October 20 used to be a warm day in the US, but temperatures have plummeted over the past century.
On this date 70 years ago, there were 90-degree temperatures across the Great Plains. North Loup, Nebraska was 98 degrees.
On this date 80 years ago, almost all of the US east of the Rocky Mountains was over 80 degrees, with 90 degrees in Virginia.
Read more at Real Climate Science