As dangerous heat continues to threaten residents of major U.S. cities, some are more vulnerable to the persisting conditions than others.
While the Centers for Disease Control and Prevention (CDC) reports that more than 600 people are killed by extreme heat in the U.S. every year, The Associated Press says heat contributes to some 1,500 deaths each year, with advocates estimating that about half of those killed are homeless.
It noted that excessive heat causes more weather-related deaths in America than hurricanes, flooding and tornadoes combined.
This year's summer heat has already claimed the life of a 5-year-old Texas boy, who died Monday after being left inside a vehicle for two-to-three hours amid nearly triple-digit temperatures.
Millions of Americans are being advised to keep cool and stay hydrated and advisories stretch across the U.S.
Humidity in many areas will increase "feels-like" temperatures and break record-high temperatures.
FOX Weather reports that most records could fall in Michigan, with others also impacted farther south.
More than 44% of the continental U.S. is impacted by moderate to exceptional drought, according to the U.S. Drought Monitor.
A seasonal outlook from the National Oceanic and Atmospheric Administration (NOAA) forecasts above-normal heat for most of the country this summer.
The Associated Press contributed to this report.