The Chicago area is set to see some measurable snow this weekend, but just how much and when?
A Winter Storm Warning has been issued for McHenry, Lake, DeKalb, Kane, DuPage, and Cook counties in Illinois, as well as Kenosha County in Wisconsin.
The warning begins Saturday morning in Kenosha and DeKalb counties, and begins at 1 p.m. in the rest of the Chicago-area.
Wind gusts as high as 30 mph are possible and snowfall rates could approach 1 to 2 inches per hour, according to the National Weather Service. While heavily-traveled roads aren't expected to become snow-covered, elevated surfaces and grassy surfaces will be, and motorists should use caution during the storm.
Here’s a breakdown of what you can expect:
When will the snow begin?
Rain will start to develop during the morning hours Saturday and will continue falling through the afternoon.
10 a.m.-2 p.m.
The rain is expected to start transitioning to snow, particularly in north and northwest suburbs. Morning temperatures are expected to sit between 42 and 47 degrees, but will fall quickly into the 30s in the afternoon, with evaporation helping cool the atmosphere and set the stage for snow.
Snow is expected in areas north of the I-88 corridor, though rain is still expected for areas south.
6 p.m.-12 a.m.
Snow begins moving south. Things will begin tapering by the 8 p.m. hour for far northern locations and continue tapering as the system heads south for the evening. Most of the snow should track out of the area around 11 p.m. or midnight, according to forecasts.
Timing of the snow will depend largely on how quickly temperatures fall and if the storm stays on its projected path. Even the slightest change in the storm's path could have a dramatic impact on snow totals and timing.
When will it end?
The wet weather should be out of the area by Sunday morning.
Radars show that by 6 a.m., the Chicago area should be completely dry.
Where will snow fall?
Current models show a sharp line along Interstate 88. Areas around the line will likely see a mix of rain and snow while areas further north are expected to see all snow as the system continues.
Areas south of I-88 are expected to see mostly rain.
"It is a very narrow swath of snow," said NBC 5 Storm Team Meteorologist Pete Sack. "Fifty miles can be the difference between nothing and 6 inches of snow."
How much snow is expected?
The wet weather will likely dump anywhere from half an inch to 8 inches of snow, depending on your location.
Models still vary on just how much snow will fall. Some predict close to 8 inches possible in far northern locations, while others forecast lower than 3 inches.
Where snow does fall, expect "very big, heavy, wet snowflakes," Sack said.
Check back for the latest snow total projections and track this developing system here.