Extreme heat spread across Arizona, New Mexico and parts of Texas, Colorado and Kansas as severe weather swept across many parts of the U.S. on Sunday. There was unseasonable cold in the Pacific Northwest, snow headed to the northern Rocky Mountains and heavy rainfall forecast from the northern Plains to the Upper Midwest.
The National Weather Service estimated that more than 63 million people were under heat advisories on Sunday, stretching from the Southwest northward up through Denver and into Chicago.
