✔ 最佳答案
I can say with almost 98% certainty that there will be snow on October 31st SOMEWHERE in Canada. Canada spans five time zones, and part of it is located in the Arctic circle. So odds are good that we would have snow.
However, most of the Canadian cities are located within 250 miles of the southernmost border (the one along the 49th parallel that borders USA) and snow in those cities is a litte more unclear.
You really need to narrow it down a bit more and give us an idea of the city, or at least the province, that you are concerned about for snow.
Attached below is the Weather Network Canada website link for Montreal. We are expecting the temperature to drop right before Halloween, and there is a chance that it will snow. But the odds of any accumulation that actually stays around is minimal.
In my 40 years here in Montreal area, I cannot remember more than twice when we actually had snow on the ground Halloween night. It is more likely to have a very cold rain, which in my opinion would be worse! It reduces visibility for drivers that have to watch out for kids, and it can ruin some costumes and make for some shivering and sick little children if parents are not careful.