(WBBM Newsradio/CBS) — The city’s full fleet of 300 plows will be out all weekend as they tackle the main thoroughfares and streets.

Mayor Rahm Emanuel says this week’s snow event is a bit different because it’s coming in waves.

“This storm system is different. Usually you see a big dump and then it’s over. This is coming, stopping, coming, stopping, coming and everybody is going to be working all the way through to make sure people are safe,” Emanuel said at a Friday news conference.

Chicago Streets and Sanitation Commissioner John Tully estimates the city will have gotten a full foot of snow by Saturday night, over four days.

Chicago Public Schools made the call to close Friday. The mayor defended that decision.

“If safety is your primary concern, you evaluate all the other options. It’s a single day off. We’ll make it up at the end of the school year. I don’t regret the decision,” he said.

Although the schools were closed, the city’s 80 libraries, warming centers and community centers are open.

Emanuel says from the roads to public transportation to warming centers, the city is prepared for the long haul.

“From public transportation, to your roads, to your wellness check-ins to making sure fire hydrants are cleared, I think we are there and prepared,” he said.

Garbage service continues.

Six warming centers are opening, including 10 S. Kedzie, which is open 24/7.