CHICAGO (AP) – High temperatures and humidity will bake much of the central U.S. this week, sending heat indexes soaring as high as 115 degrees in some places for the first time this year.

The National Weather Service says the high pressure system, sometimes called a “heat dome,” will push conditions to their hottest point this summer, though temperatures will stay short of records. Authorities from Minnesota to Louisiana are warning people to take precautions and check on the elderly and other vulnerable neighbors and relatives.

Officials blamed heat for the death last week of an elderly woman in St. Louis County, Missouri. In Illinois, a 4-year-old girl was hospitalized Tuesday after being found unresponsive in a hot vehicle in a northwest Chicago suburb. Details on her condition have not been released.