Rahm's Polar Challenge

Rahm's Polar Challenge (February 24, 2014)

When Jimmy Fallon called himself “Swimmy Fallon” on Twitter Monday, it became official: He had warmed to Mayor Rahm Emanuel's challenge and will join the mayor in taking a charity dip in Lake Michigan Sunday.

By entering cold water on a cold day, the New York-based host of “The Tonight Show” will stand up to Emanuel, earn his new show free publicity in the nation's third largest city and help a good cause.

The annual Polar Plunge, happening between 10 a.m. and Noon at North Avenue Beach, raises money for Special Olympics Chicago. Mayor Emanuel agreed to the brief winter swim after Chicago children read more than 2 million books in the city's Summer Learning Challenge.

Fallon agreed after Emanuel, via Twitter, told the talk-show host that he would come on the “Tonight Show” if Fallon would “toughen up” and take the plunge.

Fallon first tweeted that he worried it was a set up. But on Monday, the host said on Twitter, “Okay @RahmEmanuel I'm in. Lake Michigan will have a New York fish this weekend. #SwimmyFallon”

In a follow-up, Fallon noted that he'll do the swim in a suit and tie. He might consider having a wet suit underneath. Sunday's forecast calls for a high of 23 degrees, and the lake's temperature near the Chicago shore on Monday was 33 degrees, much colder than even the chilliest TV studio.

Chicago - I'm wearing a suit and tie for the #PolarPlunge. Show solidarity by wearing a necktie. (I'm not telling you what else to wear.)