Tornadoes · United States · Oklahoma · 2007

EF0 tornado, Union City to El Reno, Oklahoma, May 8, 2007

From Union City to El Reno, this EF0 tornado ran 2.2 miles across Canadian County on May 8, 2007, touching down at 11:26 PM CDT and reaching 40 yards wide. It killed nobody, and did $100,000 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 8, 2007
Touchdown
11:26 PM CDT (04:26 UTC)
Lifted
11:30 PM CDT (04:30 UTC)
On the ground
4 minutes
Path length
2.2 miles (3.5 km)
Path width
40 yards (37 m)
Deaths
0
Injuries
0
Property damage
$100,000
County
Canadian County
Touchdown point
35.380, -97.973
Lift-off point
35.419, -97.978
Record number
0705082226-01

What the Weather Service recorded

An upper level storm system moved slowly east northeast through southeast Arizona and southwest New Mexico. A couple of disturbances rotated around the storm system and moved over the southern plains during the morning and afternoon hours. One disturbance moved over Oklahoma during the morning hours, with the other moving over Oklahoma during the evening hours. A stationary front remained located south of the Red River, with another front establishing itself over the southeast third of Oklahoma. Showers and thunderstorms developed and moved over the main body of Oklahoma during the morning hours. Widespread flash flooding was reported over central Oklahoma, with rivers rising out of their banks. After a lull in precipitation for a few hours the other disturbance moved over Oklahoma during the late afternoon and evening hours. Widespread showers and thunderstorms developed over southwest Oklahoma and continued to develop into central and southern Oklahoma. Large hail and severe wind gusts were reported, with flash flooding and river flooding continuing to be a concern due to the heavy rainfall earlier in the day. Supercell thunderstorms formed in southwest Oklahoma producing one tornado near Lake Ellsworth. As the showers and storms continued to develop and move northeast, a mesoscale convective vorticity maximum (MCV) developed. In the vicinity of this MCV, transient circulations on many scales were observed in the storm-relative radar velocity fields and in the storm motions themselves. Some of the circulations briefly tightened to tornado scale causing damage west of Minco, west of Union City, and in El Reno. Monetary damages were estimated.

A tornado formed near EW112 Road just east of Reformatory Road. Trees were knocked over or snapped on two properties. The most significant damage occurred near the intersection of EW111 Road and Reformatory Road where a wood and metal garage was essentially destroyed and a barn sustained some damage to a wall panel, however a car inside the garage suffered minimal damage. A grain bin was blown to the north, and power poles were pushed from upright in this area. Trees were damaged from this location to about 1 mile north-northwest. Monetary damages were estimated.|

A tornado developed and moved north through parts of El Reno. The first damage occurred in a complex of industrial/commercial buildings is located on the southwest corner of I-40 and Hwy 81. One building suffered minor roof damage with the roofing peeled away. Another metal building had partial peeling of the side paneling, a large garage door blown in and the business���s dumpster was rolled 100 ft to the west. An outbuilding supply business had its several garage doors blown in and a display outbuilding collapsed and was moved. Some trees in the area were damaged and the damage varied over a wide range. Trees closer to the interstate had large branches and trunks snapped, while trees closer to Hwy 81 were either tipped or limbs up to 6��� were snapped. Farther to the west, a building that was under construction had some building material blown to the north northeast towards the area of apparent touchdown. Two businesses just south southwest of the touchdown point also had damage to their garage doors.||Directly across I-40 from the touchdown point was a car dealership. The main building at the dealership had minimal damage and most vehicles in the lot had no damage. One light pole was knocked over and a large sign for the dealership was damaged. A double wide mobile home, which was used as an office at the dealership, was knocked over on its side. Several cars towards the extreme northwest corner of the lot exhibited damage though the original locations of the vehicles are in question. Billboards around the lot were either destroyed or folded over. Farther to the northwest a farm house with outbuildings sustained damage. Most damage appeared to be suffered by the outbuildings. The damage appeared minor with roof and side panels peeled, though one of the buildings sustained some damage to its structure. The tornado then entered into an industrial area. A building west of the farm house sustained damage to its office area and a section of side paneling was peeled. Roofing from the Oklahoma Gas and Electric building, which was across the street, also impacted the northeast corner of the building with enough force to cause a significant dent in the panel. A flag pole at this building was also bent about 50 degrees. The building seemed to have sustained the most damage in the area. It appeared most of the roof was gone, a tree was snapped in two and the power lines were snapped in two. Further, the roof of the small office area appeared to have been partially lifted. A pole near the building also appears to have bent a bit. Other buildings near the building had other damage to siding and roofs.||Along Hwy 81, north of Oklahoma Gas and Electric, several buildings in the industrial/commercial area sustained damage. A convenience store had its windows blown out, a garage door blown out, and a portion of the roof was removed. Metal framed buildings to the west of this area failed at the ends of the buildings but the center portions of the framing remained intact. One structure in particular lost most of its roof and it is believed that this roof actually scraped along and removed the roof to a small strip mall. A metal building to the north of this strip mall had a garage door blown in and two panels were pushed in towards the bottom of the panel on its south side. On the north side the building had 3 garage doors blown in and the northeast corner sustained side panel damage. Across Hwy 81, a snow cone hut was spun about 270 degrees and a metal lining peeled off. Two metal light poles near the hut were damaged; one was bent and another was snapped off its base. To the north of this area a building sustained damage to its roof. People were present inside the building when it was struck but no one was injured. Three power poles, one towards the highway and two near the building were snapped. A storage shed on the north side of the building's parking lot had a garage door blown in; also, plastic skylights were blown out to locations unknown. Power poles just to the north along a side road were blown over and one was snapped. West of this location was a farm supply store which had grain bins blown over and some into a nearby pond. North of the store was a cluster of trees which had a variety of damage. The final damage points were along Choctaw Rd. At the corner of Choctaw and Elm, a metal building had its roof rotated on top it and a power pole near it was snapped. The neighborhood west of Choctaw Rd had some tree and power pole damage. Also the neighborhood northeast of Hwy 81 and Elm sustained probable microburst damage. Monetary damages were estimated.

