USA historic October temperatures
Prior to 1965, October 18 was a very warm day in the US, but after 1965 temperatures plummeted and never recovered.

Historic USA recordings temperatures above 80 degreees
On this date in 1953, almost the entire US east of the Rocky Mountains was over 80F, and much of the southern US was over 90 degrees.
Average temperatures October 18th 1953 USA