Meteorologists from the National Weather Service in North Platte conducted a damage survey in Ainsworth following the significant thunderstorm that occurred Monday afternoon, August 30th, 2010. They determined that the damage in the Ainsworth area was the result of straight line winds associated with a phenomenon known as a wet microburst. Microbursts are small and concentrated downbursts of wind that form as air rapidly rushes out of a thunderstorm and impacts the ground. Wet microbursts are accompanied by heavy rain that drives the downdraft of wind to the surface. Up to 1.6 inches of rain fell in Ainsworth in only 15 minutes. Photographs of the storm over Ainsworth showed a large and circular rain shield that is indicative of a wet microburst. Estimates from the public, law enforcement, and other officials estimated that the winds that caused the damage were between 60 and 80 mph.
The storm hit Ainsworth about 4:40 p.m. CDT Monday afternoon. Damage was significant and included the destruction of two buildings and many trees. Power lines were also downed by the winds and resulted in a power outage that lasted about two hours. The damage was most severe in a relatively concentrated zone, on the north side of the town, which is consistent with a microburst damage path. It was in that area where one of the buildings was destroyed. Debris from the steel building was scattered to the north up to 200 yards, and steel was twisted violently around trees north of the building site.
The Ainsworth storm was just one part of a significant wind damage event that occurred over western and north central Nebraska on August 30th. For a summary of the whole event, click here.