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 00:55 UTC and running to 05:00 UTC.

Issued (UTC)ExpiredProductOffice
10:27 UTC17:00 UTCFlood WatchOUN
13:36 UTC16:15 UTCFlash Flood WarningOUN
00:55 UTC05:00 UTCTornado WatchOUN
03:33 UTC06:30 UTCFlash Flood WarningOUN
03:46 UTC04:30 UTCSevere Thunderstorm WarningOUN
04:26 UTC05:15 UTCSevere Thunderstorm WarningOUN
04:48 UTC05:15 UTCTornado WarningOUN
05:09 UTC05:45 UTCTornado WarningOUN
05:43 UTC06:15 UTCSevere Thunderstorm WarningOUN

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 00:35 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

4.4 hours before the tornado, 56 km from the path. May 9, 2007.

Skew-T log-pSkew-T log-p diagram, Norman, OK at 00:00Z on 2007-05-09Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 763 joules per kilogram, CIN -23, lifted condensation level 784 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 2007-05-09The 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 49 square meters per square second, 0 to 6 km bulk shear 21 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
763 J/kg
Mixed-layer CIN
-23 J/kg
Surface CAPE
1786 J/kg
Mixed-layer LCL
784 m above ground
0-6 km bulk shear
21 kt
0-1 km bulk shear
8 kt
0-1 km storm-relative helicity
49 m²/s²
0-3 km storm-relative helicity
116 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.1
0-3 km lapse rate
6.4 K/km

Open this sounding in Storm Lab

Norman, OK (KOUN), 12:00Z

7.6 hours after it, 56 km from the path. May 9, 2007.

Skew-T log-pSkew-T log-p diagram, Norman, OK at 12:00Z on 2007-05-09Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 83 joules per kilogram, CIN -84, lifted condensation level 991 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 2007-05-09The 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 105 square meters per square second, 0 to 6 km bulk shear 22 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
83 J/kg
Mixed-layer CIN
-84 J/kg
Surface CAPE
21 J/kg
Mixed-layer LCL
991 m above ground
0-6 km bulk shear
22 kt
0-1 km bulk shear
27 kt
0-1 km storm-relative helicity
105 m²/s²
0-3 km storm-relative helicity
127 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0
0-3 km lapse rate
4.9 K/km

Open this sounding in Storm Lab

The surface observations

El Reno (RQO), 9 km from the path, in the two hours either side.

Time (UTC)Temp (°F)Dew point (°F)WindGust (kt)Pressure (mb)Weather
02:53 UTC69.86850° 9 kt1016.3-TSRA
03:13 UTC69.866.250° 9 kt1016.9-TSRA
03:33 UTC686850° 10 kt1016.6-VCTSRA
03:53 UTC686850° 14 kt1015.9VCTSRA
04:13 UTC686840° 16 kt1014.6+TSRA
04:58 UTC69.868
05:13 UTC6868
05:18 UTC
05:33 UTC
05:53 UTC64.462.6200° 8 kt1015.9
06:13 UTC64.462.6200° 6 kt1015.2
06:33 UTC64.462.6180° 6 kt1015.2

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

The radar

The Norman radar (KTLX), 64 km away, was scanning. The volume nearest the touchdown began at 04:27 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
04:45 UTCTORNADOEl RenoCanadian, OKAPPARENT TORNADO IN EL RENO. TORNADO CROSSED I-40 NEAR MM 126...OVERTURNING AT LEAST THREE 18 WHEELERS AND DAMAGING BILLBOARDS. SOME STRUCTURAL DAMAGE REPORTED IN EL RENO...ALONG WITH NUMEROUS TREES AND POWER LINES DOWN.
05:20 UTCTSTM WND GST 655 Wnw El RenoCanadian, OKNORTHWEST WIND OF 65 MPH MEASURED BY OKLAHOMA MESONET.
05:30 UTCFLASH FLOOD6 E KingfisherKingfisher, OKHWY 33 CLOSED DUE TO HIGH WATER.
05:30 UTCTSTM WND GST 70PiedmontCanadian, OK

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

This ground now

The live radar over the trackEvery 2007 tornado in OklahomaEvery tornado in Oklahoma since 1950Warnings in force in Oklahoma nowThe forecast where you are

The other tornadoes of May 8, 2007

8 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
May 84:11 PM CDTEF0Shackelford, TX6.550
May 85:30 PM CDTEF1Haskell, TX4.245$10,000
May 85:54 PM CDTEF0Throckmorton, TX0.840
May 88:15 PM CDTEF0Comanche, OK0.230
May 810:54 PM CDTEF1Grady, OK1.530$70,000
May 811:43 PM CDTEF1Canadian, OK1.8150$3.0 million
May 812:08 AM CDTEF1Canadian, OK0.680
May 812:21 AM CDTEF1Canadian, OK0.230$25,000

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.