Brendan Gallagher, 8, makes a snow angel at a park on South Michigan Avenue earlier this month. (John J. Kim/Sun-Times)
There’s “White Christmas,” and then there’s a White Christmas that is followed by a warning from the National Weather Service.
On Friday, Christmas Eve, there is a chance of snow in the morning and snow likely -- up to one inch -- in the afternoon, according to the National Weather Service. Friday night, people heading out to late night pre-Christmas services may be traveling amid snowflakes, as well, as there is a 50 percent chance of snow then, the weather service says.
On Christmas Day, it will be cloudy with a chance of snow showers in the morning, then snow showers likely in the afternoon, with some accumulation possible, according to the weather service. High temperatures will be around 30 degrees.
Past Christmas Day, though, the weather service is urging everyone who has travel plans this weekend in the Chicago metropolitan area to closely monitor forecasts that are tracking potentially significant lake effect snow this weekend.
Cold north to northeast winds blowing over the relatively warm waters of Lake Michigan could result in accumulating lake effect snow over northeast Illinois and northwest Indiana this weekend, according to the weather service. The weather service’s advisory is for the area that includes Chicago, Waukegan, Wheaton, Joliet, Kankakee, and Gary, Valparaiso, Morocco, and Rensselaer, Indiana.
These lake effect snow showers could begin as early as Friday or Friday night, but are more likely to begin later Saturday, and last through Sunday night, according to the weather service.
While it is far too early to even guess how much snow could fall, the weather service was saying early Thursday, early indications however, are that portions of the Chicago area or northwest Indiana will likely receive accumulating lake effect snow. Given the potential for the lake effect snow to last for a prolonged period of time, the weather service says, “the potential does exist for locally significant snowfall totals.”
And while it’s also too early to pinpoint where the lake effect snow will occur, current indications from the weather service are that eastern Cook and eastern Will counties and Lake County in northwest Indiana stand the greatest chance of seeing accumulating lake effect snow. However, as the weather service points out, just a slight shift in the wind direction could result in a significant shift in the location of the greatest snowfall.
The weather service advises anyone with travel plans this holiday weekend in the immediate Chicago metropolitan area to closely monitor later forecasts regarding the potential for accumulating lake effect snow.