Peterborough gets the full Ontario winter: lake-effect snow off the Kawarthas, freezing rain, and long stretches of packed ice on side roads that get plowed later than the arterials.
Winter tires are the single largest safety upgrade available for that environment, and the reason is not tread pattern — it is chemistry.
It is the rubber compound, not the tread
An all-season tire compound stiffens as the temperature drops below roughly 7 °C. A stiff tire cannot conform to the road surface, and grip falls away even on clean, dry pavement.
A winter compound stays flexible well below zero, and the tread adds thousands of small sipes — biting edges that grab snow and channel away the thin water film that makes ice slippery. In real testing, stopping distances on snow and ice are dramatically shorter than an all-season, and the gap grows as the temperature falls.
Look for the mountain and snowflake
The three-peak mountain snowflake symbol on the sidewall means the tire has met a defined severe snow traction standard. The older M+S marking does not — it is a tread pattern designation and appears on plenty of tires with no cold-weather compound at all.
All-weather tires, a distinct category, do carry the snowflake and can legitimately run year-round. They are a reasonable compromise for a low-kilometre city driver, and a compromise you will notice on a bad day out on a county road.
Four, always
Fitting two winter tires is worse than fitting none, because it creates a deliberate grip imbalance. On front-wheel drive, winters on the front only gives you a car that steers and stops at the front while the rear breaks loose in corners — the hardest skid for most drivers to correct.
A second set of rims usually pays for itself
Mounting and dismounting tires from a single set of wheels twice a year costs more in labour than a set of steel rims does over a few seasons, and it is harder on the tire beads and on your TPMS sensors. Swapping wheels is faster, cheaper each visit and gentler on everything involved.
- Book the changeover in October — November is our busiest month by a wide margin
- Most Ontario insurers give around a 5% discount for winter tires; ask your broker what dates they require
- Replace winter tires below about 4 mm of tread, well before the 1.6 mm legal minimum
- Store them clean, dry, out of sunlight and stacked flat or hung, not standing on the tread