A small but intense tornado outbreak occurred predominantly over McPherson and Brown County, South Dakota on June 23, 2002. A supercell thunderstorm produced six tornadoes in 72 minutes within the two counties. Two of the tornadoes were rated F3 and F4 respectively, and caused considerable damage to several homes and farms. Two other tornadoes occurred in North Dakota during the same time. The outbreak in Brown County was documented by a group of storm chasers and was featured on an episode of The Weather Channel's Storm Stories.
The area hit by the outbreak was in a drought; in the past three months, the area had only received four inches of rain. On June 23, a triple point was set up across eastern South Dakota, setting the stage for a powerful supercell to form.