The Storm Data entry for the date states that approximately 20 funnel clouds were reported in this area and 8 “touched down”. There is a chance that more than 9 South Dakota tornadoes developed on this day but knowing where they began and ended can’t be determined.
An EF4 tornado with estimated wind speeds of 170-175 mph traveled close to 9 miles across parts of Wood and Ottawa Counties in Ohio on June 5, 2010.
A very strong, long-track tornado made it ways through parts of Hampden and Worcester Counties, Massachusetts on June 1, 2011. The path length was just shy of 38 miles and the width grew to a half mile. Per the NWS survey, the estimated max wind speed was 160 mph.