How much snow closes schools in Canada

Parents ask for a number: how many centimetres close the school. Canada does not publish one number that we can cite, and this site will not invent one. School closures are local decisions. Education is provincial under section 93 of the Constitution Act, 1867 (Justice Laws). Boards and, in parts of Ontario, transportation consortia weigh roads, staff, and their own policies. A snowfall total is one input. It is not the decision.

This article says what we can measure, how those measurements differ across cities we actually publish, and how the predictor uses snow without pretending the formula is a board bylaw.

What we measured, and what we did not

City pages that show a snowfall table use the Open-Meteo archive of ERA5, daily snowfall_sum and temperature_2m_mean, from 1 January 2014 through 31 December 2023, at the latitude and longitude of that page's forecast point. The source is Open-Meteo. The table is a reanalysis at a point. It is not an Environment and Climate Change Canada climate normal from a station, and it is not a record of past school closures.

We do not publish a city unless that ten-year series returned enough data. We also skip a town when its totals are too close to another town we already publish in the same province. Near-duplicate pages would not tell a family anything the first page did not. The cities below are on the site because their numbers are not the same story.

The same country, different winters

These figures are the annual snowfall average at each forecast point, ERA5, 2014–2023:

Place	Annual snow	January mean	Largest month
Victoria	31.2 cm	5.2°C	February, 13.4 cm
Kamloops	37.7 cm	−2.0°C	December, 11.6 cm
Whistler	176.9 cm	−0.5°C	December, 60.7 cm
Calgary	95.2 cm	−6.4°C	see the city table
Winnipeg	89.2 cm	−14.2°C	see the city table
St. John's	228.2 cm	−1.9°C	January, 58.2 cm
Labrador City	272 cm	−20.9°C	November, 44.9 cm
Iqaluit	133.6 cm	−24.4°C	December, 20.7 cm

Read the rows across, not down a single column. Victoria's year is a small snow total and a January mean above freezing. Whistler, a few hours inland, has a December average of 60.7 cm and a January mean near freezing. Those are both in British Columbia. A sentence that said "British Columbia closes at X centimetres" would be false to this table and false to the way decisions are made.

St. John's and Labrador City are both in Newfoundland and Labrador. St. John's combines a heavy year (228.2 cm) with a mild January (−1.9°C). Labrador City combines a heavier year (272 cm) with a January mean of −20.9°C. The Newfoundland and Labrador hub says those two pages exist because the winters are not the same. NLSchools (nlschools.ca) is the authority we link. We do not claim either total is the amount that closes a school.

Iqaluit's January mean is −24.4°C while the annual snow total is 133.6 cm. Cold and snow are different factors. The methodology scores them separately. A family that only watches the snow column will misread a dry, very cold morning.

How the predictor uses centimetres

The published model converts overnight snow into points. The breakpoints, copied from the same constants as the methodology page, start at 0 cm (0 closure points), then 2 cm (8), 5 cm (26), 10 cm (51), 15 cm (71), 25 cm (87), and 40 cm (94), before a regional multiplier and a cap of 97. Bus points use a different table, because buses often stop first. Those numbers are our editorial scale. They are not a statute and not a board regulation.

The multiplier depends on the preload for that place. High snow tolerance multiplies snow points by 0.72. Low snow tolerance multiplies them by 1.25. Typical leaves them unchanged. A city page states which preload it uses and says that the preload is editorial. Victoria's low annual total is why a low-tolerance preload can be honest there. Labrador City's 272 cm year is why a high-tolerance preload can be honest there. We do not apply Victoria's preload to Labrador City.

Timing matters inside the window from 7 p.m. to 8 a.m. Snow that peaks between 5 and 7 a.m. is not the same as snow that ended the previous evening. The methodology page states the morning bump and the evening ease. A ten-year average cannot see that timing. The live score can, because it uses the hourly forecast. The average on the city page is context. It is not the score.

Freezing rain is not in the snow column

ERA5 snowfall does not answer an ice storm. The predictor reads weather codes for freezing rain and freezing drizzle, and it treats rain at or below freezing as an ice risk. Those rules are on the methodology page. A city with a small annual snow total, such as Victoria at 31.2 cm or Kamloops at 37.7 cm, can still have a morning that the snow column does not describe. The city pages say that in their own words. This guide repeats it so nobody turns the table into a rule.

Wind is scored only when snow or ice is already in the window. We do not add wind points to a dry, calm commute just because the map looks wintry.

What to do with a number

Use the city table to see what a normal year looks like at that point. Use the live gauge to see the next morning. Use the board, consortium, or school site to see the decision. Calgary, Winnipeg, Whistler, and St. John's can all show a different band on the same date. That is the forecast at each point, not a ranking of which city "deserves" a snow day.

If you need the official weather warning, use Environment and Climate Change Canada. We do not scrape that site, and we do not present ERA5 as a warning from the Meteorological Service of Canada.

More points from the same run

The same ERA5 series, still 2014–2023 at the forecast point, is what these pages use. They are listed because each one cleared the "not the same as a neighbour in this province" bar:

Place	Annual snow	January mean	Why it is not a copy of the nearest big city
Kamloops	37.7 cm	−2.0°C	Interior dry total, not Vancouver's 78.3 cm
Cranbrook	101.5 cm	−4.9°C	Between the dry valley and the mountain totals
Sydney	225.1 cm	−2.8°C	March is the largest month, unlike a midwinter peak
Charlottetown	196.3 cm	−5.0°C	February peak of 49 cm on the Island
Saskatoon	78 cm	−12.4°C	November leads; January is the cold, not the snow peak
Thompson	126.7 cm	−20.3°C	Colder January than Winnipeg's −14.2°C in this run
Whitehorse	99.7 cm	−11.4°C	Territorial point; we publish no Yukon board page
Yellowknife	75.3 cm	−23.2°C	Cold with a modest annual snow total

Vancouver's 78.3 cm and January mean of 4.3°C are on the Vancouver page. Whistler's December of 60.7 cm is why that mountain point is not filed under the Vancouver total. None of these rows is a closure threshold. They are the reason the pages are allowed to exist separately.

What we skipped on purpose

Dozens of towns were fetched and then not given a page. Their ERA5 snowfall and January mean were too close to a city we already publish in the same province. Markham is not a separate climate story from Toronto in this dataset. Kelowna is not a separate story from Kamloops. Publishing both would have been the same paragraph with a different name. We do not do that. The skipped list is a quality decision, not a claim that those towns never close.