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Ontario highway conditions and winter driving
Ontario Road Conditions and Highway Weather
Radar and live pavement conditions on the 2 main highways of Ontario — plus the winter tire rule, the freezing level and where the province itself publishes closures.
Updated Sep 20, 2026 10:51 AM UTC · Mostly dry, wet in places
Lowest 6°C near Cornwall · Highest wind 13 km/h near Ottawa
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Ontario has no winter tire law — the province recommends them and makes every insurer offer a discount for them — and the winter it asks drivers to manage without one is the lake-effect kind: snow squalls off Lake Huron across Highway 401 between Chatham and Woodstock, squalls off Lake Ontario between Belleville and Kingston, freezing rain up the Ottawa Valley. This page follows the 401 from Windsor to the Quebec line and the Queensway through Ottawa, with the surface condition estimated along each from radar and analysis, the temperature and the precipitation type, beside what Ontario 511 itself reports.
- Highways covered: 2
- Winter tires: Not required by law; recommended, with an insurance discount
- Official service: Ontario 511
Weather data from Sep 20, 2026 10:51 AM UTC
6°C
16°C
13 km/h
101.3-101.8 kPa
Major highways in Ontario
The corridors this page follows, each with its own page. Surface and temperature are the latest readings along the whole road; the summits are where the same road is a different drive.
| Highway | Runs | Surface now | Lowest temp. | Highest wind |
|---|---|---|---|---|
| Highway 401 | Windsor – Quebec border | Mostly dry, wet in places | 7°C | 14 km/h |
| Highway 417 (Queensway) | Arnprior – Quebec border | Mostly dry, wet in places | 6°C | 6 km/h |
- Highway 401 — Windsor to the Quebec line through London, Toronto and Kingston: the busiest road on the continent, and between Chatham and Woodstock the one the lake-effect snow squalls close.
- Highway 417 (Queensway) — The Queensway through Ottawa and on to the Quebec line: the freeway of the snowiest big city in Canada, with the open stretch east of Orléans where the wind drifts it shut.
45 current reports along the route, including 1 full closure. The 8 most serious are listed below. Always check with Ontario 511 before setting off.
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Road closed
Closure on HWY 401 Westbound
Nightly Construction (Cancelled for Today) on HWY 401 Westbound Express between RENFORTH DR, Toronto and WINSTON CHURCHILL BLVD, Mississauga. ALL LANES CLOSED.
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Lanes blocked
Road work on HWY 401 Westbound
Nightly Construction on HWY 401 Westbound On-ramp at BROCK ROAD, Pickering. ALL LANES CLOSED.
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Lanes blocked
Road work on HWY 401 Eastbound
Continuous Construction on HWY 401 Eastbound On-ramp at Highway 4 / Colonel Talbot Rd, London. ALL LANES CLOSED.
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Lanes blocked
Incident on HWY 417 Eastbound
Disabled Vehicle on HWY 417 Eastbound at BELFAST RD, Ottawa. Left shoulder and 1 left lane closed.
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Lanes blocked
Incident on HWY 410 Southbound
Disabled Vehicle on HWY 410 Southbound at HWY 401, Mississauga. Right lane and right shoulder closed.
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Restriction
Road work on HWY 35/115 Northbound
Nightly Moving Maintenance Closure on HWY 35/115 Northbound between HWY 401, Clarington and HWY 35, . 1 Alternating Lane(s).
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Restriction
Road work on HWY 417 Westbound
Daily Construction on HWY 417 Westbound Off-ramp at RICHMOND RD (IC 130)/BAYSHORE DR, Ottawa. 1 Alternating Lane(s).
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Restriction
Road work on HWY 4 Southbound
Daily Construction on HWY 4 Southbound between Tempo Road and Clinton Line, St Thomas. 1 Right Lane(s).
Ontario Winter Tire Rules
Ontario has no winter tire law. The province recommends them — its winter driving page says they improve traction in frost, snow and ice and shorten braking distances by as much as 25% — and requires insurers to offer a discount to drivers who fit them, and that is the whole of the rule. Studded tires are the exception: legal on vehicles registered in Northern Ontario, not in the south.
What the law says
No Ontario law requires winter tires on a passenger vehicle. The province recommends them for frost, snow and ice, and since 1 January 2016 every auto insurer in Ontario has had to offer a discount to a driver who installs them — ask your insurer, because the amount is theirs to set. There is no chain law for cars either.
Studded tires
Studded tires are allowed on vehicles registered in Northern Ontario — the districts from Parry Sound and Nipissing north — and are not allowed in Southern Ontario unless the vehicle is registered in the north or visiting from outside the province. A car registered in Toronto, Ottawa or London may not run them.
