Are you dreaming of a white Christmas this year? Keep on dreaming, Chicago.
Meteorologists expect the day to be the opposite of a winter wonderland: dreary, cloudy and damp. The probability of getting more than 1 inch of snowfall has been historically low for the date, at around 35% — and those odds might be stacked higher against a magical day this year.
The city has only experienced one white Christmas in the past six years. It was 2022, and even then it barely qualified with 1 inch of snow. Before then, in 2016 and 2017, Chicagoans woke up to at least 2 inches of snow the mornings of Dec. 25.
“Typically, the Chicago area has a white Christmas about once every three to four years,” said Brett Borchardt, senior meteorologist at the National Weather Service office in Chicago. “It does not look like we’re gonna have a white Christmas this year, though. I know there are still some spots that have snow out there, especially in the north suburbs — that’s all going to go away.”
Borchardt said to expect highs near 40 degrees on Wednesday with showers, drizzles and even some fog.
Chances of a white Christmas in the United States have been historically best in Alaska, the Northern Plains and Rockies, the Great Lakes region and parts of the Northeast, according to 1991-2020 data from the National Oceanic and Atmospheric Administration.
In Illinois, the probability of more than 1 inch of snow on Christmas Day ranged from 20% to 50% over those three decades, with the likelihood increasing farther north. This year, AccuWeather more optimistically predicted a “medium probability” for a winter wonderland holiday across the northern part of the state.
Locations with the highest historical probability in the Midwest include Marquette, Michigan, with 96%; Duluth, Minnesota, with 92%; Wausau, Wisconsin, with 85%; Minot, North Dakota, with 82%; and Minneapolis–St. Paul with 74%.
Still, actual conditions may vary from year to year because of local weather patterns. For instance, the most snowfall on Dec. 25 in Chicago happened in 1950 when 5.1 inches blanketed the ground at Midway Airport after forecasters had predicted light snow for that day.
Even if it does snow, milder temperatures and warm soil might not allow for any significant snow accumulation.
And climate change is only complicating the timing, location and amount of snowfall across the United States.
It is largely day-to-day weather systems that dictate snow cover on a given day, rather than long-term warming, even as monthly average temperatures are increasing during the winter months, according to NOAA.
“Winters are warming at a faster rate than all the other seasons, but in Chicago, we haven’t seen a significant downward trend in snowfall, for lots of reasons,” said Trent Ford, the Illinois state climatologist. “Just because it’s warmer doesn’t mean you get less snowfall. Just because it’s colder doesn’t mean you get more snowfall.”
In fact, warming temperatures may enhance snowfall, he said, because warm air has a higher water-holding capacity, which allows clouds to hold more moisture. This in turn increases precipitation and — if temperatures on a given day are cold enough — snowfall.
Chicago winters are getting shorter with less snowfall in October and November, but warmer air during January and February is likely helping produce more snow during those months.
“Individual snow events in the cold core of the season may get snowier for a while even as temperatures warm,” wrote Michael Palecki, a physical scientist and project lead for climate normals at the National Centers for Environmental Information. “However, snow chances early and late in the season will likely decrease and the length of the snow season will shorten.”
In Chicago, snow seasons in the 1991-2020 period normally received 1 to 2 more inches of snow than in 1981-2010, according to Palecki, but the slight increase in snow totals did not lead to an increased chance of a white Christmas in the city.
“When you add into that the complexity of just looking at snowfall on one specific day, like Christmas, it’s even more wacky and variable and complicated,” Ford said. “Because we could have had the snowiest winter on record, and it just so happened that it didn’t snow on Christmas.”
While NOAA cautions against broad comparisons between climate normals, subtle differences between 1981-2010 and 1991-2020 show that more areas in the country experienced decreased chances of a white Christmas than experienced increases over the last decade.
Overall, 64% of over 2,000 locations across the country now get less snow than they did in the early 1970s, and another 36% have seen snowfall increase, according to an assessment of snowfall trends by science education nonprofit Climate Central.
Such locations might include those near large bodies of water like the Great Lakes, which can lead to intense local snowfall. So-called lake-effect snow happens when cold air from the north moves across relatively warmer open water. As the planet has warmed, so have the Great Lakes — Lake Michigan just had its warmest November in 30 years. These higher water temperatures and a reduced ice cover enhance evaporation from the lake, increasing its snow effect.
Even though Chicago is by the lake and it gets snow, it doesn’t get as much lake-effect snow as places downwind from a Great Lake like Buffalo in New York, Erie in Pennsylvania, and Kalamazoo, Sault Ste. Marie and Marquette in Michigan, which are all seeing upward trends in snowfall.
If anything, a December without snow can make hectic air travel in one of the nation’s busiest hubs a less stressful experience with fewer weather-related delays and cancellations. In 2022, a snowstorm in the days leading up to the city’s last white Christmas resulted in hundreds of flights being canceled from O’Hare and Midway airports.
And Chicagoans can still hold onto hopes of more white Christmas days to come.
“Even if we did have a significant downward trend in snowfall in Chicago — which, by the way, is expected over the next 50 or 60 years, because we’re going to continue to warm in the wintertime and we’re going to see likely less snowfall overall, especially pre-January snowfall,” Ford said. “Even if we did see that trend, it doesn’t mean necessarily that we won’t get snow on Christmas.”