Lyndsay Morrison, staff writer
November 24, 2010 — With another La Niña winter set to roar across Canada, The Weather Network takes a look back at the previous La Niña season of 2007 / 2008.
The official start of winter is less than a month away, and forecasters at The Weather Network are gearing up for an active season.
“We know we're going to see some active weather for the BC coast and also likely more active weather than we saw last year across southern Ontario and Quebec,” says Chris Scott, a meteorologist at The Weather Network. “This year, we think the big cities in Canada will have a better chance of seeing bigger storms.”
La Niña describes a large pool of water over the Pacific Ocean down by the equator that's below normal in temperature. The subtle changes in temperature have a dramatic impact on the air above the ocean, as well as the jet stream pattern, and the weather patterns around the world.
The most recent La Niña winter was in 2007 and 2008. Scott says that was a memorable winter for people living in western Canada.
“We saw active weather in BC especially just off the coastal elevations. There was quite a bit of snow, and a really good ski season as well.”
Snow levels were above average across much of British Columbia, but La Niña had an even bigger impact on people living in eastern Canada.
“This was an amazing winter in southern Ontario and Québec,” says Scott. “We saw record snow in some cases and storm after storm and it was amazing to watch. There was a lot of snow that fell in places like the GTA, Ottawa and Greater Montreal.”
Montreal saw over 370 cm of snow in the winter of 2007 / 2008, while Ottawa had to deal with over 430 cm. 190 cm of snow was dumped on the city of Toronto.
Those snowfall accumulations in the 2007 / 2008 La Niña season season started piling up on December 16th, 2007, when the eastern half of the country was hammered by an intense pre-Christmas storm. It dumped 20 - 30 cm of snow in most places, making it a nightmare on the roadways. For retailers, the storm couldn't have come at a worse time. It was the second last shopping weekend before Christmas.
The snow kept coming down in the months that followed. 76.8 cm of snow fell in the city of Toronto in February of 2008, making it the city's snowiest month this century. A major storm on February 6 dumped 30.4 cm - a one day snowfall record for the city this decade. A late season storm also resulted in hundreds of flight cancellations at Pearson Airport, just as families were taking off for March Break.
By the time 2008 came to an end, more than 1,000 mm of precipitation had fallen on Toronto, making it the city's wettest year on record.
Atlantic Canada normally doesn't get hit as hard by La Niña because of how far east the provinces are. The winter of 2007 / 2008, however, proved to be an exception.
The season roared into the Maritimes with back-to-back storms on January 1 and 2, dumping heavy amounts of snow in parts of New Brunswick. By the time winter came to and end, the community of Bathurst had set a new snowfall record. A staggering 509.1 cm fell between October and April - almost 70 cm more than the old record and 180 cm above normal.
So much snow fell in parts of New Brunswick that the province faced a salt shortage. Plow operators with pre-determined contracts were working overtime. In some rural communities, snow could still be found on the ground in June. The melting snow in the spring contributed to some of New Brunswick's worst flooding in decades.
Newfoundland also took a hit in the La Niña winter of 2007 / 2008. On St. Patrick's Day in 2008, the second of two powerful back-to-back storms roared across Newfoundland. In weather legend, a storm that hits around that time is referred to as “Sheila's Brush.” Schools were closed and buses were pulled off the roads in St. John's. Fogo Island declared a state of emergency because roads were completely block by snow. Gander saw 120 cm of snow - about a quarter of its annual snowfall in about a week.
Scott says the potential is there for some active weather in Atlantic Canada with this La Niña season, too.
“We do expect to see our share of storms, but one thing to watch out for is when storms track out of Ontario and Quebec they may track a little further north than they sometimes do. Which would let us off the hook for the really big snow storms.”
With the 2007 / 2008 La Niña filled with record-breaking snowfall in major cities across eastern Canada, the big question is: will the same thing happen this year?
“It’s unlikely we’ll see as much snow in these big cities as we saw three years ago,” says Scott. “But certainly La Niña winters often give you very active weather. We could still see a lot of snow, maybe just not as much as three years ago.”
For a closer look at what you can expect in your neighbourhood this upcoming season, be sure to check The Weather Network's 2010 / 2011 Winter Outlook.