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.

Tornado in SMITH, KANSAS
From 12-APR-15 17:46:00 to 12-APR-15 17:48:00 (CST-6)
Location: SMITH CENTER
Tornado F-scale: EF0
Property damage: 20.00K
Crop damage: 0.00K
Reported by: NWS Storm Survey

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.

Hail in SMITH, KANSAS
From 12-APR-15 18:10:00 to 12-APR-15 18:17:00 (CST-6)
Location: LEBANON
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in JEWELL, KANSAS
From 12-APR-15 18:39:00 to 12-APR-15 18:39:00 (CST-6)
Location: BURR OAK
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

Hail in JEWELL, KANSAS
From 12-APR-15 18:45:00 to 12-APR-15 19:00:00 (CST-6)
Location: MANKATO
Magnitude: 1.75 
Property damage: 25.00K
Crop damage: 0.00K
Reported by: Social Media

Hail in JEWELL, KANSAS
From 12-APR-15 19:13:00 to 12-APR-15 19:18:00 (CST-6)
Location: FORMOSO
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in SMITH, KANSAS
From 12-APR-15 17:12:00 to 12-APR-15 17:12:00 (CST-6)
Location: KENSINGTON
Magnitude: 0.88 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter