May 21, 1860 - A swarm of tornadoes occurred in the Ohio Valley. Tornadoes struck the cities of Louisville, KY, Cincinnati, OH, Chillicothe, OH, and Marietta, OH, causing a million dollars damage. (David Ludlum)

May 21, 1895 - The temperature at Norwalk, OH, dipped to 19 degrees to set a state record for the month of May. (The Weather Channel)

May 21, 1896 - The mercury soared to 124 degrees at Salton, CA, to establish a U.S. record for May. (Sandra and TI Richard Sanders - 1987)

May 21, 1980 - The temperature at Williston ND reached 102 degrees to set a record for May, and the next day the mercury hit 106 degrees. (The Weather Channel)

May 21, 1987 - Severe thunderstorms, developing along a sharp cold front crossing the central U.S., produced 60 mph winds and golf ball size hail at Sedalia, MO, and drenched Hagerstown, IN, with six inches of rain in one hour. Temperatures soared into the 90s ahead of the cold front. Paducah, KY, hit 94 degrees for the second day in a row. Light snow blanketed Montana, with three inches reported at Butte. (The National Weather Summary) (Storm Data)

May 21, 1988 - Severe thunderstorms swept across southern Louisiana during the morning hours spawning six tornadoes, and producing wind gusts to 88 mph at Jennings. Thunderstorms also produced five inches of rain in two hours at Lake Charles, causing local flooding. (The National Weather Summary) (Storm Data)

May 21, 1989 - Thunderstorms moving southeastward across the Central Plains Region into Oklahoma and Arkansas produced severe weather through the day and night. Thunderstorms spawned just four tornadoes, but there were 243 reports of large hail and damaging winds. Baseball size hail was reported at Augusta, KS, and thunderstorm winds gusted to 98 mph at Johnson, KS. (The National Weather Summary) (Storm Data)

May 21, 1990 - Thunderstorms produced severe weather across the southeastern U.S. for the second day in a row. Severe thunderstorms spawned five tornadoes, including one which injured a person at Richmond KY. There were eighty-seven reports of large hail or damaging winds, with hail three inches in diameter reported at Austin TX. Thunderstorms produced up to five inches of rain in Macon County GA, and heavy rains left nearly eight feet of water over roads near Stepstone KY. (The National Weather Summary) (Storm Data)