Brockville Snow Day Predictor – Upper Canada DSB and Catholic DSB of Eastern Ontario
Will Tomorrow Be a Snow Day?
Canada's most accurate snow day predictor
Brockville sits on the St. Lawrence River in Leeds and Grenville counties, in eastern Ontario between Kingston and Cornwall. The city averages approximately 180–210 cm of snow per year and shares the Upper Canada District School Board (UCDSB) with Cornwall. Its St. Lawrence Valley location exposes it to valley storm systems and Alberta Clippers, while the board’s rural Leeds-Grenville territory makes rural bus routes a key closure factor.
Will Brockville schools be closed tomorrow? Enter your city in the predictor above for tonight’s closure probability, updated hourly from Environment Canada data. Always confirm with your school board’s official channels before making plans.
Brockville School Boards – Who Decides Closures
- Upper Canada District School Board (UCDSB) – Brockville, Cornwall, and eastern Ontario (Leeds-Grenville, SDG). ucdsb.on.ca | Announces: by 6:00 AM | Radio: 104.9 JRfm, Corus Brockville | Twitter/X: @UCDSB
- Catholic District School Board of Eastern Ontario (CDSBEO) – Catholic board for eastern Ontario. cdsbeo.on.ca | Announces: by 6:00 AM | Twitter/X: @CDSBEO
Brockville Snow Day Triggers – What Closes Schools Here
Brockville’s closures are driven by:
- St. Lawrence Valley storms: Systems tracking up the St. Lawrence Valley bring heavy snow and mixed precipitation to the Brockville area.
- Alberta Clippers: Fast northern systems deliver quick, intense snowfalls through eastern Ontario.
- Rural Leeds-Grenville drifting: The UCDSB’s rural bus routes north of Brockville close for drifting on open eastern-Ontario roads.
How Often Do Brockville Schools Close?
The Upper Canada DSB’s Brockville-area schools close approximately 5–8 days per year, with rural bus cancellations more frequent. December through February are peak months.
See Also – Nearby Predictors and Guides
Explore the Ontario Snow Day Predictor for all school boards in the province, or check nearby cities:
Related guides:
Frequently Asked Questions – Brockville Snow Days
Which school board and bus system does the Brockville predictor track?
The predictor calculates data for the Upper Canada District School Board (UCDSB) and the Catholic District School Board of Eastern Ontario (CDSBEO). The official transit authority it simulates is the Student Transportation of Eastern Ontario (STEO).
Why does the Brockville predictor show a high percentage when city streets look safe?
Brockville sits within a massive regional transport boundary that includes expansive rural areas across Leeds and Grenville. The predictor calculates risk for the entire zone, meaning that blinding snow, heavy drifts, or black ice on open rural county lines outside town limits will cancel buses for Brockville schools even if the main streets inside the town are salted and clear.
How much snow is required to trigger a high percentage on the Brockville predictor?
Because Eastern Ontario is well-equipped for winter, standard snowfall rarely triggers a cancellation. The predictor’s algorithm spikes sharply when a weather warning forecasts 15 to 20 cm of rapid accumulation right before the morning commute, or when severe freezing rain warnings threaten to glaze major corridors like Highway 401.
If the Brockville predictor hits 100% and buses are called off, do schools close?
No, schools almost always stay open for walking students and staff even when buses are cancelled. However, a maximum predictor percentage helps parents prepare for “inclement weather days” where regular curriculum delivery is officially paused, and all scheduled tests, exams, or presentations are postponed.
What time is the Brockville snow day predictor most accurate?
The morning check between 5:00 AM and 5:30 AM is the most accurate window. While checking at 9:00 PM the night before provides a helpful baseline estimate, volatile winter storm tracks moving up the St. Lawrence Valley can shift rapidly overnight, requiring final morning radar updates right before the official STEO announcement at 6:15 AM.