Tornadoes · United States · Alabama · 2012

EF0 tornado, Roxana, Alabama, May 13, 2012

This EF0 tornado ran 2.3 miles across Lee County on May 13, 2012, touching down at 2:02 PM CDT and reaching 50 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
May 13, 2012
Touchdown
2:02 PM CDT (19:02 UTC)
Lifted
2:11 PM CDT (19:11 UTC)
On the ground
9 minutes
Path length
2.3 miles (3.7 km)
Path width
50 yards (46 m)
Deaths
0
Injuries
0
County
Lee County
Touchdown point
32.656, -85.690
Lift-off point
32.677, -85.661
Record number
1205131302-01

The damage survey

4 damage points were recorded along this path by NWS BMX, in the Damage Assessment Toolkit the survey teams carry. The strongest indicator was rated EF0.

  • Small pine tree snapped. Winds estimated 50-60mph. Surveyed by Lee County Emergency Management.
  • Damage to tree branches, including one tree branch downed. Winds estimated 50-60mph. Surveyed by Lee County Emergency Management.
  • Start Point of Roxana EF-0 Tornado. Surveyed by Lee County Emergency Management.
  • End Point of Roxana EF-0 Tornado. Surveyed by Lee County Emergency Management.

Survey points are preliminary and are the raw material the published rating was built from. Source: NWS Damage Assessment Toolkit.

What the Weather Service recorded

A weak cold front moved through Alabama on Sunday, May 13. Shear profiles ahead of and along the front were supportive of supercells. Given the enhanced low level storm relative helicity, numerous, weak mesocyclones and rotating wall clouds developed. One storm resulted in a brief tornado touchdown.

An EF0 tornado with winds of 50-60 MPH touched down just west of County Road 217 southwest of Roxana, causing damage to several trees. The tornado tracked northeastward and crossed County Road 66, where it continued to cause minor tree damage. The tornado dissipated just east of County Road 66.

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

The warnings

2 minutes of warning. NWS BMX issued a tornado warning for this county at 19:00 UTC, 2 minutes before the tornado touched down, in force until 19:20 UTC.

Issued (UTC)ExpiredProductOffice
19:00 UTC19:20 UTCTornado WarningBMX
23:51 UTC01:45 UTCFlood AdvisoryBMX

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 16:30 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.

Birmingham, AL (KBMX), 12:00Z

7.0 hours before the tornado, 118 km from the path. May 13, 2012.

Skew-T log-pSkew-T log-p diagram, Birmingham, AL at 12:00Z on 2012-05-13Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 367 joules per kilogram, CIN -24, lifted condensation level 515 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, Birmingham, AL at 12:00Z on 2012-05-13The 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 168 square meters per square second, 0 to 6 km bulk shear 25 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
367 J/kg
Mixed-layer CIN
-24 J/kg
Surface CAPE
498 J/kg
Mixed-layer LCL
515 m above ground
0-6 km bulk shear
25 kt
0-1 km bulk shear
24 kt
0-1 km storm-relative helicity
168 m²/s²
0-3 km storm-relative helicity
215 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0
0-3 km lapse rate
5.8 K/km

Open this sounding in Storm Lab

Birmingham, AL (KBMX), 00:00Z

5.0 hours after it, 118 km from the path. May 14, 2012.

Skew-T log-pSkew-T log-p diagram, Birmingham, AL at 00:00Z on 2012-05-14Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 599 joules per kilogram, CIN -5, lifted condensation level 975 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, Birmingham, AL at 00:00Z on 2012-05-14The 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 -6 square meters per square second, 0 to 6 km bulk shear 23 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
599 J/kg
Mixed-layer CIN
-5 J/kg
Surface CAPE
2115 J/kg
Mixed-layer LCL
975 m above ground
0-6 km bulk shear
23 kt
0-1 km bulk shear
8 kt
0-1 km storm-relative helicity
-6 m²/s²
0-3 km storm-relative helicity
6 m²/s²
Significant tornado parameter
0.0
Supercell composite
-0.2
0-3 km lapse rate
6.5 K/km

Open this sounding in Storm Lab

The surface observations

Auburn-Opelika Apt (AUO), 23 km from the path, in the two hours either side.

Time (UTC)Temp (°F)Dew point (°F)WindGust (kt)Pressure (mb)Weather
17:15 UTC66.264.4130° 8 kt1017.9
17:35 UTC66.264.4140° 8 kt1017.9
17:55 UTC6866.2140° 6 kt1017.3
18:15 UTC69.866.2130° 9 kt1017.3
18:35 UTC69.866.2120° 7 kt1016.9
18:55 UTC69.866.2150° 7 kt1016.6
19:15 UTC71.666.2140° 7 kt1016.3
19:35 UTC71.666.2120° 7 kt1015.9
19:55 UTC69.866.2120° 4 kt1015.9
20:15 UTC69.866.280° 5 kt1015.6
20:35 UTC69.868160° 11 kt1015.2VCTS
20:55 UTC71.668140° 5 kt1015.6

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

What was reported nearby

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

Time (UTC)ReportWhereCountyRemark
19:02 UTCTORNADO 02 Ssw RoxanaLee, ALTHE TORNADO TOUCHED DOWN JUST WEST OF COUNTY ROAD 217 AND CROSSED THE ROAD WHERE IT DID DAMAGE TO TREE BRANCHES INCLUDING ONE DOWNED TREE BRANCH. THE TORNADO CONTINUED 2.1 MILES TO THE NORTHEAST AND CROSSED COUNTY ROAD 6

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 AlabamaEvery tornado in Alabama since 1950Warnings in force in Alabama nowThe forecast where you are

The other tornadoes of May 13, 2012

1 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
May 131:49 PM MDTEF1Socorro, NM1.275$1,000

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.