A few years ago I took an Athabasca University course in Intermediate Composition. This was in 2009 while I was living in the city of Edmonton. I recently thought that it would be interesting to convert some of my class assignments into blogs such as this one:
The weather in Edmonton, Alberta – where I currently reside – is very distinctive when compared to that in other cities where I have lived. The differences are particularly noticeable when compared to my home-town of Vancouver, British Columbia. Almost everyone in Canada has heard of Edmonton’s extremely cold winter climate. Though an even more unusual aspect to the local climate might be just how quickly the weather can change. Back in Vancouver the weather sometimes stays almost the same for days at a time. Even though the Edmonton weather changes rapidly in short time periods, this area has little geographic variability. When it is cold and snowing in Stony Plain, it is likely to be cold and snowing in Sherwood Park. In a place with more geographic variety – such as Vancouver – the weather varies within a short distance even while it changes relatively slowly over time.
The Environment Canada web site [1] provides many interesting statistics. There we find that last winter at 3 AM on January 22, 2009, the temperature at the Edmonton International Airport was -7.2°C. By 3 PM that afternoon it was 12 degrees colder and then by the very next morning it had fallen to -36°C. That was a 29 Celsius degree temperature drop in just 36 hours! While the weather was also particularly cold at that time in Vancouver; there the high and lows for the entire week varied by just 15 degrees. Vancouver is famous for its winter rain but that tends to come down in a slow steady drizzle instead of cloudbursts. The city’s one-day extreme rainfall record of 89.4 mm arrived on Christmas Day 1972. Even though Edmonton is not famous for its rainfall, the comparable record of 75.6 mm, which arrived on mid-summer day in 1990, is not a great deal less.
When I was much younger I got a job working outdoors just south of Edmonton at Nisku. There I was surprised to see the many weather changes in a single summer day. When the rain starts in Vancouver, workers don their rain gear and return to work because they know the precipitation can continue for days. When it rained in Alberta I was surprised to see the outdoor workers take an indoor break since they expected that the wet weather would stop very soon.
Edmonton is in a flat plain and has little weather variability over distance. While there are a few low hills, the elevation only drops a hundred metres from the Edmonton International Airport to the depths of the North Saskatchewan River. It takes more than an hour to drive the hundred kilometres from St. Albert to Vegreville, yet the elevation at the destination is only 36 metres lower than at the start. The average weather varies little over a quite large area. For example, according to Environment Canada, the average temperature for the entire month of May varies by less than 2/10 of a degree from Camrose (10.7°C) to Athabasca (10.6°C) to Vegreville (10.5°C).
Edmonton is far from the influence of the mountains or the ocean. Unlike in Calgary, there are no Chinook winds roaring down from the Rockies to create a micro-climate and melt mid-winter snows. Here the weather seems more influenced by vast province-wide bands of clouds or sun with few hills to stop the onslaught. On local weather forecasts the predicted daily temperatures vary little over a wide area centred on Alberta’s capital city.
Edmonton’s continental climate variability is especially impressive for someone like me, who has moved from the coastal climate of British Columbia. There the weather is moderated by the sea. In the winter, when clouds often block the sun and winds blow in from the temperate Pacific, the Vancouver area can go many days without the temperature varying by more than a few degrees. In mid-summer it is not unusual to go several weeks without any sign of rain. Thunderstorms are quite rare. In Vancouver I lived for many years in apartment buildings overlooking the sea. Now I rent an eleventh floor apartment in Edmonton and I probably saw as many thunderstorms here last summer as the combined total of all my years in British Columbia.
The all-time record high temperature at the Vancouver Airport is 33.3°C and the all-time record low is -17.8°C. (Environment Canada) Edmonton International’s official range of extreme high and low temperatures is more than 30 degrees wider! Of course, coastal British Columbia does get occasional fierce wind storms but tornadoes are quite unheard of. Vancouverites still discuss the relatively small and quite unique Typhoon Frieda which struck way back in 1965 even though there was little building damage and just one death.
What Vancouver lacks in weather variability measured over time, it makes for great variability over short distances. The region has several quite distinct micro-climates. I have spent many summer hours lazing on the sunny beaches of Vancouver while watching clouds build up nearby on the mountains of the North Shore. From those same mountains it is less than 50 km south to the American border, yet the annual rainfall near the border is less than half the amount recorded in the mountains. The temperature, rainfall and snowfall on the coast vary greatly according to the distance from the ocean or the elevation above sea level.
There are many tropical locations where weather shows even less seasonal variety than that found in Vancouver. An example is Singapore where the all-time record high of 36°C is only 17 degrees greater than the all-time record low. (Herrera) Thus the most extreme recorded temperature change there is less than Edmonton can change in single day! But among locations outside of the tropics, Vancouver is noteworthy for its placid weather; while there are few locations—and certainly few large cities—that experience quicker weather changes than happen right here in Edmonton.
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