I will start a four part blog (once per week) on White Christmas probability forecast for Ontario with the final part out around Dec.21-22nd.
Why the white Christmas obsession?
Anybody who knows me, knows I am a big Christmas fan; Father Christmas as I am known in the family. I often mention to the kids that when I die they should bury me in Christmas town so I can hang out with Bing Crosby, but not this Christmas town….
More like this one….
I as a child I mostly grew up in Timmins, Ontario. Northern Ontario is certainly known for its snow, back then snow at Christmas was a guarantee. Looking back at the stats for Timmins from 1970 – 1990, not one single year featured a green Christmas (1979 came close with only 3 cms). In fact, you would be hard pressed to find a year with no snow at Christmas, they have come close a couple times, but the average is usually 30 – 40+ cms. So not sure I associated a fun Christmas with lots of snow but it certainly started my obsession.
From a folklore perspective, a white Christmas is ingrained in our modern definition of Christmas, from the songs, movies, pictures and stories. Not only did Bing Crosby singing about dreaming of white Christmas in a war torn Europe in his movie, it goes even farther back to some of the 1800’s writings of Christmas traditions. Charles Dickens is known to many as the Father of modern Christmas traditions with his portrayal of a snowy and cold Christmas in “A Christmas Carol”. You might wonder how England could be the backdrop for a cold and snowy December when it’s climate is more akin to Vancouver weather than cold and snowy. The most likely fact points to Charles early life; born in 1812 in England, it was noted that he spent his first 8 years with a white Christmas. This was because the planet was in a period of cooling from the year 1300 – 1850, known as the “Little Ice Age” (More about it here: https://en.wikipedia.org/wiki/Little_Ice_Age ). Not only Dickens’s stories but a great deal of other Christmas traditions were born in the 1700 – 1800’s. This denotes that northern Europeans, as the migrated to North America, would have passed down memories and dreams of a white Christmas to their children that would pass on the traditions.
The White Christmas forecast
So this is certainly a very early look. Nobody can really predict storms this far out with any great deal of accuracy. All it takes is one good, or one bad storm to change it all. These storms cannot be seen that far in advance, even the computer models wont be able to pick up without more guidance on the upper atmosphere conditions as we get closer.
What we can take a look at is the general pattern. Keep in mind even this can be wrong when we are talking this many weeks out. Guidance from the long range Euro “weeklies” ensemble models are about the best at picking up on patterns.
We certainly see that Arctic air that is out west will makes it’s way into Ontario by Dec.10 through to the 18th of December. This will be a key time to pick up snow if storms can cooperate on their track. This will also be a great time for the Lake Effect snowbelt regions to pick up on a lot of snow as the Arctic air will be moving across the very warm great lakes.
After December 18th is where things might get questionable to maintain snow cover. The Arctic pattern looks to retreat back west and a more Pacific relaxed pattern looks to take hold. This means the jet stream may stay neutral across Canada and bring warmer air with it. That could mean normal high temperatures may go above by 3-5 degrees. Since our normal will be near -2c near the end of the month a temperature near +3 -4c can still keep snow on the ground as long as storms that bring rain can stay away.
Here is my map for the chance of white Christmas across Ontario as it looks right now. The map means a chance of snow on the ground at Christmas, not actually snowing on Christmas Day. Remember Environment Canada’s definition of a white Christmas is 2 cm or more on the ground:
I will update this map next Sunday.