Philadelphia will be in a state of snow emergency as of 9 p.m. Friday as Snowstorm Jonas bears down on the region.

Vehicles parked in snow emergency evacuation routes will be ticketed and towed to make way for the more than 400 snow plows that will be trudging down major thoroughfares and highways later today and Saturday, city officials said.

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Officials warned that vehicles parked too close to the curb impede the turning radius of salting and plowing equipment. 

The latest projections show between 12 and 20 inches of snow by the time the storm is expected to end Sunday morning.

Mayor Jim Kenney and his staff offered an update on the snow during a press conference Friday afternoon from City Hall.

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Vince Fenerty, executive director of the Philadelphia Parking Authority, said that the parking authority has offered 24-hour parking for $5 beginning at 5 p.m. Friday.

City Managing Director Mike DeBerardinis urged city residents to stay home and off the roads this weekend, as measurable snow amounts could be unpredictable. Normal trash pickup on Saturdays will be delayed a week, so plan accordingly.

Libraries and recreation centers will be closed this weekend.

Deputy Managing Director Clarena Tolson also reminded residents who’s pipes tend to freeze to keep water trickling through their lines in order to avoid that.