Hail in Sherman County, Nebraska

A deep upper trough moved over the Central Plains. A shortwave moved over east central Colorado during the afternoon and CAPE values were highest just to the east of this feature. Low-level moisture was limited and instability was marginal across south central and central Nebraska but high enough for storms to produce severe updrafts. Wind shear values were around 40 to 50 knots, and a cold front was moving toward the area. Low-level storm relative helicity was increasing which lead to a greater tornado threat.

Thunderstorms developed during the afternoon ahead of the shortwave and became severe across portions of western Kansas and portions of southern Nebraska. These storms continued to develop and move eastward as the afternoon progressed. The storms began by producing nickel sized hail in Furnas County around 3 pm CDT. The hail got up to the size of golf balls in Dawson, Harlan, Phelps, and Adams Counties. A few of the storms produced tornadoes in Dawson and Sherman Counties. These tornadoes resulted in some damage and were rated EF-0. These storms eventually developed into a line as they moved across portions of Nebraska and Kansas. Aside from an estimated 70 mph wind causing some damage a farmstead near Marquette in Hamilton county, the strongest wind gust reported from the line of storms was 86 mph in Polk County. This wind gust along with other wind gusts resulted in wind damage across portions of south central and central Nebraska. The last severe report of the day was just before 7 pm CDT in Polk County with a wind gust near 60 mph.