Tornadoes · United States · Texas · 2012

EF0 tornado, Runge, Texas, March 20, 2012

This EF0 tornado ran 0.3 miles across Karnes County on March 20, 2012, touching down at 4:05 AM CDT and reaching 30 yards wide. It killed nobody.

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
March 20, 2012
Touchdown
4:05 AM CDT (09:05 UTC)
Lifted
4:06 AM CDT (09:06 UTC)
On the ground
1 minutes
Path length
0.3 miles (0.4 km)
Path width
30 yards (27 m)
Deaths
0
Injuries
0
County
Karnes County
Touchdown point
28.881, -97.718
Lift-off point
28.880, -97.715
Record number
1203200305-01

What the Weather Service recorded

A deep upper level trough of low pressure and strong cold front moved into an area of deep boundary layer moisture. The system initially produced supercell thunderstorms which produced several tornadoes and large hail. There storms then transitioned into a quasi-linear convective system that produced heavy rainfall and flooding.

A small weak EF0 tornado formed along the leading edge of a large cluster of storms in Runge, crossing a few neighborhood streets. Most damage was confined to house roofs, outbuildings, and trees.

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

The warnings

0 minutes of warning. NWS EWX issued a tornado warning for this county at 09:05 UTC, 0 minutes before the tornado touched down, in force until 09:30 UTC.

The county was under a severe thunderstorm watch, issued at 05:53 UTC and running to 10:13 UTC.

Issued (UTC)ExpiredProductOffice
23:00 UTC15:02 UTCFlash Flood WatchEWX
23:25 UTC05:53 UTCTornado WatchEWX
05:53 UTC10:13 UTCSevere Thunderstorm WatchEWX
07:16 UTC09:00 UTCFlood AdvisoryEWX
07:24 UTC10:30 UTCFlash Flood WarningEWX
08:51 UTC12:00 UTCFlash Flood WarningEWX
09:05 UTC09:30 UTCTornado WarningEWX

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. The outlook in force was issued at 04:56 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.

Corpus Christi, TX (KCRP), 00:00Z

9.1 hours before the tornado, 133 km from the path. March 20, 2012.

Skew-T log-pSkew-T log-p diagram, Corpus Christi, TX at 00:00Z on 2012-03-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 2851 joules per kilogram, CIN -113, lifted condensation level 778 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, Corpus Christi, TX at 00:00Z on 2012-03-20The 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 121 square meters per square second, 0 to 6 km bulk shear 40 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
2851 J/kg
Mixed-layer CIN
-113 J/kg
Surface CAPE
3284 J/kg
Mixed-layer LCL
778 m above ground
0-6 km bulk shear
40 kt
0-1 km bulk shear
13 kt
0-1 km storm-relative helicity
121 m²/s²
0-3 km storm-relative helicity
88 m²/s²
Significant tornado parameter
0.6
Supercell composite
3.0
0-3 km lapse rate
5.7 K/km

Open this sounding in Storm Lab

Corpus Christi, TX (KCRP), 12:00Z

2.9 hours after it, 133 km from the path. March 20, 2012.

Skew-T log-pSkew-T log-p diagram, Corpus Christi, TX at 12:00Z on 2012-03-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 20 joules per kilogram, CIN -397, lifted condensation level 439 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, Corpus Christi, TX at 12:00Z on 2012-03-20The 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 97 square meters per square second, 0 to 6 km bulk shear 67 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
20 J/kg
Mixed-layer CIN
-397 J/kg
Surface CAPE
4 J/kg
Mixed-layer LCL
439 m above ground
0-6 km bulk shear
67 kt
0-1 km bulk shear
40 kt
0-1 km storm-relative helicity
97 m²/s²
0-3 km storm-relative helicity
272 m²/s²
Significant tornado parameter
0.0
Supercell composite
6.6
0-3 km lapse rate
3.6 K/km

Open this sounding in Storm Lab

The radar

The Austin/San Antonio radar (KEWX), 96 km away, was scanning. The volume nearest the touchdown began at 09:06 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
08:00 UTCFUNNEL CLOUD5 E RungeDewitt, TXFUNNEL CLOUD SPOTTED BY MEYERSVILLE.
09:00 UTCHAIL 0.52 N CueroDewitt, TXMARBLE SIZE HAIL AND 2.40 INCHES OF RAINFALL.

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

This ground now

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

The other tornadoes of March 20, 2012

3 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
March 2011:36 AM CDTEF0Sabine Parish, LA3.050
March 201:15 PM CDTEF0Winn Parish, LA2.175
March 209:28 PM CDTEF0Natchitoches Parish, LA1.050$60,000

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.