Thunderstorm Wind in Nance County, Nebraska

Wind gusts estimated to be near 70 MPH resulted in flipped irrigation pivots in eastern Nance County.

Intense upper level low pressure brings arc of severe thunderstorms to portions of south central Nebraska during the afternoon hours of May 12th. A closed upper low pressure system over SW Nebraska lead to the development of a broken arc of mini-supercells, beginning around 1300-1400CDT. While most of south central Nebraska was in the dry slot of the storm system during the daytime hours, far north and northeastern portions of the CWA remained in the warm sector long enough to develop sufficient instability for strong to severe thunderstorms. The intense nature of the upper low, combined with significantly backed low level winds (and thus high storm relative helicity) lead to development of several low topped supercells that arched from the Nebraska Sandhills, ESE to near Ord and Columbus. A few hail and wind damage reports were received with this activity, but by far the most attention-grabbing portion of the event was a tornado in Greeley County. Damage was very limited with this tornado as it tracked over primarily pasture land in central Greeley County. However, this tornado had high notoriety, regionally and nationally, due to it's highly photogenic nature (well defined tornado in foreground and blue skies in the background), as well as proximity to several well known storm chasers. This was a relatively short-lived event, overall, with all of the severe activity occurring between 1300-1700CDT.