 Average temperatures were well above normal in the U.S. in June, according to new data released by the National Oceanic and Atmospheric Administration, or NOAA. Overnight temperatures are increasing more rapidly than daytime highs in most of the country, as climate change causes the Earth to heat up. And last month, NOAA estimates that about 24 million people in the West, South, and Northeast experienced the warmest overnight temperatures ever recorded for June.