Prior to 1960, August 1 was typically a very hot day in the US with about half of the US over 90 degrees. Since 1960, the percentage of the US over 90 degrees on August 1 has dropped to about 40%.
On August 1, 1955 every state was over 90 degrees, and twenty states recorded temperatures over 100 degrees. (AZ CA CO IA ID KS MN MO MT ND NE NJ NV NY OK SD TX UT VA WY)
via The Deplorable Climate Science Blog
August 1, 2017 at 11:17AM
Iowa Climate Science Education 