Widespread 90s, even perhaps a few 100s, will bake much of the eastern two-thirds of the country in a dangerous heat wave. Here's when it will arrive and how long it could stick around.

States in the Midwest and Northeast will face high temperatures in the coming days during the summer’s first “dangerous” heat wave, according to the National Weather Service. An expanding heat wave hitting the Southwest and Rockies will shift by the weekend to produce “the most oppressive heat of the season to date” from the Midwest to the Northeast this weekend and next week,