A vast heat wave, which has impacted the Midwest this week, is extending eastward, raising concerns about record-high temperatures for millions more individuals. Relief is not expected until after the Fourth of July weekend.
Currently, more than 160 million people are facing extreme heat warnings or heat advisories. This marks the second or third consecutive day of severe warnings for many, advising avoidance of outdoor activities during the hottest periods of the day.
The combination of triple-digit temperatures and high humidity levels is creating oppressive conditions, causing heat index readings to soar. Experts emphasize that the heat index provides a more accurate depiction of how hot it feels outside compared to the temperature alone.
On Tuesday, various locations experienced harsh heat index levels: 106 in Chicago, 113 north of Milwaukee, 103 in Cleveland, and 113 in Southern Illinois. The Weather Service predicts heat index values ranging from 100 to 115 degrees in cities from Kansas City to Boston on Wednesday.
Radley Horton, a professor at Columbia University’s Climate School, highlighted the unusually high humidity that characterizes this heat wave. High moisture levels in the air contribute to warmer nights, as temperatures remain relatively stable between day and night.