Thursday marks the 15th anniversary of the most destructive and second deadliest tornado in South Dakota history – the tornado that destroyed the town of Spencer. On May 30th, 1998, it began as a large, dust-cloaked tornado northwest of Farmer. It struck several farmsteads before crossing the Hanson/McCook County line a half mile from Spencer. Mobile Doppler radar data showed winds of up to 246 mph in the tornado that was just above ground level. Spencer has since been rebuilt using a mixture of federal, state, and private money.
Some photos of the tornado can be seen here: http://www.stormeyes.org/tornado/spencer/spenpix.htm