Canada · In centimetres
Snow Day Predictor Canada
Will school be closed tomorrow?
Enter any Canadian city. Built for how school closures actually work here — in centimetres, and with the bus-versus-school split that decides most Canadian winter mornings.
Your Closure Chance
In Canada a bus cancellation is the likelier outcome — check the bus cancellation predictor for that.
Across Canada the Buses Go and the Schools Stay Open
This is the single most important thing to understand about a Canadian school morning, and it catches families out every winter. You check whether school is closed, see that it is open, put your child at the end of the driveway — and no bus ever comes.
Canadian boards rarely close schools outright. What happens instead is that the student transportation consortium cancels buses while the building stays open for anyone who can get there. Two organisations, two sets of criteria, two separate announcements.
So on a typical bad morning the honest answer is: no bus, but school is running. If that is your real question, the bus cancellation predictor is the tool you want. Consortia also split their territory into zones and cancel them independently, so a decision covering rural routes may leave town routes running normally.
It Is a Different Decision in Every Province
Canada is not one winter. The thing that closes a school in Halifax is not the thing that closes one in Saskatoon, and the thresholds are not comparable.
| Region | What actually closes schools | Rough trigger |
|---|---|---|
| Atlantic Canada | Rapid changeovers between snow, freezing rain and rain, plus Atlantic gales and power outages. Closes more readily than anywhere else in the country. | 15–20 cm, or any real icing |
| Quebec | Large system storms. High tolerance and heavy plow coverage, so closures need a genuinely major event. | 25 cm+ |
| Ontario — snowbelt | Georgian Bay and Lake Huron squalls. Intensely local, so cancellations are almost always by zone. | Buses at 10–15 cm; closures rare |
| Ontario — GTA and east | System storms and freezing rain. Dense plow coverage. | 20–25 cm |
| Prairies | Cold, far more than snow. Blizzards with blowing snow close highways and rural routes. | Wind chill −35 °C to −40 °C |
| Northern Canada | Extreme cold and whiteouts. Snow depth alone changes very little. | Wind chill, and visibility |
| Coastal BC | Very little snow, so almost nothing is equipped for it. A few centimetres genuinely disrupts Vancouver and Victoria. | 5–10 cm |
| Interior BC and Alberta | Mountain snow and road grade. Chinooks can reverse conditions within hours. | 20 cm+, or icing on grades |
Set the regional control in the form to match where you actually are — it moves the result substantially, and it is the main reason two Canadian cities get different answers to the same amount of snow.
Cold Closes More Canadian Schools Than You Would Think
Across the Prairies and the North, and in much of northern Ontario and Quebec, the more common trigger is not snow at all. Most consortia pull buses at roughly −35 °C to −40 °C wind chill, on mornings that are often clear and dry.
The reason is exposure, not driving. A child waiting at an unsheltered rural stop for a bus that is running ten minutes late is at risk of frostbite well inside that window, and a bus breaking down on an isolated road in that temperature is a serious situation. That is why northern policies are written as hard cutoffs rather than judgement calls.
The cold day calculator scores wind chill on its own and ignores snow, which is the right tool for a clear −38 °C morning.
Places We Cover in Detail
Ontario has the deepest coverage, because that is where snow day and bus cancellation searches concentrate.
Any other Canadian city works in the calculator above — these are the ones with their own page.
Canadian Snow Day Questions
How many centimetres of snow closes school in Canada?
Roughly 15 to 25 cm overnight puts a closure in play across most of the country, but the far more common outcome at those amounts is that buses are cancelled while the schools stay open. Atlantic Canada closes more readily because of freezing rain, and the Prairies and the North close for cold more often than for snow.
Why are Canadian buses cancelled but schools stay open?
They are two separate decisions. Student transportation consortia decide whether buses can safely run the routes; the school board decides whether the building opens. Boards keep buildings open so students who can get there safely still have school, and because a closure has to be made up later while a cancelled route does not.
How cold does it have to be to cancel buses in Canada?
Most consortia use a wind chill cutoff around −35 °C to −40 °C, with no snow required at all. Prairie and northern boards sit at the colder end of that range because families and stops are equipped for it; boards further south pull buses sooner.
Which Canadian province closes schools most often?
Atlantic Canada, and Newfoundland and Nova Scotia in particular. It is not because they get the most snow but because storms arrive with temperatures sitting at the freezing mark, producing rapid changeovers between snow, freezing rain and rain that are far more disruptive than a clean snowfall.
Does this work in centimetres?
Yes. Canadian pages default to metric, so snowfall shows in centimetres, temperature in Celsius and wind in kilometres per hour. Switch to imperial in the form if you prefer.
What time are Canadian cancellations announced?
Consortia patrol the roads before dawn and usually post between 5:30am and 6:30am, and boards announce closures in the same window. If nothing has appeared by about 6:30am, buses are running and school is open.
One Important Caveat
This is an estimate for planning, not an official notice. Only your board can close a school and only your transportation consortium can cancel buses. Always check their websites or local radio before assuming anything — and never make a travel decision based on this page instead of an Environment Canada warning.