Around 200 people will brave today’s cold temperatures to jump into a lake. It’s all for a good cause — Special Olympics Iowa.He says they’ve raised a lot of money by getting pledges to jump into Big Creek Lake near Saylorville. Special Olympics spokesman Chuck Reed says this has become a fun fundraiser for the organization.This will be the fourth year for the Big Creek plunge, and another the group has in April at Iowa State has gone on for five years. Reed says they’ll still take people who are looking for a cool dip and a chance to raise money for a good cause.Registration begins at 11 A.M. with the plunge at 12:15. Reed says it was very warm for last year’s plunge, but the forecast doesn’t look so good this time.