The 1936 North American heat wave was the most severe heat wave in the modern history of North America. It took place in the middle of the Great Depression and Dust Bowl of the 1930s, and caused catastrophic human suffering and an enormous economic toll. The death toll exceeded 5,000, and huge numbers of crops were destroyed by the heat and lack of moisture. Many state and city record high temperatures set during the 1936 heat wave stood until the Summer 2012 North American heat wave. The 1936 heat wave followed one of the coldest winters on record.
The heat wave started in late June, when temperatures across the US exceeded 100 °F (38 °C). The Midwest experienced some of the highest June temperatures on record. Drought conditions worsened. In the Northeast, temperatures climbed to the mid 90s °F (around 35 °C). The South and West started to heat up also, and also experienced drought. The heat wave began to extend into Canada. Moderate to extreme drought covered the entire continent. The dry and exposed soil contributed directly to the heat as happens normally in desert areas as the extreme heat entered the air by radiation and direct contact.
July was the peak month, in which temperatures reached all-time record levels—many of which still stand as of 2012. In Steele, North Dakota, temperatures reached 121 °F (49 °C), which remains North Dakota's record. In Ohio, temperatures reached 110 °F (43 °C), which nearly tied the previous record set in 1934. The states of Texas, Oklahoma, Kansas, Arkansas, Minnesota, Michigan, North Dakota, South Dakota, Pennsylvania, Louisiana, Nebraska, Wisconsin, West Virginia, and New Jersey also experienced record high temperatures. The provinces of Ontario and Manitoba set still-standing record highs above 110 °F (43 °C). Chicago Midway airport recorded 100 °F (38 °C) or higher temperatures on 12 consecutive days from July 6–17, 1936. Later that summer in downstate Illinois, at Mount Vernon the temperature surpassed 100 °F (38 °C) for 18 days running from August 12–29, 1936.