Ninety-five degree temperatures were common in the Midwest during May prior to 1940, but almost never happen any more. May afternoon temperatures have been declining in the Midwest since the 19th century. The hottest May (by far) was 1934, when 100 degree temperatures were widespread across the Midwest, including 101 degrees at Algona, Iowa on May 7th, 1934.
By May 30th, 1934 – the Midwest was seeing temperatures of 109 degrees.
