I grew up in the prairies, but lived 8 years in Ottawa, making the cross-country drive at least three times.
I love driving, so my notes below deal more with route selection than attractions. May is an interesting time to travel because spring has arrived for most of Canada, but winter storms are still possible in alpine areas. You could even take in a ski vacation in Banff.
Sunshine Village is open until at least Victoria day every year, and the resort experienced record-breaking snowfall this year.
Be prepared for long driving days in Ontario. Lots of lakes and rocks and trees... It bores me to tears. The most interesting bits we saw were Ouimet Canyon and the Terry Fox monument near Thunder Bay. There might be some interesting sites along Georgian Bay, but we always cut cross-country between Saulte-Ste-Marie and Ottawa.
Get the kids to pay attention as you drive from Kenora to Winnepeg -- the transition from rocks-trees-and-lakes to wide open prairie is quite abrupt.
I love the prairies. You can see for miles all around you, and the sky is huge. I love it, but many friends and family from 'out East' find driving through the prairies boring to the point of dangerous. Stop for breaks -- there are parks and playgrounds in virtually every town, not to mention countless "Historic Site" markers along the highways. Every city has it's unique attractions and charms. Calgary's Heritage Park is my favorite summer attraction. West Edmonton Mall is good year-round.
Don't be like my uncle and glance at a map of western Canada, thinking, "well, since Edmonton and Calgary are only a three hour drive apart, Vancouver must be just 5 or 6 hours from either city." Vancouver is 10-12 hours from Calgary, 11-13 hours from Edmonton, assuming weather is cooperative. In Alberta, four-lane highways extend west to Hinton and Lake Louise. In BC, four-lane highways go as far East as Kamloops. The highways in between are narrow, windy, full of wildlife and inattentive drivers. Stay alert.
To give you a sense of the length of the winter season in the alpine regions, BC requires all vehicles driving through the mountains to have winter tires or carry chains from October 1 to April 30. Should you use winter tires in May? No, but avoid mountain snowstorms if possible. Routes where alpine weather can be expected include Rogers Pass (Highway 1), Crowsnest (Highway 3), Yellowhead (Highway 16 / 5), Coquihalla (Highway 5), and Sea-to-Sky (Highway 99). May can be considered early spring in alpine regions. Pay special attention to highway conditions in BC if you plan to drive through the Rogers Pass / Highway 1 from Calgary to Kamloops (check
www.drivebc.ca). The Rogers Pass is notorious for heavy snow, winter avalanches, spring mud slides and weather-related traffic accidents. In the summer, when weather is perfect, Highway 1 is spectacular to see and drive. However, in May, storms can dump lots of snow, and extremely warm weather can cause snow-melt flooding and mud slides. From November to May, I suggest using the Yellowhead Highway (16 / 5) between Edmonton and Kamloops unless you are confident about Rogers Pass conditions. The Yellowhead route is primarily in river valleys, less prone to extreme weather. It has just a fraction of the road closures compared to Rogers Pass / Highway 1.
The Coquihalla Highway from Kamloops to Hope is steep (multiple sections of +20 km at 8-10% grade), spectacular, and prone to bad weather. But it's a well-maintained 4-lane highway. The alternative route is the Fraser Canyon, which is longer and slower, but avoids steep hills and alpine weather. There is also the Coquihalla Connector, which is one of the best ways to reach the Okonogan valley and the city of Kelowna. May might have excellent beach weather, but the Lake Okonogan will likely be too cool for swimming. North of Kelowna, Wood Lake might be fine, as it's a bit shallower and warms up faster. There are a huge number of wineries in the area, stretching from Vernon to the US border. For many estate wineries, tasting rooms tend to operate weekends only until Victoria Day. (If want a unique high-end wine experience, PM me and I'll help set up something special at my sister-in-law's winery.)
Attraction tip: There are hot springs all over BC, plus some in Banff, Alberta too. Each are unique, but you could easily work one or two into unique family adventures. BC Hot Springs list is
here.
Highway 1 from Hope to Vancouver follows the Fraser Valley flood plain -- it's perfectly flat for most of the route. From Abbottsford to Vancouver, it's prone to rush hour / long weekend traffic congestion, which can add as much as an hour to your travel time. "Pack your patience."
In Vancouver, I suggest checking out Grouse Mountain (check when their summer season starts) and Stanley Park. The Disney Wonder is in port May 20-21 only. But other cruise lines sail into Vancouver almost every day. It's facinating to sit on the Stanley Park Sea Wall and watch the cruise ships go under the Lions Gate Bridge (they typically sail in around 6 or 7 am, sailing out around 4 or 5 pm). The Port of Vancouver publishes a daily schedule
here.
If you're feeling adventurous and the weather is cooperative, you could drive the lengthy but very scenic Crowsnest Highway (#3), a southerly route connecting Lethbridge and Vancouver. The mountain passes are just as weather-sensitive as the Rogers Pass, but there is much less traffic. You will also pass through the unique dessert town of Osoyoos.
Another adventurous route is the Sea-to-Sky highway (#99). From Vancouver to Whistler, it's a very well-maintained 4-lane highway. From Whistler to Kamloops, it's a windy and steep mountain route with several one-lane bridges.
