2021/02/01

January 2021 Review

It seems like a long time ago now, but January 2021 started off pretty warm, and continued from a pretty warm December. But then things changed, of course. So let's take a look back at how warm it was, and how cold it got.


High Temperatures

Here we have January 2021's Highs, which were all above average and mostly above 0°C until January 22nd. Then for the final week things took a dip into the below-average range.

For the month as a whole we had 9 Highs below average compared to 22 above. On January 6th we had a warmest-in-30-years High of 6.6°C, and that was the only time that we got close to the top or bottom of our typical range. During this warmspell we were always at least a few degrees away from setting any new records.


Here we have the history of January High temperatures going back to 2000. Pink squares are for days with Highs above freezing, and 2021 had a fair number of pink squares.

On average in January Edmonton will have 12 Highs above freezing, and 2021 was a bit above that with 17. In recent years 2012 also had 17, and 2001 had 25. 2021 had 4 Highs hit 5°C, and that's right on the average. The last time that we hit 10°C in January was January 28th 2016 at 10.2°C.

The month started with a string of mostly-pink days, and then cooled of with 4 Highs which hit -15°C, and the coldest on January 25th at -16.9°C. That's quite a difference from last January which had 4 Highs hit -25°C, including a High of -29.7°C on January 14th, 2020.


Low Temperatures

January 2021's Lows look similar to the Highs, with 21 above-average Lows followed by 9 below-average. On January 20th we hit a warmest-in-30-years Low of -4.1°C, but other than that no days came close to the top or bottom of the typical range.


We did end up with 6 Lows hitting -20°C, compared to a January average of about 8. We didn't hit -25°C though, with the coldest Low of January 28th at -23.9°C.

Think back to 2020 again, last January had 8 Lows hit -25°C, including 4 hitting -30°C, with the coldest at -37.6°C on January 15, 2020.


For the winter so far we have had 7 Lows hit -20°C, compared to an average of about 15 at this point in the winter. We are now through the peak of our -20°C season, but there is still plenty of time left for stragglers to show up in February and March. In a full winter we average around 23 Lows at -20°C, including 10 at -25°C.


Here we have the number of late-winter -20°C Lows each winter, from February 1st onwards. 5 more -20°C Lows would probaby be pretty typical, but some years like 2016 had none, while 2019 had 25. 

For the number of -25°C Lows in a winter it's the luck of the draw between none, a few, or a year like 2019 which had 19 of them.

Warm & Cold Months

Even with the cool end to January 2021, its average temperature still ends up well above the 20th century average for January, and as a big orange bubble in our chart of monthly bubbles. That follows a warm December 2020, and it is also the latest in a long line of orange Januarys.

January 2020's extreme deepfreeze pushed it down to a small orange bubble, but the last time that we had a January which was colder than the 20th century average was 2004.


January 2021 ends up with an average High of -2°C for the 17th warmest on record. The average Low of -10.8°C was the 10th warmest.


December & January

January 2021 followed a warm December 2020, and the two months together had the
an average High of 0.8°C, for Edmonton's 7th warmest December-January Highs. The average Low of -9.9°C was 6th warmest for December-January Lows.


"Warm" Januarys are pretty typical nowadays, with our average temperatures up roughly 10°C from where they were a century ago (or even in the 1960s). For December though, while December 2020 was quite warm the month of December has not generally warmed up as much as January has, increasing by only 3~5°C. And so while January used to be our coldest month by far, in the past decade its average temperatures (in turquoise) have caught December's (in dark blue).


Across Canada

January 2021 wasn't just warm in Edmonton, but was warm in cities across the country, and particularly on the prairies. That followed a warm December 2020, and also a warm November 2020 (except in Edmonton where it was pretty meh).

In this dashboard there is data for 9 Canadian cities: Vancouver, Edmonton, Calgary, Regina, Winnipeg, Toronto, Ottawa, Montréal and St. John's.

If we add up the temperatures for all of those cities for November 2020 through January 2021, it turns out that this has been a very warm November-January. The Highs were the 3rd warmest on record after 2011-2012 & 2005-2006. The Lows were 2nd warmest after 2005-2006. 

In Edmonton we didn't get the warm November, and so this was only our 11th warmest November-January on record.


Snowfall

Snowfall at the International Airport in January was 10.2cm, and that's only about half of January's average of 22cm. That follows 3.4cm in December, which was a bottom-5 December. 


With October, December and January all below-average for snowfall our total so far this winter is 49.5cm, and that is below the average of 68mm.


Looking across the country Edmonton's 49.5cm of snow this winter is below everyone else, except for Vancouver. St. John's is up at 120cm, Calary & Montréal are above 90cm, Ottawa is at 78, Toronto is at 66cm, and Winnipeg is at 55cm.


Snowdepth

Even with the warm temperatures during December & January neither Blatchford nor the International saw much of a drop in snowdepth. Both stations have been hanging around the 18cm mark since early December, with the recent snow bumping that up over 20cm. During the mid-winter a depth of 20-25cm is right around average.


Looking at the snowdepth across the country Edmonton had been pretty alone at around 20cm for most of the winter. But starting in mid-January Montréal, Ottawa & St. John's all finally moved up past 30cm. There is still about a month-and-a-half left in the snow season, and for Edmonton that might be 2 months (or 2 1/2 for a winter like last year).


February Temperatures

Looking ahead to February the temperatures are often a lot like January, with 10-15 Highs above 0°C, and 5 Lows below -20°C. On average February has the lowest snow of the main winter months, at about 14cm.

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