In the last two snow dumps we got 67-70 cm… inches would mean over 5 feet nearly 6 feet!! 
I’ve been riding in the Ottawa area over 40 years. Boarding spaces are hard to find. I’m also not impressed with a lot of the barns or the horsemanship but beggers can’t be choosers. Ottawa is a huge geographic area so there can be a lot of travelling. You can fit Calgary, Toronto, Montreal, Edmonton, and Vancouver in the same geographical space!
It does get cold but it does get very hot and humid as well. Snow isn’t really an issue because if there is a storm it’s unusual if things close (a few things did last week- even with the big snow schools were not closed but the buses were cancelled) and everything is up and running definitely by the next day.
Most hunter/jumper shows are held at Wesley Clover Park. In August they have the Longines Major League show. I believe there are 6 gold shows and about 8ish Trillium shows. You can also go schooling there when there’s a down time. Westar holds their Trillium show at their facility, and they try and make it fun.
Costs are comparable to the rest of the province. Board without training is available. Where I am my coach comes in and there are other boarders that have other coaches come in.
One of the downsides to Ottawa in terms of jobs is the French requirement. It is much more difficult to find a job if you aren’t bilingual even if it turns out you never actually use French on the job. Jobs are there but the job search is harder.