The EPA graph below is based on NOAA adjusted data, and shows that the area of the US affected by hot summer temperatures has increased to record levels.
Actual thermometer data shows the exact opposite. The percentage of US stations to reach 100F has plummeted since the 1930’s. This metric should not be affected by any of the published USHCN adjustments.
The frequency of 100 degree days has also plummeted.
The EPA’s own data shows that heatwaves were much worse in the 1930’s.
The bogus top graph is the result of people tampering with data, and then actually believing the bogus data they generated. The NOAA Climate Extremes Index is junk science.