Record-breaking heat likely for most of the country this week

Summer may officially begin on Thursday, but Mother Nature isn’t waiting around until then. Nearly 84% of the U.S. population will experience temperatures 90 degrees or higher this week.

Notable cities that will experience “Extreme Heat Risk” include Chicago, St. Louis, Indianapolis, Detroit, Cleveland, Cincinnati, Pittsburgh, Philadelphia, New York, Albany and Boston. The heat is expected to last most of the week, potentially the longest duration of heat experienced in decades in some locations.

Extreme Heat is the number one weather killer, resulting in hundreds of deaths each year.. A heat wave is not formally declared until we have three or more straight days of highs in the 90s.

Heat dome

The reason for the heat is thanks to a large ridge of high pressure and the position of the high. With it located along the east coast, the winds in the middle part of the country and Midwest will be out the south and southwest.

This warm fetch of air will bring the heat and humidity on Monday to those locations. As the high shifts further east off the coast of the eastern seaboard, the hot air will move into Ohio River Valley, northeast and New England regions.

Meanwhile, areas located along the outer periphery of the ridge will see daily isolated rain and storm chances. Known as “ridge-rider” storms as the ridge blocks the storms from entering regions dominated by it. 

Tuesday’s highs

The heat moves further east into New England and along the east coast by Tuesday. 

Here are the potential records that could be compromised. 

Wednesday’s heat

The heat looks to be most extreme by Wednesday, putting millions more at “Extreme Heat Risk.”

Here are the records with the best chance of falling on Wednesday. 

Friday will be even hotter for some

The heat dome will shift westward by late week, bringing a return to the upper 90s for the Mississippi River Valley. Temperatures in the 90s look to stick around through the weekend into next week. 

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