F1 tornado in Pottawatomie County, Oklahoma

This tornado caused structural damage to oil pumping and storage equipment approximately 2 miles southwest of Harjo and structural damage to trailer homes 1 mile west of Harjo. The beginning and ending times of this tornado were listed incorrectly in the original version of storm data. The beginning time should be 0200 CST, while the ending time should be 0206 CST.

Six tornadoes across southern Oklahoma and one tornado across western north Texas developed during the overnight hours of the 11th. The most notable tornado formed across Coal County in Oklahoma and resulted in one fatality and one injury as it destroyed a mobile home. In addition to damage produced by severe thunderstorms, sustained winds of 40 to 50 mph with gusts as high as 73 mph developed just ahead of the most frequent period of severe weather and persisted for several hours. In Tillman County, at 2330 CST on the 10th, a barn roof was damaged 3 miles east of Frederick. A barn roof was blown off, and a fence was downed 4 miles east of Frederick, and a house roof sustained minor damage 4 miles north of Frederick. Trees and power lines were downed in Ponca City in Kay County, while in Garfield County, minor but widespread damage, was sustained to trees, power poles, and numerous other structures.