WATERTOWN, S.D. (KWAT)–The National Weather Service has done damage surveys on two tornadoes that touched down in South Dakota on Sunday afternoon.

The first tornado, which was the larger of the two, touched down with documented signs of damage at a farm six miles southeast of Mobridge.

A grain silo was damaged, and a semi trailer was tipped over. As the twister continued to track, it destroyed an entire outbuilding on a farm a mile south of Highway 12.

The weather service says the tornado was on the ground for four miles, and had peak winds estimated at 110 miles an hour. It was rated an EF-1 on the Enhanced Fujita Scale.

The second tornado was spotted by storm chasers over open land eight miles northeast of Wakpala. No damage was reported.