Toronto to Sudbury — Weather & Driving Conditions

Driving from Toronto, ON to Sudbury, ON? This 245-mile route follows Highway 400, Highway 69. TripCaptain checks the weather at every stop along the way — not just at each end — so you can see where conditions change before you pick a departure time.

What to watch for on this route

In the planner, TripCaptain highlights forecast weather risks between Toronto, ON and Sudbury, ON and summarizes the analysis with a Hazard Score™ from 0 to 100. A higher score indicates lower forecast risk, without guaranteeing road conditions.

• Lake-effect snow squalls: Squalls off Georgian Bay drop heavy snow in narrow bands north of Barrie — the road can go from clear to buried within a few kilometres.
• Whiteouts near Parry Sound: Blowing snow around Parry Sound can cut visibility below 400 m (¼ mile) in seconds, hiding stopped traffic ahead.
• Black ice: Overnight cold refreezes wet or slushy pavement, especially on bridges and shaded rock cuts — hardest to see at dawn.
• Two-lane closures: Heavy squalls or a single collision can close the two-lane stretches of Highway 69, with long detours — know whether the road is open before you leave.

When to go, season by season

• Spring (Mar–May): Snow lingers into April up north. Watch for morning black ice from overnight refreezing — leave once the sun has warmed the pavement.
• Summer (Jun–Aug): Easiest driving of the year. Watch for afternoon thunderstorms and heavier cottage-country traffic on Fridays and Sundays. Mornings are clearest.
• Fall (Sep–Nov): Conditions turn quickly — the first lake-effect squalls can hit by November. Morning fog is common near the water. Fit winter tires before the first snow.
• Winter (Dec–Feb): Peak hazard season. Squalls off Georgian Bay bring whiteouts and closures with little warning. Carry winter tires, leave in daylight, and wait out active squall warnings rather than driving through.

Compare departure times

Open Toronto to Sudbury in the planner to check the forecast for your date and compare nearby hours within your plan's limits. Save the trip to follow changing conditions in Live Mode.

Fuel, EV range, and rest stops

See a weather-adjusted fuel or EV energy estimate for the drive, sensible break points across the 245 miles, and a packing list matched to the conditions ahead.

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