CHICAGO (CBS) —Just days after the first big winter storm of the season blanketed the Chicago area with as much as 8 inches of snow, another storm system clobbered the Chicago area with the most snow that has been seen in years.

A Winter Storm Warning was in effect until 6 p.m. Sunday, but the snow kept falling even after that. Some parts of the Chicago area got more than a foot of accumulation.

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10 p.m. Between Saturday night and Sunday night, O’Hare International Airport canceled 231 flights because of the winter storm, while Midway International Airport canceled 71.

9:36 p.m. The Department of Streets and Sanitation spent many hours clearing arterial streets. The department said a new crew would take over at 10 p.m. Sunday and begin clearing residential streets.

Salt spreaders had been working since the snow began falling Saturday afternoon.

9:17 p.m. The snow was blamed for a roof collapse Sunday evening at an abandoned building at 8147 S. Racine Ave. in the Auburn Gresham neighborhood. The Department of Buildings said a bow-truss roof gave in due to a large load of snow.

5:30 p.m. While kids were building snowmen and sledding in Warren Park in the West Rogers Park neighborhood, shoveling the snow in Chicago neighborhoods was a Sisyphean task. CBS 2’s Dana Kozlov and her crew even had to be dug out at one point.

5:14 p.m. The snow left a thick coating on sheets of ice over Lake Michigan Sunday afternoon, as CBS 2’s Marissa Parra documented.

4:52 p.m. The weather is believed to be to blame for two separate multi-vehicle pileups on the Dan Ryan Expressway at 47th Street. Both incidents happened in the southbound express lanes.

The first incident happened in the southbound express lanes at 9:53 a.m., and four vehicles were involved. The second happened at 10:43 a.m. and seven vehicles were involved.

4:22 p.m. CBS 2 Meteorologist Mary Kay Kleist reports Peotone and Oak Park have now exceeded the one-foot mark for snow accumulation.

2:43 p.m. The area has seen impressive snow totals from this event, with some areas flirting with a foot. As of just before 2 p.m., Plainfield and Peotone were reporting 11.2 inches, Romeoville and Tinley Park 10 inches, Crown Point and Joliet 9.5 inches, and Chicago’s Lakeview neighborhood 9.4 inches, CBS 2 Meteorologist Mary Kay Kleist reported.

1 p.m. As of 1 p.m. Sunday, 146 flights had been canceled at O’Hare International Airport and 63 had been canceled at Midway International Airport.

8:40 a.m. Sunday A winter storm warning is still in effect for the Chicago area until 6 p.m. The system’s snow has lightened in intensity since Saturday but will continue to bring moderate to heavy snow at times.

The Illinois Department of Transportation offered some tips for those who do have to go out: Dial *999 in the Chicago area for assistance in case of emergency and remain inside your vehicle if you are involved in a crash.

However, it is suggested to stay off the roads unless completely necessary.

10:25 p.m. CBS 2 Meteorologist Tim McGill reports several more inches of snow are possible overnight, with 5 to 10 inches possible by the time it’s all said and done, making it easily the biggest snowfall of the season so far, and the biggest of the past few years.

Heaviest snowfalls will continue through about 1 a.m., with some blowing and drifting snow likely Sunday morning.

As it starts to get colder tomorrow morning, and the snow gets lighter and fluffier, visibility will be reduced even further.

A Lakeshore Flood Advisory also is in effect through 3 a.m. Monday, with strong winds whipping up waves of up to 11 feet on Lake Michigan.

10:15 p.m. Chicago’s full fleet of 300 salt spreaders and plows are still working to clear main streets through the night, and will move to side streets once the main streets are clear. You can track the city’s plows in real time by clicking here.

The snow has been falling steadily for the past few hours, and it’s quickly starting to pile up.

CBS 2’s Steven Graves has been monitoring the storm in the Mobile Weather Lab, driving all across the suburbs, where snow has gradually piled up and visibility has gotten worse.

Meantime, in the city, Streets and Sanitation snow plows have been focusing on the main streets and Lake Shore Drive, leaving residential side streets neglected early in the storm. Sidewalks are also getting little attention so far, with the heaviest snow expected to continue until about 2 a.m., and likely hours to go after that before the snow tapers off altogether.

