Parts of northern Illinois see historic Halloween snowfall

A year ago, most northern Illinoisans were looking at high temperatures above 50 degrees for trick-or-treating, with some light rain here and there.

A year later, many of those same areas are seeing record snowfall.

As of 11 a.m. Thursday, snowfall totals reached 2.9 inches in Princeton, about 2 inches in DeKalb, 2 inches in Mendota and Harvard, and 1.5 inches in Sterling, Batavia and La Salle. A total of nearly 1.5 inches of snow in Crystal Lake, 1.2 inches in Earlville, 1 inch in Ottawa, 0.9 inches in Sugar Grove, 0.8 inches in Barrington, 0.5 inches in Glen Ellyn and Elgin, 0.2 inches in Crest Hill and 0.1 inches in Plainfield also have fallen by that time.

Todd Kluber, meteorologist for National Weather Service Chicago, said this isn't the first time there has been snow accumulation on Halloween. He said the last time that happened in the Chicago and Rockford areas was in 2014.

“And that was one tenth of an inch,” Kluber said.

The six times there have been a trace of snowfall on Halloween in the Chicago area were in 1895, 1917, 1918, 1926, 1955 and 1993. Around Rockford, trace Halloween snowfalls occurred in 1917, 1918, 1926, 1935 and 2017.

However, the snowfall for Halloween this year is not the earliest measurable snowfall northern Illinois has seen, according to weather officials. That occurred in the area on Oct. 12, 2006.

According to the National Weather Service, 0.3 inches of snow fell at O'Hare International Airport in Chicago that day. The previous record there was 0.2 inches of snow on Oct. 18, 1972 and 0.7 inches of snow on Oct, 18, 1989.

According to a Nov. 1, 1989 story from Northwest Herald, some parts of the Chicago area "shoveled away 6 inches, while the rest looked for snow scrapers buried somewhere in their car trunks" on Oct. 18, 1989. An Oct. 21, 1989 Northwest Herald story said the storm had dumped more than 8 inches of snow in northern and central Indiana, and Marengo saw 2 inches of snow from that storm, according to National Weather Service.

Thursday's snowfall marks the snowiest Halloween on record for DeKalb since 1895, according to reports from the Northern Illinois University's National Weather Service Cooperative Station.

It's also the sixth snowiest October on record in DeKalb, with the most – 8 inches of snow recorded – for the month of October in 1929, station records show.

According to research by NIU's David Changnon, distinguished teaching professor and geographic and atmospheric sciences department chair, no other previous Halloween experienced measurable snowfall in the 24-hour period ending at 7 a.m. on Halloween day.

Although Rockford saw trace snowfall and didn't see any accumulated snow on that day in 2006, Kluber said, Rockford's recorded earliest snowfall was Oct. 12, 1909 with 0.2 inches of snowfall.

Typically, Kluber said, the first non-accumulating snowfall in northern Illinois comes in late October and early November. He said the first accumulating snowfall in the area usually happens in mid to late November and snowfall of an inch or more typically happens in early December.

The snowfall this Halloween is still an anomaly, though, Kluber said.

“We’re well ahead of average at least for first one-inch snowfall, two weeks ahead of schedule for first measurable snowfall and right on average for any snowfall,” Kluber said.

For as record-breaking as the snowfall for this Halloween is in northern Illinois, areas out of state have seen about eight times that amount in the past. According to the National Centers for Environmental Information, many areas in Iowa had up to 2 inches of ice accumulate on top of 8 to 15 inches of snow after everything was said and done in 1991.

Shaw Media and Daily Chronicle reporter Kelsey Rettke contributed to this story.