Tornadoes · United States · Texas · 2007

EF0 tornado, Colorado City, Texas, April 23, 2007

This EF0 tornado ran 4.0 miles across Mitchell County on April 23, 2007, touching down at 7:43 PM CDT and reaching 50 yards wide. It killed nobody, and did $8,000 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
April 23, 2007
Touchdown
7:43 PM CDT (00:43 UTC)
Lifted
7:56 PM CDT (00:56 UTC)
On the ground
13 minutes
Path length
4.0 miles (6.4 km)
Path width
50 yards (46 m)
Deaths
0
Injuries
0
Property damage
$8,000
County
Mitchell County
Touchdown point
32.400, -100.781
Lift-off point
32.400, -100.713
Record number
0704231843-01

What the Weather Service recorded

A southern stream shortwave trough approaching southwestern Texas enhanced thunderstorm development along and east of the dryline. Deep layer shear was quite strong and allowed a tornado to develop in Mitchell county.

A damage survey conducted by the National Weather Service determined that a tornado touched down just north of the intersection of Interstate 20 and southbound Texas Highway 208 near Colorado City and continued to parallel the Interstate to just northwest of Loraine.|This tornado remained over open fields inaccessible by roadways at its maximum intensity. Some damage found to a field irrigation system, power poles, including those near the intersection of Farm to Market Road 1899 and Interstate 20, vegetation, and damage to an Interstate 20 sign for exit 223 led the damage survey team to assign an EF0 rating to this tornado.

From NOAA NCEI's Storm Events Database, the narrative the local forecast office wrote for Storm Data.

The warnings

36 minutes of warning. NWS MAF issued a tornado warning for this county at 00:07 UTC, 36 minutes before the tornado touched down, in force until 01:00 UTC.

The county was under a tornado watch, issued at 22:37 UTC and running to 03:25 UTC.

Issued (UTC)ExpiredProductOffice
22:37 UTC03:25 UTCTornado WatchMAF
23:28 UTC00:15 UTCTornado WarningMAF
23:56 UTC01:00 UTCSevere Thunderstorm WarningMAF
00:07 UTC01:00 UTCTornado WarningMAF
00:58 UTC01:15 UTCTornado WarningMAF
15:00 UTC20:42 UTCFire Weather WatchMAF
15:00 UTC03:00 UTCRed Flag WarningMAF

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 General Thunderstorms Risk, with a 0.02 chance of a tornado within 25 miles. The outlook in force was issued at 20:01 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.

Midland Regional, TX (KMAF), 00:00Z

0.7 hours before the tornado, 146 km from the path. April 24, 2007.

Skew-T log-pSkew-T log-p diagram, Midland Regional, TX at 00:00Z on 2007-04-24Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 1676 joules per kilogram, CIN -24, lifted condensation level 2126 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, Midland Regional, TX at 00:00Z on 2007-04-24The 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 133 square meters per square second, 0 to 6 km bulk shear 43 knots.1939587897Sfc1 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
1676 J/kg
Mixed-layer CIN
-24 J/kg
Surface CAPE
2197 J/kg
Mixed-layer LCL
2126 m above ground
0-6 km bulk shear
43 kt
0-1 km bulk shear
15 kt
0-1 km storm-relative helicity
133 m²/s²
0-3 km storm-relative helicity
190 m²/s²
Significant tornado parameter
0.0
Supercell composite
6.9
0-3 km lapse rate
9.0 K/km

Open this sounding in Storm Lab

Midland Regional, TX (KMAF), 12:00Z

11.3 hours after it, 146 km from the path. April 24, 2007.

Skew-T log-pSkew-T log-p diagram, Midland Regional, TX at 12:00Z on 2007-04-24Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 1137 joules per kilogram, CIN -14, lifted condensation level 1158 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, Midland Regional, TX at 12:00Z on 2007-04-24The 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 7 square meters per square second, 0 to 6 km bulk shear 49 knots.1939587897Sfc1 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
1137 J/kg
Mixed-layer CIN
-14 J/kg
Surface CAPE
2513 J/kg
Mixed-layer LCL
1158 m above ground
0-6 km bulk shear
49 kt
0-1 km bulk shear
19 kt
0-1 km storm-relative helicity
7 m²/s²
0-3 km storm-relative helicity
100 m²/s²
Significant tornado parameter
0.1
Supercell composite
1.3
0-3 km lapse rate
6.2 K/km

Open this sounding in Storm Lab

The surface observations

Sweetwater/Avenger Field Airport (SWW), 27 km from the path, in the two hours either side.

