Since 1895, the US Midwest has recorded March temperatures above ninety degrees on 65 occasions, spread out over 25 days. All of these occurred more than 30 years ago, and 63 of the 65 hot days occurred at least 90 years ago. The two hottest days were March 27, 1910 and March 24, 1929 – both of which reached 97F (36C.)

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Same story with 85 degree March days – they used to be relatively common, but rarely happen any more.

The table below shows the dates when March ninety degree temperatures were recorded. Note that the Midwest had 90 degree temperatures on eight consecutive days from March 19, 1907 to March 26, 1907.

3/29/1905 3/19/1907 3/20/1907 3/21/1907 3/22/1907 3/23/1907 3/24/1907 3/25/1907 3/26/1907 3/22/1910 3/23/1910 3/24/1910 3/25/1910 3/27/1910 3/28/1910 3/29/1913 3/21/1916 3/30/1917 3/14/1918 3/22/1928 3/23/1929 3/24/1929 3/25/1929 3/24/1967 3/6/1988

On March 24, 1907 there was an ice cream shortage due to the heat, and people blamed the heat on a comet.

25 Mar 1907, Page 6 – The Fort Wayne News at Newspapers.com

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The East coast was also having a record heatwave, and people blamed the heat on sunspots.

24 Mar 1907, Page 11 – The Washington Post at Newspapers.com

30 Mar 1907, Page 2 – The Indianapolis Star at Newspapers.com

The warmest March in the US occurred in 1910.

On March 24, 1910 the average maximum temperature across the US was 74 degrees, and nearly half of the US was above 80 degrees.

Heat like this is inconceivable now, but if it did happen climate experts would declare 99% certainty it was caused by CO2.