Much of the Central and Eastern United States experienced record warmth for mid-October due to heat and humidity associated with an expansive high pressure weather system that stretched from Bermuda over the eastern US as well as from winds in the upper atmosphere that drew heat up from the South.

One of the clearest findings of climate science is that global warming has already dramatically amplified the intensity, duration and frequency of extreme heat events. Due to global warming, the most extreme heat events now impact a global area 10 times greater than before. And the impact on moderate heat waves is also dramatic, with a seventy-five percent share of moderate heat events globally now attributed to climate change.