Second wave of snowstorm hits Chicago Tuesday evening, with snow predicted to be worst in the northwest suburbs

A second wave of a heavy winter storm system moved in late Tuesday afternoon with snow resuming throughout the Chicago area, creating slick roads and complicating evening commutes.

The evening snow was predicted to “be worse the farther west and north you go,” said National Weather Service meteorologist David King.

Meteorologist Mark Ratzer said the Chicago area would see more light snow throughout the evening and into the early hours of Wednesday, which would see more intense winds and lower temperatures.

Ratzer said travelers may encounter issues with slippery roads and lower visibility farther from the city, “especially as the temperature slowly falls and the wind picks up.”

The weather service predicted the commute in and out of Rockford Tuesday evening to be one of the worst and warned in a social media update Tuesday that motorists throughout northern Illinois should be prepared for snowy roads and low visibility overnight. Depending on temperatures, wind gusts of 35 to 40 mph were expected Tuesday night in Chicago.

Winter storm warnings were issued farther northwest and north for several counties, including DeKalb, Kane, Boone, McHenry and Lake. As of 4 p.m., DuPage and Cook counties were reduced to a winter weather advisory until 4 a.m. Wednesday, according to the weather service.

A weaker system will continue through Wednesday night, and meteorologists have “growing confidence” that a stronger system will return Friday.

The National Weather Service received a number of reports of more than 2 inches of snow on the ground in the west suburbs, about 3.8 inches at Midway and about 3.2 inches at O’Hare as of Tuesday evening. A second push of snow late Tuesday is expected to be especially heavy northwest of I-55, meteorologists predicted.

Chicago was taken out of the winter weather advisory Tuesday morning, with meteorologists confident that the slushy storm mix will remain rain through the day. Temperatures at O’Hare International Airport and Midway Airport were already above freezing by 9 a.m., creating a slushy mix of snow and rain on the ground, particularly closer to the lakefront.

As of 4 p.m., 120 flights had been canceled at O’Hare and 40 were canceled at Midway, according to flight tracking website FlightAware. A ground stop to halt all flights due to ice and snow was temporarily ordered at O’Hare late Tuesday afternoon.

For much of Tuesday, most of the O’Hare cancellations were by United Airlines, which is one of two major U.S. carriers that operate Boeing 737 Max 9 jets that were grounded after a door plug blew out midflight on an Alaska Airlines jet Friday. United said Monday it had canceled a total of 200 Max 9 flights that day and expected “significant cancellations” Tuesday.

United also said it had saved about 30 flights by switching them onto other types of planes. The carrier found loose bolts and installation issues with the door plug during preliminary inspections, United has said, and the airline was working to return its 79 Max 9s to service “in the days ahead.”

At 6 a.m. Tuesday, official snow observations at the NWS Chicago headquarters in Romeoville came in at 1.9 inches at O’Hare and Rockford had 1.1 inches.

Another potential winter storm is expected to approach the Chicago area Friday, but predictions were largely uncertain as of Tuesday, King said. Next week, meteorologists are predicting frigid temperatures with wind chills as low as minus 20 degrees.

“We will get through this event and then fine tune that forecast,” King said. “It’s January and it’s just going to be the next winter storm.”

Meanwhile, the Chicago Department of Streets and Sanitation deployed 287 salt spreaders Tuesday morning. The snow fleet focused on Chicago’s main arterial streets, DuSable Lake Shore Drive, and bridges and overpasses.

The Illinois State Police reported it had assisted in 42 incidents, including slide-offs, from midnight to 5:30 p.m. around the Chicago area. A state police representative said officers responded to 11 crashes involving injured people in the same time frame.

The city urged drivers to have a full tank of gas before heading out, yield to emergency vehicles and snowplows when driving and to carry an emergency kit with a cellphone charger, food and water. Drivers should also allow for extra time and leave ample space between cars, according to a news release.

Overnight parking bans are also enforced on more than 100 main streets in the city from 3 to 7 a.m. until April to allow enough space for snow removal.

Due to a strong El Nino, scientists predict that Chicago’s winter will be milder and drier than normal, with Monday’s overnight system the first “significant” storm of the winter.

Chicago Tribune’s Sarah Freishtat and Caroline Kubzansky contributed.

aguffey@chicagotribune.com