On this date in 1930, Washington DC reached 106F – the hottest temperature ever recorded there. Most of the eastern half of the US was above 100F.
The closest USHCN station to DC in Virginia is at Lincoln. It is close to where I stay when I am in Maryland. They had nineteen days over 100F in 1930, and eighteen in 1931. One hundred degree days were much more common in the DC area prior to 1960, and have become less frequent as atmospheric CO2 has increased.
Things have changed though. The Washington Post now believes that temperatures ranging from 86 degrees to 98 degrees are “serious triple-digit heat.” Apparently math isn’t their strongest skill.