In anticipation of this weekend’s snow system the city of Ames has decided to activate its snow ordinance beginning at 8 a.m. Saturday.

The ordinance takes effect when two inches of snow falls on major arterial streets, and prohibits parking on makred snow routes. Vehicles parked on snow routes after the ordinance is activated will be ticketed and towed, according to a city news release.

The city also asks that people avoid parking on all streets, but only snow routes will result in tickets.