Time (UTC)Temp (°F)Dew point (°F)WindGust (kt)Pressure (mb)Weather
22:45 UTC7760.8130° 15 kt241012.2
23:05 UTC75.260.8120° 14 kt201012.2
23:25 UTC75.260.8110° 13 kt161011.9
23:45 UTC73.460.8110° 14 kt221012.2
00:05 UTC73.460.8120° 19 kt221012.2
00:25 UTC71.660.8110° 13 kt191011.9
00:45 UTC71.660.8110° 13 kt181011.9
01:05 UTC71.660.890° 13 kt181011.9VCTS
01:25 UTC71.660.8320° 16 kt271012.2TS
01:45 UTC66.262.6210° 17 kt1013.2TS
02:05 UTC6862.6360° 5 kt1013.2TS
02:25 UTC6862.690° 11 kt171013.2

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

The radar

The San Angelo radar (KSJT), 117 km away, was scanning. The volume nearest the touchdown began at 00:42 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
23:34 UTCHAIL 1.751 N CoahomaHoward, TXGOLFBALL SIZE HAIL 1 MILE NORTH OF COAHOMA.
23:58 UTCHAIL 0.75KnappScurry, TXPENNY SIZE HAIL COVERING THE GROUND AT KNAPP.
00:09 UTCTORNADO9 W WestbrookMitchell, TXFUNNEL 1/2 WAY TO GROUND.
00:14 UTCHAIL 1.756 Nw Colorado CityMitchell, TXGOLFBALL SIZED HAIL AT 1808 AND AIRPORT ROAD.
00:20 UTCTORNADO6 Nw WestbrookMitchell, TXSPOTTER REPORTED A TORNADO 6 MILES NORTHWEST OF WESTBROOK.
00:38 UTCHAIL 1.757 Nw Colorado CityMitchell, TXGOLFBALL SIZED HAIL OBSERVED AT AIRPORT.
00:40 UTCHAIL 1.752 N Colorado CityMitchell, TXGOLFBALL SIZED HAIL 2 1/2 NORTH OF COLORADO CITY.
00:40 UTCTORNADOColorado CityMitchell, TXSPOTTER AND LAW ENFORCEMENT CONFIRMED TORNADO W/DEBRIS AT I-20 AND HIGHWAY 208.
00:43 UTCTORNADO1 N Colorado CityMitchell, TXSPOTTER REPORTED TORNADO WITH DEBRIS ON GROUND JUST NORTH OF COLORADO CITY. SPOTTER WAS LOCATED AT I-20 AND LASKEY ROAD.
00:50 UTCHAIL 1.753 N LoraineMitchell, TXKAUM RADIO STATION IN COLORADO CITY RELAYED REPORTS OF GOLFBALL SIZED HAIL 2 NORTH OF LONE WOLF MOUNTAIN ALSO MEASURED 1.3 INCHES OF RAIN IN 10 MINUTES.
00:52 UTCTORNADO2 W LoraineMitchell, TXSPOTTER REPORTED TORNADO 2 WEST OF LORAINE ALONG RAILROAD TRACKS.
00:56 UTCTORNADO1 E LoraineMitchell, TXSPOTTER REPORTED TORNADO 1 MILE EAST OF I-20 EXIT 224.
01:04 UTCTORNADO4 Nnw ChampionNolan, TXBRIEF TORNADO JUST OFF THE INTERSTATE EAST OF THE MITCHELL COUNTY LINE.
01:40 UTCHAIL 1.753 N SweetwaterNolan, TXGOLF BALL SIZE HAIL ON RANCH ROAD 419 NEAR THE FISHER AND NOLAN COUNTY LINE.
01:44 UTCHAIL 2.75N SweetwaterNolan, TXBASEBALL SIZE HAIL NOW REPORTED ON RANCH ROAD 419 NEAR THE FISHER AND NOLAN COUNTY LINE
02:00 UTCTORNADO5 Ne RoscoeNolan, TXWITH THE LIGHTNING...IT APPEARED THAT TORNADO WAS ON THE GROUND. LARGE WALL CLOUD JUST NORTH OF THE AIRPORT AS WELL.
02:20 UTCTORNADO2 N TrentTaylor, TXREPORT FROM KTXS TV OF A TORNADO JUST NORTH OF TRENT

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 TexasEvery tornado in Texas since 1950Warnings in force in Texas nowThe forecast where you are

The other tornadoes of April 23, 2007

24 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
April 236:14 PM CDTEF0Harper, OK0.230
April 236:51 PM CDTEF0Harper, OK0.230
April 236:47 PM MDTEF1Wallace, KS12.050$2,000
April 237:03 PM MDTEF0Wallace, KS5.075
April 238:04 PM CDTEF0Clark, KS1.450
April 238:04 PM CDTEF0Nolan, TX0.650
April 238:06 PM CDTEF0Val Verde, TX0.220
April 238:10 PM CDTEF1Clark, KS7.8150
April 238:22 PM CDTEF0Comanche, KS1.775
April 238:34 PM CDTEF0Val Verde, TX1.030$100,000
April 238:37 PM CDTEF0Comanche, KS1.650
April 239:00 PM CDTEF0Nolan, TX0.950
April 239:20 PM CDTEF0Taylor, TX0.350
April 239:38 PM CDTEF0Thomas, KS6.025$48,000
April 239:41 PM CDTEF0Jones, TX0.750
April 239:02 PM MDTEF0Sherman, KS0.510
April 2310:15 PM CDTEF1Thomas, KS13.050$16,000
April 2311:00 PM CDTEF1Rawlins, KS2.550
April 2311:15 PM CDTEF1Rawlins, KS12.5100$305,000
April 2311:44 PM CDTEF1Rawlins, KS6.075$26,000
April 2310:49 PM MDTEF0Yuma, CO0.510
April 2311:00 PM MDTEF0Phillips, CO0.150
April 2311:15 PM MDTEF0Chase, NE0.520
April 2311:16 PM MDTEF0Chase, NE0.320

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.