EF3 tornado ran 10.3 miles across Grady County on May 6, 2015, touching down at 4:33 PM CDT and reaching 1,500 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 mph
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 mphthis tornado
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
- EF3
- Date
- May 6, 2015
- Touchdown
- 4:33 PM CDT (21:33 UTC)
- Lifted
- 5:26 PM CDT (22:26 UTC)
- On the ground
- 53 minutes
- Path length
- 10.3 miles (16.6 km)
- Path width
- 1,500 yards (1372 m)
- Deaths
- 0
- Injuries
- 0
- County
- Grady County
- Touchdown point
- 35.158, -97.803
- Lift-off point
- 35.266, -97.698
- Record number
- 1505061533-01
The damage survey
312 damage points were recorded along this path by NWS OUN, in the Damage Assessment Toolkit the survey teams carry. The strongest indicator was rated EF3. The highest wind the damage implies is 149 mph.
- 100 yard length of livestock fence pulled to the north, 1 pole snapped.
- Two signs, tree and fence block (hollow) bent to the southwest. vortex south of here probable based on damage direction.
- 4 signs blown down to the north.
- Wood power pole snapped, leaning north.
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 potent Spring storm system took shape across the Southern and Central Plains. Strong surface cyclogenesis took shape during the day, allowing ample moisture to return northward with strong southerly flow. At the same time, a strong upper level shortwave trough allowed strong mid level westerlies to overspread much of the Plains region. With large instability and wind shear, the stage was set for widespread severe storm development. Storms initiated within the open warm sector ahead of the dryline. The first storm developed near Lawton and moved northeast along I-44 into parts of central Oklahoma, resulting in several tornadoes and large hail. Additional supercells spawned tornadoes across northern Oklahoma, and the slow moving nature of storms lead to several occurrences of flash flooding. Storms continued well into the night.
A large tornado developed east of Amber and moved slowly northeast near or along Interstate 44, then turned north impacting the community of Bridge Creek. The most intense damage occurred just east of the Interstate 44 and H.E. Bailey Turnpike Spur near Bridge Creek where EF3 damage was observed to a home (DI 2, DOD 7) and a mobile home (DI 4, DOD 12). A pickup truck was also thrown for several hundred yards in this area. Numerous homes and other buildings were damaged along the tornado path.
From NOAA NCEI's Storm Events Database, the narrative the local forecast office wrote for Storm Data.
The warnings
21 minutes of warning. NWS OUN issued a tornado warning for this county at 21:12 UTC, 21 minutes before the tornado touched down, in force until 21:45 UTC.
The county was under a tornado watch, issued at 18:25 UTC and running to 01:51 UTC.
| Issued (UTC) | Expired | Product | Office |
|---|---|---|---|
| 04:41 UTC | 07:45 UTC | Flash Flood Warning | OUN |
| 05:27 UTC | 05:58 UTC | Severe Thunderstorm Warning | OUN |
| 07:11 UTC | 10:15 UTC | Flood Advisory | OUN |
| 18:25 UTC | 01:51 UTC | Tornado Watch | OUN |
| 20:10 UTC | 20:45 UTC | Tornado Warning | OUN |
| 20:43 UTC | 21:15 UTC | Tornado Warning | OUN |
| 21:12 UTC | 21:45 UTC | Tornado Warning | OUN |
| 21:43 UTC | 22:30 UTC | Tornado Warning | OUN |
| 22:21 UTC | 23:00 UTC | Severe Thunderstorm Warning | OUN |
| 22:25 UTC | 22:34 UTC | Tornado Warning | OUN |
| 23:06 UTC | 14:00 UTC | Flash Flood Warning | OUN |
| 23:12 UTC | 00:00 UTC | Severe Thunderstorm Warning | OUN |
| 23:31 UTC | 00:00 UTC | Tornado Warning | OUN |
| 23:57 UTC | 00:30 UTC | Tornado Warning | OUN |
| 00:02 UTC | 00:45 UTC | Severe Thunderstorm Warning | OUN |
| 00:09 UTC | 01:00 UTC | Severe Thunderstorm Warning | OUN |
| 00:25 UTC | 01:00 UTC | Tornado Warning | OUN |
| 00:29 UTC | 01:00 UTC | Severe Thunderstorm Warning | OUN |
| 00:45 UTC | 01:30 UTC | Severe Thunderstorm Warning | OUN |
| 00:59 UTC | 01:45 UTC | Tornado Warning | OUN |
| 01:04 UTC | 01:45 UTC | Severe Thunderstorm Warning | OUN |
| 01:14 UTC | 02:00 UTC | Severe Thunderstorm Warning | OUN |
| 01:28 UTC | 02:00 UTC | Tornado Warning | OUN |
| 01:34 UTC | 02:15 UTC | Severe Thunderstorm Warning | OUN |
| 01:51 UTC | 06:31 UTC | Tornado 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. The outlook in force was issued at 20:00 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), 12:00Z
9.6 hours before the tornado, 32 km from the path. May 6, 2015.
