Eastern Ontario · In centimetres
Snow Day Predictor Ottawa
Will school be closed tomorrow?
Loading Ottawa's live forecast now. Tuned for what actually closes schools here — large system storms and deep cold.
Ottawa Closure Chance
In Ontario a bus cancellation is the likelier outcome — check the bus cancellation predictor for that.
What Closes Schools in Ottawa
Ottawa has one of the highest snow tolerances in Ontario. It averages more than two metres of snow a season, it is equipped accordingly, and it runs normal school days on amounts that would close boards in the southwest.
Ottawa's snow arrives mainly from organised system storms tracking up the St. Lawrence valley rather than from lake-effect squalls, which makes it more forecastable than snowbelt cities — when a big storm is coming, it is usually visible a day or two out. The city also runs a large rural fringe east and south, where routes fail well before anything downtown does.
What a Bad Morning Actually Looks Like
A bad Ottawa morning takes real weight. Thirty centimetres overnight from a storm tracking up the valley, still falling at 6am, with rural routes out toward Osgoode and Cumberland drifted in. The city itself is usually moving by then, which is exactly why closures are so rare and cancellations so often rural-only.
How Much Snow It Takes Here
Bus cancellations generally need 20 cm or more, and closures are genuinely uncommon. Deep cold is a separate trigger: Ottawa reaches −35°C wind chill most winters, which pulls buses with no snow involved.
Ottawa needs a large event before depth matters, so watch the storm track rather than the hourly timing. When one does arrive, snow still falling through the morning is what turns a rural cancellation into a closure. Beyond that, snow still falling between 3am and 8am counts for several times its depth, because the pre-dawn road patrol is what the decision is built on.
In Ottawa, Expect the Buses to Go First
Ontario boards rarely close schools. What happens instead is that the student transportation consortium cancels buses while the building stays open for anyone who can get there. They are two separate decisions, made by two separate organisations, on different criteria, and announced separately.
So on a bad Ottawa morning the honest answer is usually: no bus, but school is running. If that is your real question, the bus cancellation predictor weighs blowing snow and open rural roads far more heavily, because that is what actually pulls buses.
Ottawa's transportation covers a genuinely large rural fringe alongside one of the densest urban cores in the country. Rural zone cancellations with the city running normally are the standard outcome, and the two are announced separately.
Nearby
Snow squalls and drifting are intensely local in Ontario. If you are near a boundary, it is worth checking more than one:
Ottawa Snow Day Questions
Will school be closed tomorrow in Ottawa?
The predictor above loads Ottawa's live forecast and scores it against what actually closes schools here. In Ottawa the main driver is large system storms and deep cold. Set the day to Tomorrow to check the next school morning.
How much snow closes schools in Ottawa?
Bus cancellations generally need 20 cm or more, and closures are genuinely uncommon. Deep cold is a separate trigger: Ottawa reaches −35°C wind chill most winters, which pulls buses with no snow involved.
Are buses cancelled in Ottawa when school stays open?
Frequently. Across Ontario the transportation consortium and the school board make two separate decisions, and the buses are pulled far more often than the schools close. On a bad Ottawa morning the usual outcome is no bus but school still running.
What time are Ottawa cancellations announced?
Ottawa announcements are posted by about 6:00am. Big system storms are sometimes called the evening before, because the track is known well in advance.
Why does Ottawa almost never close schools?
Because it averages over two metres of snow a season and is equipped accordingly. The fleet, the salt budget and the drivers are all built for it. Amounts that would close a board in southwestern Ontario are an ordinary Ottawa Tuesday, so a closure needs something genuinely exceptional.
Does this work in centimetres?
Yes. Ontario 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.
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.