When CO2 levels were lower, July 5th used to be a hot day in the US. As CO2 has increased the frequency of hot weather on July 5th has declined.
The hottest July 5th occurred in 1911, when almost the entire country was over 90 degrees, and 100 degree temperatures stretched from California to new Hampshire.
On July 5, 1936 South Dakota was 120 degrees. Montana was 113 degrees. Nebraska was 112 degrees. North Dakota was 111 degrees, Iowa was 110 degrees. Wyoming was 109 degrees.
I was shooting fireworks early this morning in Wyoming, and it was cold.