Tornadoes · United States · Oklahoma · 2007

EF0 tornado, Forest Park, Oklahoma, May 7, 2007

This EF0 tornado ran 1.5 miles across Oklahoma County on May 7, 2007, touching down at 2:32 AM CDT and reaching 30 yards wide. It killed nobody, and did $25,000 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 7, 2007
Touchdown
2:32 AM CDT (07:32 UTC)
Lifted
2:33 AM CDT (07:33 UTC)
On the ground
1 minutes
Path length
1.5 miles (2.4 km)
Path width
30 yards (27 m)
Deaths
0
Injuries
0
Property damage
$25,000
County
Oklahoma County
Touchdown point
35.509, -97.478
Lift-off point
35.522, -97.461
Record number
0705070132-01

What the Weather Service recorded

Thunderstorms began early in the morning on the 6th, continued most of the day and into the early morning hours of the 7th. An upper level low pressure remained anchored over Colorado during this time period. Surface low pressure was located over southeast Colorado, with a dryline extending south along the Oklahoma and Texas panhandle border. Outflow boundaries were also present from previous thunderstorm activity. These boundaries were important in the formation of thunderstorms throughout the day. Moisture was in abundance that day, along with very strong instability. Wind shear remained quite favorable for supercell thunderstorms. Most of the thunderstorms began over the northwest half of Oklahoma, but moved south and east into the morning and afternoon hours of the 7th. Large hail, high winds, and tornadoes were common, with flooding rains also present. One small supercell thunderstorm developed east of the main thunderstorm area during the evening and produced two small tornadoes as it moved to the north. Two other tornadoes occurred in the early morning hours as thunderstorms moving northeast into central Oklahoma interacted with gust front boundaries from previous thunderstorms.

This tornado occurred within the city limits of Oklahoma City. A narrow path of considerable tree damage was found from just northwest of the intersection of NE 36th Street and Martin Luther King Avenue to just east of the intersection of Interstate 35 and NE 50th Street, including a swath about 30 yards wide across Lincoln Park Golf Course. Damage consisted of numerous small to medium branches broken off trees, as well as numerous large rotted branches. A number of small trees in wet soil were also pushed over along this path. Minor shingle damage was noted to a home just east of I-35 and NE 50th Street, and minor gutter damage was noted to a large metal building just to the southwest of the house. A couple of wooden fences were pushed over and a small canopy was torn near the start of the path. However other structures in or near the path showed little discernible 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.

The county was under a tornado watch, issued at 04:54 UTC and running to 10:00 UTC.

Issued (UTC)ExpiredProductOffice
14:20 UTC19:00 UTCTornado WatchOUN
19:00 UTC22:50 UTCTornado WatchOUN
04:54 UTC10:00 UTCTornado WatchOUN
07:19 UTC08:00 UTCSevere Thunderstorm WarningOUN
09:16 UTC23:00 UTCFlood WatchOUN
12:03 UTC15:00 UTCFlash Flood 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 05:54 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

7.5 hours before the tornado, 33 km from the path. May 7, 2007.

Skew-T log-pSkew-T log-p diagram, Norman, OK at 00:00Z on 2007-05-07Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 2453 joules per kilogram, CIN -2, lifted condensation level 905 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 2007-05-07The 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 187 square meters per square second, 0 to 6 km bulk shear 27 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
2453 J/kg
Mixed-layer CIN
-2 J/kg
Surface CAPE
3683 J/kg
Mixed-layer LCL
905 m above ground
0-6 km bulk shear
27 kt
0-1 km bulk shear
26 kt
0-1 km storm-relative helicity
187 m²/s²
0-3 km storm-relative helicity
236 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), 12:00Z

4.5 hours after it, 33 km from the path. May 7, 2007.

Skew-T log-pSkew-T log-p diagram, Norman, OK at 12:00Z on 2007-05-07Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 301 joules per kilogram, CIN -191, lifted condensation level 545 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 2007-05-07The 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 15 square meters per square second, 0 to 6 km bulk shear 47 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
301 J/kg
Mixed-layer CIN
-191 J/kg
Surface CAPE
0 J/kg
Mixed-layer LCL
545 m above ground
0-6 km bulk shear
47 kt
0-1 km bulk shear
7 kt
0-1 km storm-relative helicity
15 m²/s²
0-3 km storm-relative helicity
178 m²/s²
Significant tornado parameter
0.0
Supercell composite
27.6
0-3 km lapse rate
4.1 K/km

Open this sounding in Storm Lab

The surface observations

Tinker Afb (TIK), 13 km from the path, in the two hours either side.

Time (UTC)Temp (°F)Dew point (°F)WindGust (kt)Pressure (mb)Weather
05:55 UTC75.269.4180° 12 kt211012.2
06:55 UTC7568.7180° 10 kt171012.9-TSRA BR
07:38 UTC71.669.8240° 11 kt1014.9+TSRA BR
07:49 UTC66.262.6270° 29 kt371012.2+TSRA BR
07:55 UTC65.562260° 30 kt371013.5+TSRA BR
08:04 UTC62.660.8200° 12 kt611013.9+TSRA BR
08:25 UTC64.460.8360° 4 kt1014.9TSRA BR
08:41 UTC62.660.810° 5 kt1015.6TSRA
08:55 UTC62.860.470° 5 kt1014.2-TSRA

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

The radar

The Norman radar (KTLX), 27 km away, was scanning. The volume nearest the touchdown began at 07:33 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
07:33 UTCHAIL 1Oklahoma CityOklahoma, OKQUARTER SIZE HAIL AT OKLAHOMA COMMUNITY COLLEGE 74TH AND SOUTH MAY
07:45 UTCTSTM WND DMG8 E NormanCleveland, OKLARGE TREE LIMBS BLOWN DOWN. SOME LARGE BRADFORD PEAR TREES SNAPPED AT THE BASE.
07:45 UTCTSTM WND GST 602 E GoldsbyMcclain, OK
07:54 UTCTSTM WND GST 70Tinker Air Force BaseOklahoma, OKGUST TO 61 KNOTS AT TINKER AIR FORCE BASE.

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 7, 2007

1 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
May 73:15 AM CDTEF0Pottawatomie, OK0.120$8,000

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.