AccuWeather.com, a U.S.-based weather forecasting service, is calling for average snowfall for the southwest coast of British Columbia this winter with slightly warmer temperatures.
According to their long-term forecast released last week, “The West Coast, including Vancouver, will have a changeable winter with drier-than-normal conditions for December before more typical winter storminess returns in January. Temperatures will average close to normal for the first half of the winter then trend above normal for the second half of the season. Snowfall along the Coast (Mountains) in British Columbia will be typical for an average winter with the greatest potential for heavy snowfall coming in January and early February.”
Meteorologist Brett Anderson, the lead Canadian forecaster at Accuweather, said the predictions are based on historical data and other weather trends. “What we do is look at the weather patterns so far this year in the northern hemisphere, the jet-stream pattern and that kind of thing, and then we look at every year for 50 years and look for similar springs, summer and falls. We break those years out and make them part of our analogues package,” he said. “In this case we have eight seasons in particular that seem to match up with this one.”
Anderson said that the data suggests the first part of the winter will see a strong high pressure system set up over the Gulf of Alaska, which will send most Pacific storms north and probably direct one or two cold snaps to Southern B.C. However, he says that dominant pattern should break down around January, opening the door for slightly warmer and wetter weather for the rest of the winter.
That’s not to say that Whistler isn’t going to get any snow in November or December this year. At least one of the analogues tracked by AccuWeather.com saw a massive snowstorm land in December, and harder-to-predict localized systems should contribute some snow as well.
“For us to predict that now is impossible, but it’s worth putting out there that one of the analogues we’re keying in on this year saw a significant December storm across southwest B.C. that went right down to the coastline,” he said. “Also keep in mind that this is a seasonal forecast and certainly there’s a lot of error with these kinds of forecasts. We’re probably accurate to about 55 to 60 per cent. It’s better than a flip of the coin, and the science has gotten a lot better in the last 10 to 15 years, but there’s still a way to go.”
Overall, Anderson said it was difficult to predict the weather this winter with no strong La Niña or El Niño wind and weather system influencing the forecast. Both systems can result in higher than average snow packs for Whistler.
Some of the trends identified by AccuWeather.com seem to be backed by Environment Canada’s seasonal forecasts as well.
Those forecasts use a probability system to determine temperature and precipitation in the long range and so far the data is leaning (albeit weakly) towards an average early winter for precipitation with a 20 per cent chance of there being more snow than normal and a 20 per cent chance of less snow.
The good news is that an average winter in Whistler still means more reliable snowfall than almost anywhere in North America. An average year sees about 11.74 metres, or 38.5 feet of snow per year.