Timing: When will the worst of Friday's snowstorm hit the Chicago area?

Editor's Note: Our latest weather story can be found here. Our original story, from Thursday, Jan. 11, continues below. Note that snow projections and timing may have changed.

Another round of significant snow is headed for the Chicago area, bringing the potential for several inches of accumulation and possibly even blizzard-like conditions at times, but when will it hit and when can you expect the worst of it?

Much of the area will be under a winter storm watch at some point during the system, but when it starts — and how much snow you will see — depends largely on where you live.

Here's a look at the timing for the upcoming system:

Friday Morning

Though some locations will see weather alerts beginning Thursday evening, most areas will see snow moving in from the southwest during the overnight hours early Friday morning.

According to the NWS, a "burst" of heavy snow Friday morning near and north of I-80 is expected to occur, with snow falling at a rate of 1-3 inches per hour.

According to the National Weather Service, the winter storm watch will go into effect in DeKalb, LaSalle, Kendall and Grundy counties on Thursday night. McHenry, Lake, Kane, DuPage, Cook, Will, and Kankakee counties in Illinois, as well as Lake and Porter counties in Indiana, will go under the watch at 6 a.m. Friday.

"A quick couple of inches are possible through 7 a.m. from a few bursts of heavy snow," NBC 5 Storm Team Meteorologist Kevin Jeanes said.

After 7 a.m., locations south of Interstate 88 will see the snow transition to rain as precipitation across the area will likely lighten before conditions worsen later in the day.

Friday Afternoon

The precipitation is expected to pick back up around or after 2 p.m. as wind gusts of 30 mph, possibly even higher, kick in.

Whether this precipitation is snow or rain or a mix of both will depend largely on temperatures, but the transition from rain to snow is expected to take place sometime between 2 and 5 p.m. across the area.

Friday Evening

Heavy snow is possible for the evening commute. The largest snowfall totals are expected to fall after 5 p.m. and into the overnight hours as temperatures continue to drop.

“Blizzard-like conditions” are possible during this window. 

But what does that mean?

The definition of a blizzard is at least 35 mph wind gusts with falling or blowing snow reducing visibility to a quarter mile or less for a period of three hours.

Overnight and Into Saturday Morning

Temperatures drop into the 20s between 10 p.m. Friday and midnight Saturday, which could lead to icy conditions. Light snow could also continue Saturday morning as feels-like temperatures drop into the single digits.

Sunday

Wind chills will drop to -20 and -30 degrees Sunday through Wednesday, with 20-30 mph wind gusts expected. These temperatures will mark the coldest days seen in the city since the end of January 2019.

Early Snow Total Projections

As of Thursday morning, models showed the highest snow totals will likely be in the northern part of the Chicago area, with widespread estimates ranging between 6 and 9 inches, though some locations could see up to 10 inches.

Totals get lower in the southern parts of the region, but much of the totals will depend on how far north the warm air and rain mix during the day.

Overall, area-wide totals between 5 and 7 inches are expected north of Interstate 80 and between 2 and 5 inches south of I-80.

The NBC 5 Storm Team is tracking this forecast as it develops. Stay tuned for updates as each system approaches.

Latest information on the Chicago snowstorm

You can find our latest stories on the Chicago snowstorm below:

• Live snow radar map: Track weather near you as storm snarls Chicago area
• Snow totals: Latest snow totals in Chicago and Illinois as snowfall as continues
• Illinois winter road conditions: Buses rerouted, crashes reported and more
• Power outages: Tens of thousands of ComEd customers without power amid winter storm
• Flights canceled: Ground delay at O'Hare, thousands of flights canceled across Chicago airports 
• School closures: More than 100 schools closed across Illinois