July 14, 1936 was the hottest day on record in the US, with an average maximum temperature of 96F. It was also the hottest day on record in Indiana (116F.)
California, Arizona, Illinois, Indiana, Iowa, Nebraska, Wisconsin, Missouri, Oklahoma, Kansas, Minnesota, and Ohio were over 110 degrees. Thirty states were over 100F and 46 states were over 90F.
“DETROIT, July 13—(AP)—Michigan, sweltering in a heat wave more prolonged than any in its history, counted 365 deaths tonight attributed directly or indirectly to the six-day siege of 100- degree weather.
In the Detroit area 108 deaths were reported in a 14-hour period, 23 of them at Eloise County hospital as the mercury rose to 101 degrees, Out-state the highest mark reported was at Saginaw, where a reading of 111 degrees at 3:40 PM established a new all-time high for the state. The previous record was 110 at Bay City, July 2, 1911”
14 Jul 1936, Page 1 – The Greenville News at Newspapers.com
July 14, 1954 was almost as hot. It was the hottest day on record in Illinois (117F) and Missouri (118F.) Kansas was 120F, Oklahoma, Missouri, Illinois, Arkansas, California, Nebraska and Arizona were over 110F. Thirty-four states were over 100F and forty-six states were over 90F.
