So the past Friday brought the rude arrival of winter with over 11 centimetres of snow catching many of us off guard without our winter tires on our automobiles. It was three weeks earlier (December 4) than the first winter storm of 2014. It has started discussions about how severe the winter of 2014-15 will be – will PEI receive more snow than last year, the worst in 42 years? Well, here is what the experts say.
Normally, a PEI winter (the months of December, January and February) averages -6 degrees Celsius and receives about 41 centimetres of rain and snow. Environment Canada uses climate models to forecast seasonal weather. Climate models are mathematical equations strung together that describe the physics and chemistry of the atmosphere. These equations are calculated using the largest computers in the country, known as supercomputers. Environment Canada forecasts the winter of 2015 to be above normal or “warmer and wetter”. I must mention, however, that Environment Canada’s seasonal forecast models are accurate for Prince Edward Island only 40-50% of the time (which is not significantly better than chance, meaning flip a coin and you’ll have the same odds of getting the forecast correct). Environment Canada’s seasonal forecasts are accurate in Northern Quebec, the southern Yukon and Baffin Island, but here on PEI, not so well.
We all know people who swear by almanacs when forecasting the seasonal weather, so I took a look at four of them. The 2015 Canadian Farmers Almanac forecasts the winter of 2015 as “wintry temperatures, very wet and white”; the 2015 Harrowsmith’s Canadian Almanac says the winter of 2015 will be “drier and milder than normal”; and the 2015 Harris’ Farmer’s Almanac’s seasonal forecast for the winter of 2015 is slightly warmer and slightly drier than normal. The 2015 Old Farmer’s Almanac, the one we are most familiar with as it has been forecasting seasonal weather since its first issue in 1792 (the time of George Washington’s presidency), uses a “secret formula” kept tucked away in a black tin box at the Almanac offices in Dublin, New Hampshire. The Old Farmer’s Almanac makes claims of 80% accuracy of their results, but studies of their forecasts show no better over the long-term than about 50%. The Old Farmer’s Almanac forecasts the PEI winter climate of 2015 to be “mild and dry”.
My own research at the University of Prince Edward Island that examined 140 years of weather observations here in Charlottetown has shown that the climate has definitely gotten warmer and drier, especially over the past 10-15 years or so. And that’s where I put my forecast for the winter of 2015 – to continue the trend and be “warmer and drier”.
Climate is variable, though – it goes up and down – as last year reminded us all too well. Climate is nature’s merry-go-round so it is often difficult to predict the coming season even with supercomputers, secret formulas or historical trends. To emphasize this point, I flipped coins to see what Lady Fortune’s forecast for the winter of 2015 will be – the result being “warmer and drier”. So there are many forecasts made but only one will be correct. Most predictions are for a warmer and drier than normal winter for PEI. I can sure support those predictions, but we’ll have to wait over three months to see who is right.
Predictions of PEI Winter 2015 | ||
Source | Temperature
Warmer (+) Colder(-) |
Precipitation
Wetter (+) Drier (-) |
Environment Canada | + | + |
Canadian Farmer’s Almanac | – | + |
Harrowsmith | – | – |
Harris’ Farmer’s Almanac | + | – |
Old Farmer’s Almanac | + | – |
Fenech | + | – |
Chance (Flip a Coin) | + | – |
. October 2014 turned out to be warmer and drier than normal – the ‘climate normal’ being the average of 30 years of daily observations from 1981 to 2010. During the month of October 2014, the average temperature in Charlottetown was 2.4°C warmer than the climate normal of 8.3°C; and 11 millimetres (mm) or 10% drier than the normal precipitation of 112 mm. The Climate Research Lab observing stations at Winsloe South, Flat River, Orwell Cove, Foxley River, Dingwell’s Mills, Argyle Shore and Cardigan Head all recorded measurements that were warmer and drier than normal during the month of October.
Questions? Contact Adam Fenech at afenech@upei.ca or (902) 620-5220