Omaha's Eppley Airfield recorded the peak rainfall of 10.48 inches during the 24-hour period ending at 4 a.m. Saturday.  The old Omaha 24-hour precipitation record was 7.03 inches and was set back on August 26-27, 1903.  The new Omaha record of 10.48 inches of rain is however still short of the state record for a 24-hour rainfall of 13.15 inches set in York, NE on July 9, 1950.  The original press release listed 10.46 inches but the amount was adjusted upward by the NWS to 10.48 inches on August 12, 1999.

Two radar images, shown below, indicated that the thunderstorms were reaching heights of 55,000 feet and also producing hail in addition to the heavy rains.  The thunderstorms were slow moving and basically forming just southwest of Omaha and moving across the same area for hours.  The two images are taken two hours apart, but the precipitation cells are over the same area.

This is not an unusual time of the year to have heavy precipitation across the region.  Many of the state precipitation records for heaviest 24-hour precipitation have been set in the months of July and August.  Lincoln, NE had its record 24-hour precipitation amount of 8.38 inches occur on August 28-29, 1910 for example.  August usually brings the highest dew point temperatures (and greatest atmospheric moisture content).  August usually also has the slowest moving storm systems which can cause localized flooding as storms slowly move over an area. 

Flooding is the number one weather killer in the U.S.  Check out our web site: U.S. Natural Disaster Fatalities .   And, in keeping with our educational mission, DO NOT DRIVE THROUGH FLOODED ROADWAYS.  It only takes a few inches of rapidly moving water to push a vehicle off the road.