Some snow can cause slick surfaces Sunday evening Details >
Dec 19, 2013; 5:00 AM ET Snow showers for Edmonton on Friday, meanwhile a heat wave continues in Southwest Australia.
Similar to the days prior to Thanksgiving, the worst weather will focus on the days prior to Christmas as millions of travelers take to the roads and skies in the U.S. and southern Canada.
Despite a brief warmup in Chicago, wintry conditions will span the weekend.
Warm air is forecast to surge into much of the eastern half of the nation by the weekend and will be accompanied by heavy rain and flooding risk in some locations.