A “white Christmas” is defined as having at least 1 inch of
snow on the ground on December 25. It should come as no surprise
that the highest odds are in northern Illinois. In general, the
odds are about 40-60 percent in the northern third of Illinois,
20-40 percent in central Illinois, and 0-20 percent in southern
There can be large differences between nearby sites, however.
Snowfall is notoriously difficult to measure with blowing,
drifting, and melting. Two nearby sites may have different
results due to exposure to the sun and the wind as well as the
dedication of the observer to report on Christmas Day.
Last year, just a little bit of snow was on the ground in parts
of the northern half of Illinois on December 25, 2014, which was
hardly impressive, Angel said.
One of the largest amounts of snow occurred in Chicago in 1951
with 17 inches on Christmas Day. Rockford had 14 inches of snow
in 1951 and in 2000.
“The odds of a white Christmas this year may be a little better
than you would think,” Angel said. “While December has been
incredibly mild so far, 10 degrees above average, but that could
change if a strong low-pressure moved through the Midwest around
[Lisa Sheppard, Illinois Water