The National Weather Service has rated the tornado that moved through central Ogle County Saturday night as an EF-1, with peak winds estimated at 100mph. The tornado touched down two miles east of Oregon around 9:13pm and was on the ground for 7 miles as it traveled to the northeast, just before lifting southwest of Stillman Valley around 9:24pm.
The tornado traveled mostly over rural areas damaging trees and power lines, but did damage a few outbuildings and barns. This tornado originated from a severe storm that had produced several tornadoes earlier in the evening across western Illinois, before moving into Whiteside County and producing an EF-1 tornado southwest of Tampico. A Tornado Warning was issued for Whiteside County around 8:30pm Saturday evening, and then for Lee and Ogle counties shortly before 9pm. The warning was then extended into Winnebago County and included the city of Rockford, however, the stronger rotation of the storm just passed southeast of the downtown area. Rotation continued to weaken allowing the tornado warning to expire at 9:45pm. No damage was reported in Winnebago County.