Here's a timeline of how Chicago-area winter storm will unfold

Winter storm warnings will go into effect in the Chicago area overnight, and snow is expected to start falling while most area residents are asleep.

That snow could have significant impacts on the morning commute, and though it will transition to rain in the southern suburbs, nearly every part of the Chicago area could see significant accumulations before all is said and done.

With the exception of areas along Lake Michigan, 6-to-12 inches of snow are possible through Saturday afternoon, with the heaviest totals west and north of the city.

Here’s a timeline of how things are expected to unfold.

Friday Morning

Snow is expected to start overnight, with accumulations starting to pick up just before daybreak, according to forecast models.

Snowfall rates could be heavy, with 1-to-2 inches per hour in some locations. That snow could cause issues during the morning commute, with motorists encouraged to use caution if they have to hit area roadways.

Friday Midday

While snow is expected to continue in the north and west suburbs, areas near and south of Interstate 80 will likely see that snow transition into rain for a period of several hours.

Driving conditions still are expected to be difficult at times, according to National Weather Service officials.

Friday Afternoon

Rain is expected to slowly transition back to snow across the entire area, but the big story will be the wind, as gusts are expected to begin increasing during the afternoon hours ahead of the commute.

Friday Night

The strong wind gusts are expected to arrive Friday evening, with heavy snowfall once again causing significant travel issues as “blizzard-like” conditions could develop.

The National Weather Service says that conditions could make travel “very difficult to impossible” during this time, and officials are urging residents to avoid driving if at all possible.

Saturday

The storm will slowly move out of the area, with some lingering snow showers still possible. Winds will slowly begin to ease, but the big story will be the temperatures, as they will start to drop quickly behind the system as it exits.

Sunday

Some scattered snow showers are possible, but dangerous cold is expected to take hold in the area, with highs in the single digits and wind chills plunging below zero.

Monday

Possibly the coldest temperatures of the week will occur Monday and into the evening hours, with wind chills dropping to as much as 20-to-30 degrees below zeroes.

High temperatures during the day may struggle to get above zero, according to forecast models.