In reply to CurlyStevo:
Not in itself they don't! Overall weather patterns give higher or lower chances of colder weather. Being stuck in a relatively mild pattern since late November means that a pattern change will probably occur before the end of winter - this pattern change could make it colder, or could send it mega mild. It would be highly unusual, and almost without historical precedent, for the current pattern to last until the end of March!
Anyway, even 1998, the worst winter ever, had conditions in the lakes for a while in April after a super mild Dec-Feb period, there will be cold snaps in any winter enough to bring stuff in. Sometimes conditions last a day, other times they last a month or more.