When signs are erected in each block giving notice thereof, no person shall park a vehicle within the block when snow or ice conditions exist and the conditions have not been remedied by the Public Works Department. The Superintendent of Public Works is hereby empowered to designate which blocks within the city shall be so posted. The sign posting the area shall read as follows:
"Parking Prohibited When Snow or Ice Conditions Exist (Until Treated) or Parking Prohibited When Snow or Ice Conditions Exist."
Penalty, see § 40.999