A heat dome​ is trapping over 90 million Americans in extreme temperatures this week with the National Weather Service​ issuing heat alerts from Nebraska to Florida.

It’s the hottest time of the year in the United States and another heat dome is about to make millions of people feel every bit of it.

Heat and humidity will once again smother the eastern half of the country this week, pushing the heat index to dangerous levels for tens of millions of people. In the Midwest, the humidity will be ...