- Mixed-layer CAPE
- 1226 J/kg
- Mixed-layer CIN
- -16 J/kg
- Surface CAPE
- 1997 J/kg
- Mixed-layer LCL
- 562 m above ground
- 0-6 km bulk shear
- 27 kt
- 0-1 km bulk shear
- 32 kt
- 0-1 km storm-relative helicity
- 219 m²/s²
- 0-3 km storm-relative helicity
- 308 m²/s²
- Significant tornado parameter
- 1.2
- Supercell composite
- 9.1
- 0-3 km lapse rate
- 6.6 K/km
Norman, OK (KOUN), 00:00Z
2.4 hours after it, 32 km from the path. May 7, 2015.
- Mixed-layer CAPE
- 1821 J/kg
- Mixed-layer CIN
- -7 J/kg
- Surface CAPE
- 2793 J/kg
- Mixed-layer LCL
- 916 m above ground
- 0-6 km bulk shear
- 36 kt
- 0-1 km bulk shear
- 29 kt
- 0-1 km storm-relative helicity
- 246 m²/s²
- 0-3 km storm-relative helicity
- 343 m²/s²
- Significant tornado parameter
- 3.0
- Supercell composite
- 19.3
- 0-3 km lapse rate
- 6.8 K/km
The surface observations
Chickasha Municipal Airport (CHK), 23 km from the path, in the two hours either side.
| Time (UTC) | Temp (°F) | Dew point (°F) | Wind | Gust (kt) | Pressure (mb) | Weather |
|---|---|---|---|---|---|---|
| 19:35 UTC | 73.4 | 68 | 170° 14 kt | 20 | 1010.5 | |
| 19:55 UTC | 73.4 | 68 | 160° 14 kt | 20 | 1010.5 | -RA |
| 20:15 UTC | 71.6 | 69.8 | 160° 13 kt | 1010.2 | RA | |
| 20:35 UTC | 71.6 | 69.8 | 110° 7 kt | 1010.2 | +RA | |
| 20:55 UTC | 69.8 | 68 | 340° 21 kt | 24 | 1008.8 | +RA |
| 21:15 UTC | 68 | 64.4 | 40° 15 kt | 42 | 1008.8 | |
| 21:35 UTC | 68 | 62.6 | 330° 23 kt | 30 | 1009.1 | |
| 21:55 UTC | 68 | 62.6 | 50° 7 kt | 1008.8 | ||
| 22:15 UTC | 71.6 | 68 | 130° 9 kt | 18 | 1008.5 | |
| 22:35 UTC | 68 | 64.4 | 130° 10 kt | 1007.5 | ||
| 22:55 UTC | 73.4 | 69.8 | 140° 14 kt | 1007.8 | ||
| 23:15 UTC | 73.4 | 69.8 | 140° 10 kt | 1007.1 |
From the Iowa Environmental Mesonet's archive of airport observations.
