Nearly 160 million people are under heat alerts from eastern Texas to Maine, as temperatures are forecasted to be as much as 20 degrees Fahrenheit above seasonal averages. Highs in the triple digits are possible along the East Coast, with temperatures in New York City and Washington, D.C., rivaling Death Valley in California.

With some extreme heat and humidity ahead, there's also a chance Maine could experience power outages due to the demand for air conditioning across New England.