Experts Say When Northern Illinois Will Warm Up And Stay That Way

As I'm writing this, the current temperature throughout most of Northern Illinois is 10 degrees above zero, with a wind chill of 4 degrees below zero, heading for a daytime high of 24 degrees. If you've stepped outside this morning, you already know the question on most everyone’s mind: When is it finally going to warm up, and more importantly, stay that way?

The answer, as it turns out, depends on how much patience you’ve got.

History shows that “false spring” is very real around here. While we can get teasing warmups in March, they rarely last. In fact, Chicago’s average last freeze typically happens around April 21, and in parts of Northern Illinois, freezing temperatures can linger into early May. So even when we get a 70-degree day (like this coming Monday), winter may not be done with us just yet.

Looking back, the extremes are pretty wild. The earliest “last freeze” on record in the area came on March 19, 1925, which gave residents an early and steady spring. On the flip side, 1992 dragged winter out until May 25, a reminder that Midwest weather can be brutally unpredictable.

If You've Lived In This Area For A While, You Already Know That March And April Can Be Wildly Unpredictable When It Comes To Weather Conditions

Meteorologists say that unpredictability is exactly what makes this time of year so tricky to figure out. March and even early April often bring temperature swings, bouncing between warm and mild to downright middle-of-winter conditions. It’s not unusual to see sunshine and temps in the 60s one day, followed by snowflakes the next.

So when does it actually warm up for good in Northern Illinois?

Most experts point to late April into early May as the point when temperatures begin to stabilize across northern Illinois. That’s when the risk of freezing drops off significantly, and warmer days start to outnumber the cold ones.

Until then, just know that spring-like temperatures are just flirting with you. They're not ready for commitment just yet.