Tornadoes · United States · Texas · 2011

EF0 tornado, Thomas, Texas, April 30, 2011

This EF0 tornado ran 2.2 miles across Upshur County on April 30, 2011, touching down at 8:26 PM CDT and reaching 75 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
April 30, 2011
Touchdown
8:26 PM CDT (01:26 UTC)
Lifted
8:30 PM CDT (01:30 UTC)
On the ground
4 minutes
Path length
2.2 miles (3.6 km)
Path width
75 yards (69 m)
Deaths
0
Injuries
0
County
Upshur County
Touchdown point
32.860, -95.050
Lift-off point
32.870, -95.014
Record number
1104301926-01

What the Weather Service recorded

A moderately unstable warm sector developed during the late afternoon and evening hours across Northeast Texas, Southeast Oklahoma and Southwest Arkansas on April 30th. A cold front was present across this region and storms began initiating along this boundary. Shear was sufficient in the lower and mid levels of the atmosphere for a few of these storms to take on supercell characteristics. A few of these storms produced tornadoes, along with large hail and damaging thunderstorm wind gusts.

The National Weather Service conducted a storm survey in northwest Upshur County and concluded that the damage was the result of an EF0 tornado. The tornado first touched down to the east of Simpsonville, Tx. The storm continued on an east northeast track crossing Wolverine Road and lifted near FM 2454. Damage consisted mostly of trees snapped and/or uprooted especially along the end of the track where damage included Rear Flank Downdraft and Inflow damage. Estimated wind speeds were 75-80 mph.

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

The warnings

0 minutes of warning. NWS SHV issued a tornado warning for this county at 01:26 UTC, 0 minutes before the tornado touched down, in force until 02:15 UTC.

The county was under a tornado watch, issued at 22:56 UTC and running to 07:00 UTC.

Issued (UTC)ExpiredProductOffice
22:56 UTC07:00 UTCTornado WatchSHV
00:44 UTC01:45 UTCSevere Thunderstorm WarningSHV
01:26 UTC02:15 UTCTornado WarningSHV
02:02 UTC02:25 UTCTornado WarningSHV
09:47 UTC13:52 UTCTornado WatchSHV
13:52 UTC17:49 UTCSevere Thunderstorm WatchSHV
17:49 UTC02:00 UTCTornado WatchSHV

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 0.05 chance of a tornado within 25 miles. The outlook in force was issued at 00:51 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.

Shreveport, LA (KSHV), 00:00Z

1.4 hours before the tornado, 127 km from the path. May 1, 2011.

Skew-T log-pSkew-T log-p diagram, Shreveport, LA at 00:00Z on 2011-05-01Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 3108 joules per kilogram, CIN -7, lifted condensation level 891 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, Shreveport, LA at 00:00Z on 2011-05-01The 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 170 square meters per square second, 0 to 6 km bulk shear 32 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
3108 J/kg
Mixed-layer CIN
-7 J/kg
Surface CAPE
3951 J/kg
Mixed-layer LCL
891 m above ground
0-6 km bulk shear
32 kt
0-1 km bulk shear
18 kt
0-1 km storm-relative helicity
170 m²/s²
0-3 km storm-relative helicity
199 m²/s²
Significant tornado parameter
2.3
Supercell composite
13.1
0-3 km lapse rate
6.2 K/km

Open this sounding in Storm Lab

Shreveport, LA (KSHV), 12:00Z

10.6 hours after it, 127 km from the path. May 1, 2011.

Skew-T log-pSkew-T log-p diagram, Shreveport, LA at 12:00Z on 2011-05-01Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 2344 joules per kilogram, CIN -1, lifted condensation level 499 meters above ground. Wind barbs in knots down the right edge.LCLEL10008507005003002001001 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, Shreveport, LA at 12:00Z on 2011-05-01The 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 277 square meters per square second, 0 to 6 km bulk shear 52 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
2344 J/kg
Mixed-layer CIN
-1 J/kg
Surface CAPE
2022 J/kg
Mixed-layer LCL
499 m above ground
0-6 km bulk shear
52 kt
0-1 km bulk shear
29 kt
0-1 km storm-relative helicity
277 m²/s²
0-3 km storm-relative helicity
370 m²/s²
Significant tornado parameter
4.9
Supercell composite
18.4
0-3 km lapse rate
5.3 K/km

Open this sounding in Storm Lab

The radar

The Shreveport radar (KSHV), 121 km away, was scanning. The volume nearest the touchdown began at 01:24 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
00:06 UTCTORNADO6 Ene MineolaWood, TXAN EF0 TORNADO TOUCHED DOWN WEST OF HAINESVILLE. TREES WERE SNAPPED WITH A PATH WIDTH OF 50-75 YARDS WIDE. THE STORM CONTINUED ON AN EAST NORTHEAST TRACK CROSSING FM 49 BEFORE LIFTING JUST WEST OF HAINESVILLE. DAMAGE CON
01:10 UTCTSTM WND DMG11 Nw GilmerUpshur, TXMETAL CARPORT WAS LIFTED OFF THE GROUND AND DAMAGED
01:26 UTCTORNADO11 Nw GilmerUpshur, TXAN EF0 TORNADO TOUCHED DOWN EAST OF THE SIMPSONVILLE COMMUNITY. THE STORM CONTINUED ON AN EAST NORTHEAST TRAJECTORY CROSSING WOLVERINE ROAD AND LIFTED NEAR FM 2454. DAMAGE CONSISTED MOSTLY OF TREES SNAPPED AND/OR UPROOTE
01:29 UTCTSTM WND DMG6 Nw GilmerUpshur, TXTREES DOWN AT CR 2088 AND COYOTE ROAD
02:09 UTCTORNADOLone StarMorris, TXTREES AND POWER LINES DOWN ON THE NORTH SIDE OF LONE STAR. POWER OUTAGES REPORTED IN LONE STAR.
02:10 UTCTSTM WND DMG2 S DaingerfieldMorris, TXSTORM SURVEY CONDUCTED IN SOUTHERN MORRIS COUNTY DETERMINED THAT DAMAGE WAS CONSISTENT WITH SEVERE THUNDERSTORM WIND GUSTS NEAR 80 MPH. DAMAGE WAS VERY SPORADIC AND A TORNADO TRACK COULD NOT BE FOUND. NEARLY THE ENTIRE R
02:24 UTCTORNADO1 Sw Hughes SpringsCass, TXAN EF0 TORNADO TOUCHED DOWN ON THE SOUTHWEST SIDE OF HUGHES SPRINGS. SEVERAL TREES WERE SNAPPED NEAR FM 250. TREES WERE DOWNED ONTO POWERLINES AND SHINGLES REMOVED FROM A HOME ALONG FM 2984. ANOTHER BUSINESS HAD ITS SHIN
02:25 UTCTORNADO2 S DaingerfieldMorris, TXTORNADO ON GROUND MOVING NE AT 25 MPH.
02:25 UTCTORNADOHughes SpringsCass, TXSTATE TROOPER REPORTS TORNADO ON THE GROUND AND GOLF BALL SIZED HAIL
02:34 UTCFUNNEL CLOUD2 Ne Hughes SpringsCass, TXSTATE TROOPER REPORTS FUNNEL CLOUD 2 MILES NORTHEAST OF HUGHES SPRINGS

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

This ground now

The live radar over the trackEvery 2011 tornado in TexasEvery tornado in Texas since 1950Warnings in force in Texas nowThe forecast where you are

The other tornadoes of April 30, 2011

2 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
April 307:06 PM CDTEF0Wood, TX1.875
April 309:24 PM CDTEF0Cass, TX2.6150$5,000

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.