Matt Wilson takes the plunge.Photo by Lynn Trautman/LT Photo Evanston

Cool heads prevailed in the 2017 Ice Bucket Challenge, but these volunteers were cold all over.

With air temperatures a spring-like 60 degrees – and the water still in the wintry 30s – nearly 300 supporters of the Special Olympics gathered at Clark Street Beach on Feb. 20 to take the annual Polar Plunge. Each of the 300 raised a minimum of $100 to be eligible for a single, bone-chilling dip in Lake Michigan. All proceeds from the event benefit Special Olympics Illinois.

The event has grown since 1999 from one location to 21 across the state. In 2015, 7,666 plungers raised $2.25 million.

Perhaps knowing misery loves company, organizers encouraged participants to form teams to earn prizes and “spread the fun.” Bathing suits and even costumes ruled the day, but wetsuits were strictly forbidden.

A group with a higher tolerance for lower temperatures beat the plungers to the beach, jump-starting the Polar Plunge season with a SUPER Plunge at Clark Street beginning at 2 p.m. on Feb. 19. Each of these 60 Super Plungers collected $2,500 before diving into the freezing lake once an hour for 24 hours ending at 1 p.m. on Feb. 20.

One passer-by, noting the unseasonably warm day, wondered whether they had considered cancelling the frigid event “due to inclement weather.”