• 1934: Pierre recorded a high temperature of 103 degrees. This is the earliest, yearly date the city of Pierre reached 100 degrees. Mobridge also reached 103 degrees, which is the earliest yearly date for the city Mobridge.
• 1986: Thunderstorms produced very heavy rainfall of two to four inches over much of central and eastern South Dakota. The very heavy rainfall caused extensive flooding with Walworth and Potter Counties reporting the most damage. In those counties, most roads were under water. Several bridges and roads were also washed out in that area. The heavy rain washed out the dam at Lake Byre in Lyman County which produced water waist deep in Kennebec. The city of Kennebec lost their sole source of water when the dam broke. Cow Creek in Lyman County also flooded and broke a part of a dam, causing minor property damage. Rain continued to fall into the morning hours on the 9th. Some two day rainfall totals include; 4.33 inches in Kennebec; 4.21 in Shelby; 3.91 at 4 miles west of Mellette; 3.30 in Gettysburg; 3.06 in Blunt; 2.99 in Eureka; 2.75 at 2 NNW of Mobridge; 2.70 inches 2 miles south of Ashton and in Britton.
• 1995: Flooding caused by snowmelt from two significant snowstorms in April continued throughout May. The flooding was aggravated by widespread heavy rains, especially from the early morning of the 8th through the early morning of the 9th. Rainfall amounts generally ranged from one to four inches. Some higher rainfall amounts include; 5.50 inches at Wakpala, 4.50 at Chelsea and Leola, 4.20 at Ipswich, 4.10 inches 12 north of McLaughlin, and 3.91 inches at Aberdeen. A worker was injured near Claremont when the train derailed due to the weakening of the rail-bed caused by high water. The extensive flooding continued to cause road damage and many road closures.
• 1784: Eight people were killed in what may have been the U.S.'s deadliest hailstorm. Hail nine inches in circumference also killed sheep and birds when it fell along the Wateree River in South Carolina.
• 1895: A light rain shower in Winnipeg dropped a mixture of rain and black ants on the city. Most of the black ants were the size of huge wasps.
• 1965: A mile-wide F5 tornado swept farms clean along a 30-mile path near Colome, SD. The tornado traveled in nearly a due north direction. Fortunately there were no fatalities.
• 1981: Dallas/Fort Worth was hit by one of their worst hailstorms on record, as baseball to grapefruit sized hail and 100 mph winds caused $200 million in damages. The hail actually accumulated 8 inches deep in Cedar Hill, TX.
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