June 20, 1956:
An F2 tornado moved ENE from near Rockham to near Athol and Ashton. One person was killed as a mobile home was destroyed near the start of the path. Four barns were destroyed and one home was unroofed. Also on this day, an F5 tornado cut a swath through Fargo, North Dakota killing 10 and injuring at least 103 people.
June 20 1968:
A line of severe thunderstorms moved rapidly, about 60 mph, across the state with winds of up to 100 mph or more. Many areas received extensive hail damage with one and a half inch hail common, although larger sizes up to three inches were reported. Many barns and silos along with other farm buildings were damaged or destroyed. Widespread tree damage occurred, along with extensive damage to utility lines. A number of tornadoes were sighted. This storm probably caused the most extensive damage, of any that has occurred in the state, up to this date. Overall damage was estimated from 10 to 15 million dollars.
June 20, 1991:
Thunderstorms continued to dump additional rain over an already saturated northeastern South Dakota. The worst flooding occurred in Watertown, where between 9 to 12 inches of rain fell during the month of June. The Sioux River overflowed its banks in Watertown, and many houses became surrounded by water. Pastures became flooded, and several head of livestock were lost. Flood water also swept across areas east of Verblen.
June 20, 1997:
Several supercell thunderstorms moved southeast along a strong warm front across far southern Stanley, Jones, far southern Hughes, Lyman, and Buffalo counties through the early morning hours of the 20th producing. Hail up to the size of baseballs and winds gusting to 80 mph damaged and destroyed thousands of acres of crops, broke windows in homes, buildings, vehicles, damaged roofs, and downed many trees. The most extensive crop, building, and tree damage was to farms and ranches around the areas of Draper, Vivian, Presho, and Kennebec where there was a 20 mile long and a 4 mile wide path of destruction.
|Record Highs:||Record Lows:|
|Aberdeen: 101 (1988)||Aberdeen: 34 (1969)|
|Kennebec: 107 (1974)||Kennebec: 36 (1969)|
|Mobridge: 104 (1911)||Mobridge: 37 (1969)|
|Pierre: 105 (1974)||Pierre: 40 (1972)|
|Sisseton: 95 (1989)||Sisseton: 39 (1969)|
|Timber Lake: 100 (1974)||Timber Lake: 33 (1969)|
|Watertown: 99 (1988)||Watertown: 34 (1969)|
|Wheaton: 99 (1988)||Wheaton: 36 (1969)|
|Aberdeen: 1.36" (1975)|
|Kennebec: 1.26" (1901)|
|Mobridge: 1.93" (1968)|
|Pierre: 2.89" (2011)|
|Sisseton: 1.60" (1991)|
|Timber Lake: 1.20" (1987)|
|Watertown: 3.10" (2012)|
|Wheaton: 2.66" (1991)|