Tornadoes · United States · Texas · 2002

F0 tornado, Ozona, Texas, April 7, 2002

This F0 tornado ran 0.5 miles across Crockett County on April 7, 2002, touching down at 3:03 PM CDT and reaching 50 yards wide. It killed nobody.

The rating scale

Tracks are drawn in the color of the rating. The Fujita scale rates the damage rather than measuring the wind: the speeds are what that damage is taken to imply.

  1. F040 to 72 mphthis tornado

    Light damage. Surface peeled off some roofs, gutters and siding damaged, branches broken, shallow-rooted trees pushed over.

  2. F173 to 112 mph

    Moderate damage. Roofs badly stripped, mobile homes overturned or badly damaged, exterior doors lost, windows broken.

  3. F2113 to 157 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. F3158 to 206 mph

    Severe damage. Whole stories of well-built houses destroyed, large buildings badly damaged, trains overturned, trees debarked, heavy cars lifted and thrown.

  5. F4207 to 260 mph

    Devastating damage. Well-built houses leveled, structures with weak foundations moved some distance, cars thrown and large missiles generated.

  6. F5261 to 318 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
F0
Date
April 7, 2002
Touchdown
3:03 PM CDT (20:03 UTC)
Path length
0.5 miles (0.8 km)
Path width
50 yards (46 m)
Deaths
0
Injuries
0
County
Crockett County
Touchdown point
30.580, -101.200
Lift-off point
30.580, -101.200
Record number
541

What the Weather Service recorded

Severe thunderstorms rolled across much of West Central Texas during the afternoon and evening hours of the 7th. Two supercells produced a total of 5 tornadoes, 3 across the northern Big Country in Throckmorton County and 2 more across the Northern Edwards Plateau in Crockett County. Although one of the tornadoes in Throckmorton was about three quarters of a mile wide and stayed on the ground for 16 minutes, it fortunately crossed open farmland, striking no homes were causing no injuries. Damage was more extensive with the southern supercell, with tennis ball size hail causing tens of thousands of dollars of damage to several ranch houses in eastern Crockett County. Other storms produced hail up to golf ball size across parts of the Concho Valley and Heartland.

Law enforcement reported a brief tornado touch down 8 miles southwest of Ozona. No injuries or damage was reported.

A storm chaser spotted a second tornado from the main storm, passing south of Ozona in central Crockett County. Again, no injuries or damage was reported.

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

The warnings

6 minutes of warning. NWS SJT issued a tornado warning for this county at 19:57 UTC, 6 minutes before the tornado touched down, in force until 20:45 UTC.

Issued (UTC)ExpiredProductOffice
19:02 UTC20:00 UTCTornado WarningSJT
19:57 UTC20:45 UTCTornado WarningSJT
20:58 UTC22:00 UTCSevere Thunderstorm WarningSJT

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 Moderate Risk, with a 0.15 chance of a tornado within 25 miles. The outlook in force was issued at 19:52 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.

Del Rio, TX (KDRT), 12:00Z

8.1 hours before the tornado, 139 km from the path. April 7, 2002.

Skew-T log-pSkew-T log-p diagram, Del Rio, TX at 12:00Z on 2002-04-07Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 1329 joules per kilogram, CIN -91, lifted condensation level 591 meters above ground. Wind barbs in knots down the right edge.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°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, Del Rio, TX at 12:00Z on 2002-04-07The 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 311 square meters per square second, 0 to 6 km bulk shear 55 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
1329 J/kg
Mixed-layer CIN
-91 J/kg
Surface CAPE
1504 J/kg
Mixed-layer LCL
591 m above ground
0-6 km bulk shear
55 kt
0-1 km bulk shear
26 kt
0-1 km storm-relative helicity
311 m²/s²
0-3 km storm-relative helicity
328 m²/s²
Significant tornado parameter
2.1
Supercell composite
8.6
0-3 km lapse rate
4.5 K/km

Open this sounding in Storm Lab

Del Rio, TX (KDRT), 00:00Z

3.9 hours after it, 139 km from the path. April 8, 2002.

Skew-T log-pSkew-T log-p diagram, Del Rio, TX at 00:00Z on 2002-04-08Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 622 joules per kilogram, CIN -173, lifted condensation level 1496 meters above ground. Wind barbs in knots down the right edge.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°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, Del Rio, TX at 00:00Z on 2002-04-08The 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 -1 square meters per square second, 0 to 6 km bulk shear 46 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
622 J/kg
Mixed-layer CIN
-173 J/kg
Surface CAPE
826 J/kg
Mixed-layer LCL
1496 m above ground
0-6 km bulk shear
46 kt
0-1 km bulk shear
13 kt
0-1 km storm-relative helicity
-1 m²/s²
0-3 km storm-relative helicity
9 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.3
0-3 km lapse rate
6.2 K/km

Open this sounding in Storm Lab

The surface observations

San Angelo/Mathis (SJT), 109 km from the path, in the two hours either side.

Time (UTC)Temp (°F)Dew point (°F)WindGust (kt)Pressure (mb)Weather
18:53 UTC8257200° 15 kt1003
19:53 UTC7954240° 12 kt1002.7
20:29 UTC7753.6250° 14 kt1002.7TS
20:45 UTC71.648.2280° 13 kt201003TS
20:53 UTC7248280° 11 kt1003.4TS
21:53 UTC6850280° 11 kt1002

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

This ground now

The live radar over the trackEvery 2002 tornado in TexasEvery tornado in Texas since 1950Warnings in force in Texas nowThe forecast where you are

The other tornadoes of April 7, 2002

10 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
April 72:46 PM CDTF0Crockett, TX0.550
April 73:33 PM CDTF0Throckmorton, TX0.220
April 73:34 PM CDTF2Throckmorton, TX7.01,500$10,000
April 73:50 PM CDTF0Throckmorton, TX0.220
April 74:10 PM CDTF0Val Verde, TX0.230
April 74:40 PM CDTF0Val Verde, TX0.230
April 75:20 PM CDTF0Kinney, TX3.050
April 76:15 PM CDTF0Uvalde, TX0.220
April 77:40 PM CDTF2Medina, TX1.0100$200,000
April 78:00 PM CDTF1Frio, TX0.120$10,000

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.