The radar
The Norman radar (KTLX), 45 km away, was scanning. The volume nearest the touchdown began at 21:31 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 |
|---|---|---|---|---|
| 19:42 UTC | TORNADO | 3 E Apache | Caddo, OK | STORM CHASER REPORTED A TORNADO DEVELOPED ABOUT 242 PM 2.5 MILES EAST OF APACHE AND MOVED NORTHEAST. |
| 19:45 UTC | TSTM WND DMG | 3 S Stecker | Caddo, OK | TREE LIMBS LARGER THAN 2 INCHES IN DIAMETER DOWNED BY WINDS. |
| 19:53 UTC | TORNADO | 4 Nw Cyril | Caddo, OK | |
| 20:05 UTC | HAIL 1 | 6 S Anadarko | Caddo, OK | |
| 20:12 UTC | HAIL 2 | 6 S Verden | Grady, OK | |
| 20:16 UTC | HAIL 1.5 | 3 S Anadarko | Caddo, OK | |
| 20:23 UTC | HAIL 1.5 | Verden | Grady, OK | |
| 21:33 UTC | TORNADO | 3 E Amber | Grady, OK | |
| 21:33 UTC | TORNADO | 4 E Amber | Grady, OK | UPDATED. EF3 TORNADO MOVED FROM 4.5 MILES EAST OF AMBER TO BRIDGE CREEK TO 4 MILES NORTH-NORTHEAST OF BRIDGE CREEK AROUND 526 PM. MANY STRUCTURES WERE DAMAGED OR DESTROYED. |
| 22:33 UTC | TORNADO | 2 Se Newcastle | Mcclain, OK | EF1 TORNADO. TWO OUTBUILDINGS WERE DESTROYED AND TREES WERE DAMAGED IN SOUTHEAST NEWCASTLE. |
| 22:46 UTC | TORNADO | 4 Wnw Norman | Cleveland, OK | BRIEF TOUCHDOWN AT THE INTERSECTION OF 48TH AND ROBINSON. |
| 22:46 UTC | TORNADO | 4 Wnw Norman | Cleveland, OK | UPDATED. EF0 TORNADO. BRIEF TOUCHDOWN AT THE INTERSECTION OF NORTHWEST 60TH AND ROBINSON. |
| 22:51 UTC | TSTM WND GST 70 | 5 Wnw Norman | Cleveland, OK | ROTATING WALL CLOUD REPORTED AS WELL. |
| 22:53 UTC | TORNADO | 4 Nw Norman | Cleveland, OK | UPDATED. EF1 TORNADO. TORNADO BEGAN JUST SOUTH OF NORTHWEST 36TH AVENUE AND ROCK CREEK ROAD AND MOVED GENERALLY NORTH THROUGH WEST NORMAN TO NEAR NORTHWEST 36TH AVENUE AND INDIAN HILLS ROAD AT AROUND 610 PM. |
| 22:55 UTC | HAIL 1 | 7 E Anadarko | Caddo, OK | |
| 23:00 UTC | TSTM WND DMG | 3 Wnw Norman | Cleveland, OK | DAMAGE TO A HOTEL AT INTERSTATE 35 AND ROBINSON STREET. |
| 23:00 UTC | TORNADO | 4 Nw Norman | Cleveland, OK | TORNADO WITH DAMAGE IN NORTHWEST NORMAN... NEAR NORTHWEST 36TH AVENUE AND TECUMSEH ROAD AND NEARBY AREAS. |
| 23:04 UTC | HAIL 1 | 7 W Anadarko | Caddo, OK | |
| 23:10 UTC | TSTM WND GST 58 | 2 Nw Norman | Cleveland, OK | |
| 23:13 UTC | FLASH FLOOD | Newcastle | Mcclain, OK | NUMEROUS ROADS AND DITCHES FLOODED NEAR HWY 62. |
| 23:30 UTC | HAIL 1.75 | Tuttle | Grady, OK | DAMAGE TO CARS AND SIDING... ONE WINDOW IN HOME BROKEN. |
| 23:45 UTC | TORNADO | 5 Nnw Verden | Caddo, OK | UPDATED LOCATION. |
| 23:45 UTC | TORNADO | 5 N Verden | Grady, OK | |
| 23:56 UTC | FLASH FLOOD | 1 S Moore | Cleveland, OK | 19TH STREET IS IMPASSABLE DUE TO VERY HIGH WATER UNDER THE RAILROAD OVERPASS. |
| 00:12 UTC | FLASH FLOOD | 3 Nnw Warr Acres | Oklahoma, OK | STRANDED VEHICLES DUE TO HIGH WATER AND EXCESSIVE RAINFALL |
From the Iowa Environmental Mesonet's archive of National Weather Service local storm reports.
This ground now
The live radar over the trackEvery 2015 tornado in OklahomaEvery tornado in Oklahoma since 1950Warnings in force in Oklahoma nowThe forecast where you are
The other tornadoes of May 6, 2015
47 more were confirmed in the United States that day.
