Southern Ontario: ‘Snow Day’ Forecast for Friday, December 12, 2025
/Snow squalls that remained locked in place east of Lake Huron and southeast of Georgian Bay brought a second straight snow day to many students across the snowbelt, with school buses cancelled both Wednesday and Thursday. But for anyone hoping to turn this into a rare three-day streak and stretch the weekend a little further, the chances are not looking nearly as promising.
Through Thursday evening, the squalls have already begun to weaken, with intensity dropping off compared to earlier in the day. That downward trend is expected to continue overnight as winds ease and the lake effect snow machine gradually winds down. By morning, conditions should look much calmer, at least in terms of new snowfall.
However, despite the improvement in weather, many communities have spent the past 12 to 24 hours getting buried in persistent snow squalls. Road crews will be working hard overnight, but in the hardest-hit areas, it is unlikely that every rural route will be fully cleared by the time the morning bus run begins. Even without active squalls on Friday morning, the snow already on the ground may be enough for some school boards to consider keeping buses off the road for a third day.
Confidence in widespread cancellations is not particularly high, so we have capped the maximum at a 50 percent chance. This zone includes Huron County under the Avon Maitland District School Board, southern Bruce County within the Bluewater District School Board, and the Simcoe West zone under the Simcoe County District School Board. These regions experienced the most persistent squall activity today, and their large number of rural routes increases the likelihood that cleanup may not be fully completed by morning.
Outside this core area, a slight chance (25 percent) has been assigned to several surrounding regions. This includes Middlesex and Oxford counties within the Thames Valley District School Board, Perth County for AMDSB, the remainder of Bluewater, including northern Bruce County and all of Grey County, as well as Simcoe Central and Simcoe South. While buses should be able to run in most of these locations, the final decision will depend heavily on how effective overnight cleanup efforts are. Simcoe’s Central and South zones are also more urban, and historically, these areas require more severe conditions before cancellations are considered.
For the remainder of Southern Ontario, a snow day on Friday appears unlikely. Most regions fall into the very low to low category, with no significant weather expected overnight or Friday morning that would normally prompt cancellations. Unless there are unexpected localized issues left behind from today’s squalls, most students should plan for a regular school day.
Disclaimer: Instant Weather has zero authority when it comes to bus and school closures.
It is completely up to the school boards, bus companies, local authorities, and parents to decide what is best for their children. This is our best guess based on our forecast.

