Early blast of heat & humidity leaves millions sweltering across US

A blast of heat and humidity in the Midwest and Northeast days before the official start of summer put a wet blanket on outdoor activities from festivals to sports camps as officials urged people to take precautions.

Cities that opened cooling centers this week advised that Wednesday's Juneteenth holiday means some public libraries, senior centers and pools where residents could beat the heat will be closed.

The dangerous temperatures were expected to peak in the eastern Great Lakes and New England on Wednesday and Thursday, and in the Ohio Valley and Mid-Atlantic on Friday and Saturday, the National Weather Service said. Heat index readings were expected to reach 100 to 105 degrees (37.7 C to 40.5 C) in many locations.

People and even zoo animals were forced to find ways to thwart the muggy weather.

An organization that provides produce to areas with limited access to fresh food in Columbus, Ohio, prepared frozen towels and packed cold water for their workers.

Hydration is the ke