| Date | Time | Rating | Where | Path (mi) | Width (yd) | Deaths | Injuries | Damage |
|---|---|---|---|---|---|---|---|---|
| May 6 | 2:58 AM CDT | EF0 | Creek, OK | 1.5 | 100 | |||
| May 6 | 2:24 PM CDT | EF0 | Lincoln, KS | 10.7 | 100 | $25,000 | ||
| May 6 | 2:45 PM CDT | EF0 | Caddo, OK | 2.0 | 50 | |||
| May 6 | 2:53 PM CDT | EF0 | Caddo, OK | 0.5 | 50 | |||
| May 6 | 3:31 PM CDT | EF0 | Jewell, KS | 1.0 | 25 | |||
| May 6 | 3:55 PM CDT | EF2 | Jewell, KS | 12.6 | 350 | 1 | $1.5 million | |
| May 6 | 4:18 PM CDT | EF1 | Adams, NE | 3.9 | 300 | $1.5 million | ||
| May 6 | 4:37 PM CDT | EF0 | Major, OK | 0.1 | 20 | |||
| May 6 | 4:38 PM CDT | EF1 | Nuckolls, NE | 9.5 | 200 | $250,000 | ||
| May 6 | 4:48 PM CDT | EF0 | Grady, OK to KS, NE | 0.3 | 50 | |||
| May 6 | 4:48 PM CDT | EF2 | Nuckolls, KS to NE | 20.1 | 400 | $4.3 million | ||
| May 6 | 4:49 PM CDT | EF3 | Sedgwick, KS | 16.5 | 300 | 1 | $630,000 | |
| May 6 | 4:54 PM CDT | EF1 | Jewell, KS | 4.3 | 250 | $250,000 | ||
| May 6 | 5:04 PM CDT | EF1 | Jewell, KS | 3.1 | 60 | $5,000 | ||
| May 6 | 5:08 PM CDT | EF1 | Republic, KS | 2.1 | 75 | |||
| May 6 | 5:10 PM CDT | EF0 | Republic, KS | 3.1 | 50 | |||
| May 6 | 5:15 PM CDT | EF0 | Garfield, OK | 0.1 | 10 | |||
| May 6 | 5:20 PM CDT | EF2 | Republic, KS to NE | 36.2 | 800 | $1.0 million | ||
| May 6 | 5:26 PM CDT | EF0 | Thayer, NE | 1.8 | 100 | $500,000 | ||
| May 6 | 5:28 PM CDT | EF0 | Thayer, NE | 1.0 | 30 | |||
| May 6 | 5:33 PM CDT | EF1 | McClain, OK | 1.0 | 200 | |||
| May 6 | 5:38 PM CDT | EF0 | Sedgwick, KS | 0.3 | 50 | |||
| May 6 | 5:45 PM CDT | EF0 | Hall, NE | 0.0 | 25 | |||
| May 6 | 5:46 PM CDT | EF0 | Cleveland, OK | 0.5 | 25 | |||
| May 6 | 5:53 PM CDT | EF1 | Cleveland, OK | 3.3 | 1,000 | |||
| May 6 | 6:33 PM CDT | EF0 | Dewey, OK | 0.3 | 30 | |||
| May 6 | 6:41 PM CDT | EF0 | Caddo, OK | 3.5 | 200 | |||
| May 6 | 6:56 PM CDT | EF0 | Grant, OK | 0.3 | 20 | |||
| May 6 | 7:14 PM CDT | EF3 | Republic, KS | 1.9 | 100 | |||
| May 6 | 7:28 PM CDT | EF0 | Republic, KS | 0.0 | 50 | |||
| May 6 | 7:35 PM CDT | EF0 | Harper, KS | 0.3 | 50 | |||
| May 6 | 7:38 PM CDT | EF1 | Republic, KS | 2.4 | 75 | |||
| May 6 | 7:49 PM CDT | EF0 | Grady, OK | 0.5 | 40 | |||
| May 6 | 8:11 PM CDT | EF0 | Grady, OK | 3.5 | 200 | |||
| May 6 | 8:33 PM CDT | EF0 | Cloud, KS | 0.3 | 75 | |||
| May 6 | 8:38 PM CDT | EF0 | Ottawa, KS | 0.0 | 50 | |||
| May 6 | 8:41 PM CDT | EF3 | Oklahoma, OK | 2.0 | 700 | 12 | ||
| May 6 | 8:49 PM CDT | EF2 | Archer, TX | 12.0 | 400 | |||
| May 6 | 8:55 PM CDT | EF0 | Ottawa, KS | 0.3 | 50 | |||
| May 6 | 9:10 PM CDT | EF0 | Washington, KS | 6.0 | 50 | |||
| May 6 | 9:27 PM CDT | EF0 | Cloud, KS | 8.8 | 75 | |||
| May 6 | 9:37 PM CDT | EF0 | Throckmorton, TX | 3.4 | 440 | |||
| May 6 | 9:56 PM CDT | EF1 | Washington, KS | 4.0 | 75 | |||
| May 6 | 10:00 PM CDT | EF0 | Throckmorton, TX | 1.2 | 100 | |||
| May 6 | 10:36 PM CDT | EF0 | Washington, KS | 0.3 | 75 | |||
| May 6 | 10:49 PM CDT | EF1 | Gage, NE | 7.7 | 500 | |||
| May 6 | 11:00 PM CDT | EF0 | Throckmorton, TX | 0.0 | 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.