How you will know it is active
- Ontario 511, which reports the road condition of every provincial highway section, closures and the position of the plows
- The OPP's travel advisories and highway closures, posted as they are made
- Environment and Climate Change Canada's snow squall warnings, which are the signal on Highway 401 west of Woodstock
There is no seasonal switch here. What changes is the road, and Ontario 511 ↗ is the province's own account of it before you set off.
Source: ontario.ca, Winter driving, checked September 9, 2026.
When roads get bad in Ontario
What the road normally throws at you, month by month, from Environment and Climate Change Canada's 1981–2010 normals at Toronto Pearson International Airport, Ottawa (Central Experimental Farm), London International Airport and Sudbury Airport — four stations, four climates, and each month names the worst of them and the place that measured it. This is what the month is usually like, not a forecast and not a rule.
- Jan Snow 60 cm of snow in an average month at Sudbury, with 31 nights below freezing there.
- Feb Snow 52 cm of snow in an average month at Sudbury, with 28 nights below freezing there.
- Mar Snow 35 cm of snow in an average month at Sudbury, with 29 nights below freezing there.
- Apr Freezing rain Freezing rain on about 0.8 day a month somewhere on the network, and 19 nights below freezing at Sudbury.
- May Rain and fog Frost is rare even at Sudbury, the coldest of the four; the hazards are rain, fog and the odd summer storm.
- Jun Rain and fog Frost is rare even at Sudbury, the coldest of the four; the hazards are rain, fog and the odd summer storm.
- Jul Rain and fog Frost is rare even at Sudbury, the coldest of the four; the hazards are rain, fog and the odd summer storm.
- Aug Rain and fog Frost is rare even at Sudbury, the coldest of the four; the hazards are rain, fog and the odd summer storm.
- Sep Rain and fog Frost is rare even at Sudbury, the coldest of the four; the hazards are rain, fog and the odd summer storm.
- Oct Cold nights 12 nights below freezing at Sudbury; the high passes can still see snow.
- Nov Freezing rain Freezing rain on about 3.0 days a month somewhere on the network, and 25 nights below freezing at Sudbury.
- Dec Snow 63 cm of snow in an average month at Sudbury, with 30 nights below freezing there.
Source: Environment and Climate Change Canada, Canadian Climate Normals 1981–2010, through the MSC GeoMet API. Snowfall is the monthly total; nights below freezing are days whose minimum was at or under 0 °C.
Ontario 511 is the traveller information service run by the Ministry of Transportation of Ontario, at 511on.ca, by web, app and phone. It is the province's own account of its highways, and it publishes:
- The road condition of every provincial highway section, as the maintenance contractors, the OPP and ministry staff report it
- Highway closures, collisions, construction and forecasted driving conditions
- Images from more than 900 cameras, and the position of the plows
- Traffic speeds, rest areas, food and fuel along the way
Ontario 511 and the conditions on this page
Ontario 511 reports what the contractors and the OPP have seen and declared for each section: bare and dry, partly snow covered, closed. What this page adds is the layer under those declarations — the surface condition estimated along the whole road from radar and analysis, and the temperature and precipitation type, which west of Woodstock is the difference between rain and a snow squall.
Ontario Winter Driving FAQ
- Are winter tires mandatory in Ontario?
- No. Ontario has no winter tire law; the province recommends them and requires every auto insurer to offer a discount to drivers who install them, which has been the rule since January 2016. Studded tires are the one thing the law does settle: allowed on vehicles registered in Northern Ontario, not on those registered in the south.
- Which part of Highway 401 closes most in winter?
- The stretch between Chatham and Woodstock, west of London, where snow squalls off Lake Huron cross the highway with no warning and take the visibility to nothing. On 10 December 2025 the OPP responded to 400 crashes in southwestern Ontario in one morning; on 27 January 2026 squalls off Lake Ontario closed the 401 between Belleville and Trenton for most of a day after collisions involving about 50 vehicles.
- Where does Ontario publish road conditions and closures?
- On Ontario 511, run by the Ministry of Transportation: the condition of every provincial highway section as the maintenance contractors, the OPP and the ministry report it, closures, roadwork, the position of the plows and images from more than 900 cameras. Municipal roads are each city's own.
- How much snow do Ontario's cities get?
- Less than the province's reputation in the south, more in the snowbelts. On Environment and Climate Change Canada's 1981–2010 normals Toronto Pearson averages 108 cm of snow a year on 44 days; Ottawa 176 cm on 52 days; London, in the Huron snowbelt, 194 cm on 60 days; and Sudbury 263 cm on 75. Freezing rain is the other hazard, five to eight days a winter in each of the three southern cities.
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