Tornadoes · United States · Nebraska · 2009

EF0 tornado, Mullen, Nebraska, May 12, 2009

This EF0 tornado ran 3.5 miles across Hooker County on May 12, 2009, touching down at 6:21 PM MDT and reaching 10 yards wide. It killed nobody, and did $5,000 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 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 12, 2009
Touchdown
6:21 PM MDT (00:21 UTC)
Lifted
6:32 PM MDT (00:32 UTC)
On the ground
11 minutes
Path length
3.5 miles (5.6 km)
Path width
10 yards (9 m)
Deaths
0
Injuries
0
Property damage
$5,000
County
Hooker County
Touchdown point
41.842, -101.193
Lift-off point
41.825, -101.130
Record number
0905121821-01

What the Weather Service recorded

A supercell thunderstorm produced a tornado and hail during the early evening hours.

Numerous trained storm spotters reported the touchdown of the tornado approximately 17 miles south southwest of Mullen. The tornado traveled across open rangeland until encountering one ranch. As it moved past the ranch, it demolished a metal windbreak, a tower, an outbuilding, and a windmill. The tornado also broke off large trees and carried a pickup cab 100 feet. The tornado then continued on a east-southeast track carrying debris 2 miles. The tornado was on the ground for about 3.5 miles.

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

The warnings

28 minutes of warning. NWS LBF issued a tornado warning for this county at 23:53 UTC, 28 minutes before the tornado touched down, in force until 00:30 UTC.

The county was under a severe thunderstorm watch, issued at 00:10 UTC and running to 05:56 UTC.

Issued (UTC)ExpiredProductOffice
23:53 UTC00:30 UTCTornado WarningLBF
00:10 UTC05:56 UTCSevere Thunderstorm WatchLBF
00:28 UTC01:15 UTCTornado WarningLBF
04:40 UTC05:04 UTCSevere Thunderstorm WarningLBF
15:00 UTC01:00 UTCWind AdvisoryLBF

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, with a 0.02 chance of a tornado within 25 miles. The outlook in force was issued at 20:01 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.

N. Platte/Lee Bi, NE (KLBF), 00:00Z

0.4 hours before the tornado, 91 km from the path. May 13, 2009.

Skew-T log-pSkew-T log-p diagram, N. Platte/Lee Bi, NE at 00:00Z on 2009-05-13Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 276 joules per kilogram, CIN -348, lifted condensation level 1901 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, N. Platte/Lee Bi, NE at 00:00Z on 2009-05-13The 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 57 square meters per square second, 0 to 6 km bulk shear 46 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
276 J/kg
Mixed-layer CIN
-348 J/kg
Surface CAPE
1487 J/kg
Mixed-layer LCL
1901 m above ground
0-6 km bulk shear
46 kt
0-1 km bulk shear
13 kt
0-1 km storm-relative helicity
57 m²/s²
0-3 km storm-relative helicity
177 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0
0-3 km lapse rate
7.1 K/km

Open this sounding in Storm Lab

N. Platte/Lee Bi, NE (KLBF), 12:00Z

11.6 hours after it, 91 km from the path. May 13, 2009.

Skew-T log-pSkew-T log-p diagram, N. Platte/Lee Bi, NE at 12:00Z on 2009-05-13Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel lifted from the surface. Mixed-layer CAPE 0 joules per kilogram, CIN -79471, lifted condensation level 1702 meters above ground. Wind barbs in knots down the right edge.LCL10008507005003002001001 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, N. Platte/Lee Bi, NE at 12:00Z on 2009-05-13The 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 -174 square meters per square second, 0 to 6 km bulk shear 55 knots.1939587897Sfc1 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
0 J/kg
Mixed-layer CIN
-79471 J/kg
Surface CAPE
0 J/kg
Mixed-layer LCL
1702 m above ground
0-6 km bulk shear
55 kt
0-1 km bulk shear
15 kt
0-1 km storm-relative helicity
-174 m²/s²
0-3 km storm-relative helicity
-193 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0
0-3 km lapse rate
3.7 K/km

Open this sounding in Storm Lab

The surface observations

Thedford (TIF), 51 km from the path, in the two hours either side.

Time (UTC)Temp (°F)Dew point (°F)WindGust (kt)Pressure (mb)Weather
22:30 UTC73.451.8180° 18 kt231000
22:50 UTC71.651.8180° 15 kt211000
23:10 UTC69.853.6180° 17 kt20999.7
23:30 UTC69.853.6170° 12 kt22999.7
23:50 UTC69.853.6170° 12 kt999
00:10 UTC69.853.6170° 10 kt15999.3
00:30 UTC6853.640° 3 kt1000.3
00:50 UTC64.455.4300° 8 kt1001.4-VCTSRA
01:10 UTC64.457.2140° 16 kt998.6VCTSRA
01:30 UTC62.657.2160° 13 kt20999-TSRA
01:50 UTC62.657.2150° 13 kt999TS
02:10 UTC64.455.4160° 14 kt999

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

The radar

The North Platte radar (KLNX), 50 km away, was scanning. The volume nearest the touchdown began at 00:21 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
00:17 UTCFUNNEL CLOUD15 S MullenHooker, NEFUNNEL REACHED THREE QUARTERS OF THE WAY TO THE GROUND.
00:21 UTCTORNADO15 S MullenHooker, NEA TORNADOO WAS SPOTTED ON THE GROUND WITH DEBRI VISIBLE.
00:34 UTCHAIL 1.7515 S MullenHooker, NEA FEW QUARTER AND GOLF BALL SIZE HAIL STONES WERE REPORTED IN THE VICINITY OF A DISSIPATED TORNADO NEAR HIGHWAY 97 AND THE DISMAL RIVER.
00:34 UTCTORNADO15 S MullenHooker, NEA TORNADO HAS DISSIPATED 1 MILE WEST OF HIGHWAY 97 AT THE DISMAL RIVER CROSSING.
01:29 UTCTORNADO15 S MullenHooker, NEA TORNADO THAT OCCURED 15 SOUTH OF MULLEN AT 721 PM CDT REPORTEDLY DAMAGED REMOVED A ROOF FROM AN OUT BUILDING AND DAMAGED TWO OTHER STRUCTURES. NUMEROUS TREES AND A RADIO TOWER WERE ALSO DOWNED.
02:30 UTCHAIL 0.2520 N MullenCherry, NEHAIL WAS REPORTED TO BE THE SIZE OF TINY PEBBLES.
02:40 UTCHAIL 0.2519 N MullenCherry, NE

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 NebraskaEvery tornado in Nebraska since 1950Warnings in force in Nebraska nowThe forecast where you are

The other tornadoes of May 12, 2009

3 more were confirmed in the United States that day.

DateTimeRatingWherePath (mi)Width (yd)DeathsInjuriesDamage
May 125:00 PM EDTEF0Polk, FL0.015$15,000
May 125:28 PM MDTEF0Ziebach, SD0.120
May 125:40 PM MDTEF1Ziebach, SD8.2200$100,000

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.