“It’s all kind of bad out everywhere,” Angela Crenshaw told CBS 2’s Jeremy Ross.

9:05 p.m. So far the National Weather Service has received reports of 4 inches in Clifton, 3.6 inches in Kankakee, 3.2 inches in Peotone, 3.1 inches of snow in Romeoville, 3 inches in Rockford, 2.8 inches in Joliet, 2.5 inches in Oak Forest, 2 inches in Oak Lawn, and 2 inches in Saint Charles.

The National Weather Service said many roads have become snow-covered, creating hazardous travel conditions, with multiple crashes reported across the area. Moderate to heavy snow is expected to continue through early tomorrow morning. People are advised to avoid non-essential travel.

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8:15 p.m. A total of 93 flights have been canceled at O’Hare International Airport, and another 16 have been canceled at Midway International Airport. No significant flight delays have been reported so far.

8:10 p.m. So far the National Weather Service has received reports of 2.1 inches of snow in DeKalb County, 1.5 inches in Kankakee County, 1.3 inches in Iroquois County, 1.1 inches in Peotone, 1.1 inches in Romeoville, 1 inch in Joliet, 0.8 inches at Midway Airport, and 0.6 inches at O’Hare Airport.

But the National Weather Service said the heaviest part of winter storm was just getting started around 7 p.m., with rates climbing to at least 1 inch per hour. The heaviest snowfall is still expected for most of the Chicago from early this evening until about 2 a.m. tomorrow.

8:05 p.m. CBS 2’s Steven Graves in the Mobile Weather Lab noticed winds picking up and side streets slowly getting worse in the northern suburbs.

6:45 p.m. CBS 2 Meteorologist Mary Kay Kleist reports conditions are going downhill fast, with snow rates increasing soon to 1-2 inches per hour.

6:05 p.m. A total of 78 flights have been canceled at O’Hare International Airport, and another 16 have been canceled at Midway International Airport. No significant flight delays have been reported so far.

5:45 p.m. CBS 2’s Steven Graves is monitoring the storm from the Mobile Weather Lab, and said while there were a good number of cars on the roads early Saturday evening, conditions were expected to get worse over the next few hours.

Of course, the best advice is for people to stay at home as heavier snow moves in and visibility gets worse as the night goes on.

4:45 p.m. CBS 2’s Steven Graves is headed to the western suburbs in the Mobile Weather Lab, and said visibility is getting worse the further west they go. Snow was already sticking to some main roads in Naperville, and crews were expected to be treating streets for at least two hours ahead of the heaviest snowfall later this evening.

3:50 p.m. Meteorologist Ed Curran says a mix of snow and graupel started falling in the northwest suburbs around 3 p.m., quickly covering an untreated road.

3:25 p.m. The city’s Department of Streets and Sanitation says its full fleet of more than 300 snow plows and salt spreaders is prepared to keep the city’s main streets and Lake Shore Drive as clear as possible for traffic this weekend, particularly emergency vehicles and CTA buses. Commissioner John Tully also said the city has more than 360,000 tons of road salt stored throughout the city.

You can track the progress of plows in your neighborhood with the city’s online Plow Tracker.

Office of Emergency Management and Communications executive director Richard Guidice said the city also will be working closely with ComEd and other electric utilities in case of any power outages during the storm.

“We urge residents to take precautions, plan accordingly, and allow extra time while driving. Travel could be very difficult due to very low visibilities and snow-packed roads,” Guidice said. “Also, while driving, keep plenty of distance between you and vehicles in front of you.”

Guidice encouraged people in Chicago to stay in contact with neighbors and family, and help them as needed, particularly the elderly and disabled. With a lot of heavy, wet snow expected to fall, Guidice said people shoveling sidewalks should work slowly and wear plenty of layers to keep warm.

Anyone who needs to find a warming center during the storm, or who wants to request a well-being check for a neighbor, friend, or relative can call 311.

Guidice also said, with high waves expected on Lake Michigan this weekend, anyone parked along the lakefront should consider moving their vehicle away from the lake if possible.

 3:19 p.m. A total of 52 flights already have been canceled at O’Hare International Airport, and another 17 have been canceled at Midway International Airport. No significant flight delays have been reported so far.

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