Tornadoes · United States · Texas · 2009

EF1 tornado, Corsicana, Texas, April 27, 2009

This EF1 tornado ran 0.6 miles across Navarro County on April 27, 2009, touching down at 8:30 AM CDT and reaching 67 yards wide. It killed nobody and injured 1, and did $100,000 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 mph

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

  2. EF186 to 110 mphthis tornado

    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
EF1
Date
April 27, 2009
Touchdown
8:30 AM CDT (13:30 UTC)
Lifted
8:32 AM CDT (13:32 UTC)
On the ground
2 minutes
Path length
0.6 miles (0.9 km)
Path width
67 yards (61 m)
Deaths
0
Injuries
1
Property damage
$100,000
County
Navarro County
Touchdown point
32.084, -96.487
Lift-off point
32.084, -96.478
Record number
0904270730-01

What the Weather Service recorded

A slow moving squall line produced copious amounts of rainfall and severe weather along and south of Interstate 20. An EF-1 tornado damaged 10 buildings in Corsicana including a school.

An NWS Storm Damage Survey confirmed an EF-1 tornado damaged 10 structures in the west-central portions of Corsicana. Part of the roof was removed from the Lee Academy on West 4th Avenue. On the same street, crepe myrtle and pecan trees were uprooted. Other buildings damaged included the Sonic and Shell Food Mart. Additional trees and large tree limbs were down along the path of the tornado and damage was also sustained to fences, awnings and power poles. Maximum winds were estimated to be 90 mph. One teacher at Lee Academy sustained minor injuries.

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

The warnings

No tornado warning for this county appears in the archive as in force at the moment the tornado touched down. One was issued for the county at another hour that day.

The county was under a tornado watch, issued at 11:11 UTC and running to 18:00 UTC.

Issued (UTC)ExpiredProductOffice
11:11 UTC18:00 UTCTornado WatchFWD
12:57 UTC14:15 UTCSevere Thunderstorm WarningFWD
13:38 UTC14:30 UTCTornado WarningFWD
14:15 UTC17:15 UTCFlood AdvisoryFWD

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 12:59 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.

Fort Worth, TX (KFWD), 12:00Z

1.5 hours before the tornado, 112 km from the path. April 27, 2009.

Skew-T log-pSkew-T log-p diagram, Fort Worth, TX at 12:00Z on 2009-04-27Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 2160 joules per kilogram, CIN 0, lifted condensation level 513 meters above ground. Wind barbs in knots down the right edge.LCLEL10008507005003002001001 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, Fort Worth, TX at 12:00Z on 2009-04-27The 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 79 square meters per square second, 0 to 6 km bulk shear 20 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
2160 J/kg
Mixed-layer CIN
0 J/kg
Surface CAPE
2199 J/kg
Mixed-layer LCL
513 m above ground
0-6 km bulk shear
20 kt
0-1 km bulk shear
26 kt
0-1 km storm-relative helicity
79 m²/s²
0-3 km storm-relative helicity
315 m²/s²
Significant tornado parameter
0.0
Supercell composite
6.5
0-3 km lapse rate
6.2 K/km

Open this sounding in Storm Lab

Fort Worth, TX (KFWD), 00:00Z

10.5 hours after it, 112 km from the path. April 28, 2009.

Skew-T log-pSkew-T log-p diagram, Fort Worth, TX at 00:00Z on 2009-04-28Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 5 joules per kilogram, CIN -561, lifted condensation level 1331 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, Fort Worth, TX at 00:00Z on 2009-04-28The 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 -30 square meters per square second, 0 to 6 km bulk shear 27 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
5 J/kg
Mixed-layer CIN
-561 J/kg
Surface CAPE
59 J/kg
Mixed-layer LCL
1331 m above ground
0-6 km bulk shear
27 kt
0-1 km bulk shear
16 kt
0-1 km storm-relative helicity
-30 m²/s²
0-3 km storm-relative helicity
-54 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0
0-3 km lapse rate
4.1 K/km

Open this sounding in Storm Lab

The radar

The Dallas/Ft Worth radar (KFWS), 94 km away, was scanning. The volume nearest the touchdown began at 13:28 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
13:30 UTCTORNADO1 W CorsicanaNavarro, TXNWS SURVEY TEAM DETERMINED AN EF 1 TORNADO IN WEST-CENTRAL CORSICANA.
13:47 UTCTSTM WND DMGCorsicanaNavarro, TXPART OF ROOF BLOWN OFF...TREE LIMBS DOWN NEAR CENTER OF TOWN
14:05 UTCTSTM WND DMGKempKaufman, TXTIME ESTIMATED...TREES DOWN AT KEMP SCHOOL.

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

This ground now

The live radar over the trackEvery 2009 tornado in TexasEvery tornado in Texas since 1950Warnings in force in Texas nowThe forecast where you are

The other tornadoes of April 27, 2009

6 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
April 274:10 AM CDTEF1Williamson, TX2.150$1.0 million
April 279:28 AM CDTEF0Van Zandt, TX0.820
April 273:36 PM CDTEF0DeWitt, TX0.110$50,000
April 276:11 PM CDTEF1Johnson, AR3.1180$50,000
April 279:25 PM CDTEF0Newton, TX0.010$1,000
April 279:29 PM CDTEF0Jasper, TX0.010

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.