Some of the highest temperatures on Friday are expected in towns close to the Nebraska-Kansas border, with those in Kansas's St. Francis and Oberlin, and McCook, Nebraska, likely to rise to 105 degrees and over before the end of the day, according to the National Weather Service.

Millions of Americans are facing oppressive heat, with forecasters expecting a "heat dome" to develop over parts of the county over the weekend and through next week. The National Weather Service (NWS) warns that heat related illnesses increase significantly during extreme heat events.

Maps show where extreme humidity and 90- or 100-degree temperatures will affect around 255 million people across the United States.

EDT the National Weather Service released a heat advisory valid from Saturday noon EDT until Sunday 8 p.m. EDT for Emmet, Cheboygan, Presque Isle, Leelanau, Antrim, Otsego, Montmorency, Alpena, Benzie,

An extreme heat watch has been issued for all of Southeast Michigan Saturday morning through Tuesday evening. Expect high temperatures well into the 90s and heat index temperatures at or above 100 degrees during daytime hours.