EF0 tornado, Clegg, Texas, May 10, 2012

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.

Rating

EF0

Date

May 10, 2012

Touchdown

7:14 PM CDT (00:14 UTC)

Lifted

7:26 PM CDT (00:26 UTC)

On the ground

12 minutes

Path length

4.9 miles (7.9 km)

Path width

100 yards (91 m)

Deaths

0

Injuries

0

County

Live Oak County

Touchdown point

28.079, -98.328

Lift-off point

28.083, -98.248

Record number

1205101814-01

A strongly unstable air mass developed over South Texas in advance of a stalled frontal boundary over south-central Texas on May 10th. As a strong upper level low pressure system over northern Mexico approached the region providing strong shear in the atmosphere, an outbreak of supercell thunderstorms occurred across South Texas producing an unprecedented 16 tornadoes. The number of tornadoes is a record for a single day for a non-tropical event in South Texas. All of the tornadoes were weak with the strongest tornado collapsing a grain elevator west of Taft and damaging several homes in a subdivision north of Taft in the evening.||Severe storms started early in the morning in the western Brush Country. Several long track supercell storms moved across the Brush Country and portions of the Coastal Bend during the day. Most of the tornadoes occurred with these storms in the afternoon and early evening. The storms evolved into a large squall line that moved across the Coastal Plains during the evening hours. The squall line produced winds of 70 to 90 mph causing extensive tree damage and localized property damage. The episode of severe weather ended over the Gulf of Mexico after midnight. Damage estimates from the severe weather episode were in the millions of dollars for South Texas.||Several storms moved across the same area for hours during the event. Very heavy rainfall produced flash flooding near Cotulla and in the cities of Kingsville, Beeville, and Freer.

Storm chasers and spotters observed a tornado south of Clegg. The tornado touched down over open ranch country. No damage was observed.

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

9 minutes of warning. NWS CRP issued a tornado warning for this county at 00:05 UTC, 9 minutes before the tornado touched down, in force until 00:45 UTC.

The county was under a tornado watch, issued at 16:43 UTC and running to 00:52 UTC.

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 Storm Prediction Center had this point in a Slight Risk, with a 0.10 chance of a tornado within 25 miles. The outlook in force was issued at 19:54 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 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.

The Corpus Christi radar (KCRP), 83 km away, was scanning. The volume nearest the touchdown began at 00:16 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.

Local storm reports within 60 km of the path, in the three hours either side.

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

The live radar over the trackEvery 2012 tornado in TexasEvery tornado in Texas since 1950Warnings in force in Texas nowThe forecast where you are

18 more were confirmed in the United States that day.

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.

NOAA Storm Prediction Center tornado database, 1950-2025, the official record kept by NOAA's Storm Prediction Center.