The 1936 North American heat wave was one of the most severe heat waves 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 United States 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 as well, 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 records—many of which still stood 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 eight consecutive days from July 7-14, 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.
Some stations in the American Midwest reported minimum temperatures at or above 90 °F (32 °C), such as 91 °F (33 °C) at Lincoln, Nebraska, on July 25, 1936; the next and most recent time this is known to have happened is during a similar, but far less intense, heat wave in late June 1988 that produced a handful of 90 °F (32 °C) minimums. The highest nightly low temperature outside the Desert Southwest was 94 °F (34 °C) at Atchison, Kansas, during the heat wave of July 1934.
August was the warmest month on record for five states. Many experienced long stretches of daily maximum temperatures 100 °F (38 °C) or warmer. Drought conditions worsened in some locations. Other states were only slightly warmer than average.
The heat wave and drought largely ended in September, though many states were still drier and warmer than average. Many farmers' summer harvests were destroyed. Grounds and lawns remained parched. Seasonable temperatures returned in the autumn.
As many as 5,000 heat-related deaths were reported in the United States, and 780 direct and 400 indirect deaths in Canada. Many people suffered from heat stroke and heat exhaustion, particularly the elderly. Unlike today, air conditioning was in the early stages of development and was therefore absent from houses and commercial buildings. Many of the deaths occurred in high-population-density areas of Chicago, Detroit, St. Louis, Milwaukee, Cleveland, Toronto, and other urban areas. Farmers across the continent saw crop failure, causing corn and wheat prices to rise quickly. Droughts and heat waves were common in the 1930s. The 1930s (the Dust Bowl years) are remembered as the driest and warmest decade for the United States, and the summer of 1936 featured the most widespread and destructive heat wave to occur in the Americas in centuries.
The average temperature across the Lower 48 was 77.6 degrees Fahrenheit, 3.3 degrees above the 20th-century average, the National Oceanographic and Atmospheric Administration reported. That edged out the previous high mark, set in 1936, by two-tenths of a degree, NOAA said.
This one was different, though, not only in the number it killed but in the very intensity of the heat. Records for high temperatures set during that summer still stand in 15 states, including Michigan. In Kansas and North Dakota, it reached 121 degrees, marks surpassed in this country only in the deserts of the Southwest.