Calgary's May long weekend weather is trash: A statistical analysis

Queen Victoria was born before Canada became a country and died before Alberta became a province, but her legacy looms large in the form of a holiday that is held up to this day as the official kickoff to summer — even though it rarely delivers on that promise.

For Calgarians, that's not just local lore. It's science.

Historical weather records show, more often than not, the weekend weather is cool — or downright freezing — and rainy, if not snowy.

That's not to say it's always bad. There have been the occasional years when the weather gods, in their infinite caprice, smiled down upon the people and granted them three consecutive days of sun and overnight lows that didn't leave frost on their tent flaps.

But those tend to be the exception. The rule, generally, is much gloomier for those itching to finally get outdoors after the long, harsh winter.

For people looking to get outdoors in the higher altitudes of Banff and beyond, it's even more rare to feel that summery glow.

Looking at historical weather records for the three consecutive days that form the modern long weekend — that is, the Saturday, Sunday and penultimate Monday in May — we can see the disappointment in data.

In Calgary, which had 140 years' worth of records available, only 15 per cent of May long weekends saw the high temperature exceed 25 C.

The average temperature, meanwhile, was below 10 C on 45 per cent of weekends, while the low temperature was below freezing 34 per cent of the time.

Banff, which has temperature records for 132 May long weekends, was even cooler, with only five per cent seeing the temperature rise above 25 C at any point.

Nearly three-quarters of long weekends in Banff had average temperatures below 10 C, while 70 per saw freezing overnight lows.

Not only do May long weekends tend to be defined by cool temperatures, they also tend to be at least a little wet — or snowy.