Jimmy Fallon
"The Tonight Show" host Jimmy Fallon (C) emerges from the water of Lake Michigan as he takes part in the Annual Polar Plunge in Chicago, March 2, 2014. Reuters/Jim Young

Comedian and late-night talk show host Jimmy Fallon took a quick dip in Lake Michigan, dressed in a full suit and tie, before rushing back out of the freezing water, and kept his promise to make the Sunday morning “Polar Plunge” with Chicago Mayor Rahm Emanuel.

According to reports, Emanuel had laid down a condition that if Fallon took the “Polar Plunge” to help raise money for the Special Olympics, the mayor would appear on Fallon's show in New York.

Emanuel wrote in his Twitter account: “Thx for the invite @jimmyfallon. You should toughen up for the big leagues. Do the Chicago Polar Plunge with me and I’ll join @FallonTonight.”

Fallon posted his picture on Instagram after the plunge, captioning it: “Officially PLUNGED!!!!! Thank you Chicago!!! Thank you Mayor. #polarplunge #coldneverbotheredmeanyway #frozen.”

Emanuel reportedly had said last summer that if the city's children read two million books as part of a Chicago Public Library program called "Rahm's Readers," he'd jump in the lake. Emanuel wore a green Chicago Public Library T-shirt and shorts as he took the plunge, with Fallon following.

Special Olympics Chicago President Jen Kramer reportedly credited Fallon and Emanuel with attracting more than 3,000 people to the event at the city's North Avenue beach. The number was more than last year's, when about 2,300 people took the plunge.

Fallon reportedly told Wednesday that he agreed to the challenge before realizing what it actually involved. He wrote on his Twitter account Saturday: “Anyone ever done a #PolarPlunge? Advice? @SpecialOChi it's gonna be coooooold.”

Many followers of Fallon motivated him to take up the challenge by creating the #JimmyPlungeWithUs campaign on Twitter.