Dangerous and potentially deadly heat will settle over the Southwestern United States for the next several days, with temperatures in some locations expected to break records and exceed 110 degrees.

More than 22 million people in California, Nevada and Arizona are under some sort of heat-related alert through at least part of the weekend, the National Weather Service said. A heat wave is defined as a period of abnormally and uncomfortably hot and unusually humid weather that lasts for two or more days.