versus: How cold is the Edmonton International Airport?

Spring has arrived, and now the last thing that anyone wants to think about is winter. But there is one last thing that I wanted to look at before winter becomes a distant memory.

A few years ago there was a huff over the fact that the media typically only reported temperatures from the International, even though Edmonton itself is not that cold. And the temperature at the International does occasionally inspire headlines like "2nd coldest place on earth!" or "Coldest place in North America", so maybe that is a fair complaint? (on the plus side, we don't often get compared to Mars the way that Winnipeg does)

These are the average High and Low temperature for the Edmonton International Airport, and for the Edmonton Blatchford weather station which is located near the downtown.

The results are similar to what we saw when looking at other nearby rural Alberta weather stations. The High temperatures are quite close for Edmonton and for the International, but for the Low temperatures there is a gap of around 2-3°C.

The temperatures are increasing, with the trend for the Highs showing an increase of 0.6°C per decade for both stations. The Low temperature for Edmonton is also increasing by 0.6°C per decade, while the Low for the International was only up 0.4°C per decade.

Here we have the number of winter days above 0°C and below -20°C.

And again, similar to what we saw with the rural stations the International has about as many warm days each winter as Edmonton does. For the days below -20°C though, in some years the two stations are within a few days of each other, but in others the International has more than twice as many cold days as the city. For the winter of 2015-2016 it was 6 days below -20°C in Edmonton compared to 25 at the International.

And the very cold days are similar. The International frequently sees 10 or 20 days below -30°C each year, where Edmonton will have 1 or 2 or often none.  And it has been over 40 years since a day below -40°C was recorded in Edmonton, but the International still gets those every few years.

Looking at all of that, it seems like the High temperatures and the warm days aren't very interesting. So for the rest of this post I'll just focus on the cold days, and instead of going all the way back to 1960 we'll stick with the more recent history back to 1997.

Here we have the low temperatures for the International compared to each day's low temperature in Edmonton. And we can see that the International is generally a little colder. For some examples:

• 0°C in Edmonton: about -3°C at the International, with a range of 0°C to -5°C
• -10°C in Edmonton: about -13°C, with a range of -9°C to -18°C
• -20°C in Edmonton: about -24°C, with a range of -20°C to -30°C

To make a bit more sense of all of those datapoints, here is the average temperature difference between Edmonton and the International.

It's interesting that when Edmonton is between 0°C and -20°C, the International is typically only about 3 to 4°C colder. But once the temperature drops below -20°C that gap gets much larger, reaching 8 to 9°C on the very coldest days.

A problem with this chart is that for the coldest temperatures there aren't very many results, and so the "averages" are really just extremes or outliers. That is the reason that the line jumps around below -30°C. But thinking about those rare occasions when Edmonton claims the title "The 2nd coldest place on earth!" maybe the outliers and the extremes are the place to look.

Here are the International Airport's 100 coldest days since 1997, and the corresponding temperatures in Edmonton. I think this one gets to the heart of the issue.

On those really, really, really cold days, Edmonton is typically 8 to 9°C warmer than the airport. That's still cold, but it's arctic rather than martian. Of those 100 days there were 24 when Edmonton was actually 10°C or more warmer than the International, and only 3 when the difference was less than 5°C.

So just how cold is the Edmonton International Airport? Well, for most of the winter it's just a few degrees cooler than Edmonton. But when it gets cold, it gets really cold. Remember to plug your car in.

Update: If you'd like to know even more about the International Airport, I've done a followup to this The Edmonton International Airport: Part 2 which takes an even closer look, and which includes a comparison to airports in Calgary and Winnipeg.