EF0 tornado, Smith Center, Kansas, April 12, 2015

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.

Rating

EF0

Date

April 12, 2015

Touchdown

6:46 PM CDT (23:46 UTC)

Lifted

6:48 PM CDT (23:48 UTC)

On the ground

2 minutes

Path length

1.1 miles (1.8 km)

Path width

20 yards (18 m)

Deaths

0

Injuries

0

Property damage

$20,000

County

Smith County

Touchdown point

39.825, -98.784

Lift-off point

39.819, -98.764

Record number

1504121746-01

1 damage points were recorded along this path by NWS GID, in the Damage Assessment Toolkit the survey teams carry. The strongest indicator was rated EF0. The highest wind the damage implies is 75 mph.

• roof peeled back on NE side. Brief Touchdown in area. No discerbable path. Width 15 yards.

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

Between 6-9 p.m. CDT on this late Sunday afternoon and evening, a fairly compact-but-intense supercell storm tracked eastward across mainly central sections of Smith and Jewell counties. This storm yielded several reports of large hail and also the first tornado of 2015 within this six-county North Central Kansas area, an EF-0 that touched down three miles north of Smith Center and tracked for about one mile, damaging the roof of an outbuilding. Prior to this brief tornado, there had been several reports of a funnel cloud or multiple funnels as the storm traversed west-central Smith County. For most of its path, this supercell was primarily a hail-producer, as quarter size stones fell in Lebanon, Burr Oak and Formoso, and larger stones up to golf ball size rained down on Mankato for several minutes. ||Focusing on event timing, this storm initiated over the Smith-Phillips County line around 6 p.m. CDT, just ahead of an approaching cold front. At first, it appeared storm mode might assume a southwest-northeast oriented line segment, but a more discrete supercell structure quickly evolved as it tracked east down the Highway 36 corridor. As this storm reached eastern Jewell County around 8 p.m. CDT, it began morphing into a more linear structure that expanded southwestward into Mitchell County for a time. However, there were no further severe weather reports as all thunderstorms exited the local area by 930 p.m. CDT, in tandem with the passing cold front. In the mid-upper levels, forcing was provided by the southern reaches of a broad shortwave trough tracking east across the Central and especially Northern Plains, with this trough ushering in increasing west-southwest flow aloft. At the surface, the well-defined, northeast-southwest oriented cold front steadily swept through North Central Kansas during the evening. Ahead of this boundary, afternoon temperatures across most of the local area topped out between 75-80 F as dewpoints rose into the mid-upper 50s on gusty south winds. The presence of a weak surface low and attendant warm front in the immediate area likely contributed to tornado development, as local surface observations revealed a backing of wind direction to southeasterly ahead of the storm. As for basic severe weather parameters, mixed-layer CAPE values peaked in the 1000-1500 J/kg range in the presence of 0-6 kilometer deep layer wind shear of 40-50 knots.

An EF-0 rated tornado occurred north-northeast of Smith Center, KS. Damage was mainly limited to minor roof damage on an outbuilding, and the path was most likely intermittent. Maximum wind speed was estimated at 75 mph. A combination of radar data, storm survey, photos, and personal accounts were used to determine the approximate location and time of the tornado.

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

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.

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 Storm Prediction Center had this point in a Marginal Risk. The outlook in force was issued at 20:00 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 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.

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

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

The live radar over the trackEvery 2015 tornado in KansasEvery tornado in Kansas since 1950Warnings in force in Kansas nowThe forecast where you are

1 more were confirmed in the United States that day.

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.

NOAA Storm Prediction Center tornado database, 1950-2025, the official record kept by NOAA's Storm Prediction Center.