The month started off with a weeks-long deepfreeze, which we looked at in detail in Deepfreeze 2019! That post is full of fun charts, and we won't repeat it all again here, but the highlights were:
- 18 Lows in-a-row which hit -20°C, making it Edmonton's 22nd longest streak since 1880.
- 9 Lows in-a-row which hit -25°C, for the 39th longest streak.
- 15 Highs in-a-row which hit -15°C, for the 31st longest streak.
- 18 Highs in-a-row which hit -10°C, for the 15th longest streak.
The last time that we saw a sustained deepfreeze like that was 1996, and they haven't been common since the 1970s. The records for the various deepfreezes were all set in January 1950 and January 1969, which were both two very cold months.
That was just the first few weeks of the month though. After that things got a bit warmer, but not a lot. So let's take a look at the whole month:
5th Coldest February Since 1880
February's average temperature was -19.4°C, which made it Edmonton's 5th coldest February since 1880. The average temperature for February during the 20th Century was -10.1°C, so this year we were 9.3°C below the longterm average. In recent years the average for February has been about -8°C, so we were 11°C colder than that.
The last time that we had a February this cold was 40 years ago in 1979, which was Edmonton's 4th coldest February with an average temperature of -21.4°C. And the coldest recorded February was 1936 with an average temperature way down at -27.3°C.
This February's High of -14.3°C was also the 5th coldest-since-1880. In recent years our average High for February is about -2.5°C, so this year was -12°C colder than that, and it was also colder than the average Low for February, which is about -12.5°C. The average Low for February 2019 was -24.4°C, and that ranked as the 6th coldest-since-1880.
29th Coldest Month
February's average temperature of -19.4°C also made this Edmonton's 29th coldest month overall since 1880.
The last time that we had had a month this cold was January 1982, with an average temperature of -21.8°C. And Edmonton's coldest recorded month was January 1950 with an average temperature of -27.8°C
Low Temperatures
The first 18 days of February were really cold, then things warmed up a bit (but still below average), and then it was really cold again.
The blue dots in this chart are the days with temperatures which were the coldest-since-1996, which is when data for the current Blatchford weather station starts. And in February we set 12 coldest-since-1996 Lows.
Even with the cold days we were still well, well above the record coldest-Lows which are mostly down around -40°C or -45°C.
In total February 2019 had:
- 4 Lows of -30°C or colder. In the past 20 years there had only been 2 other -30°C days in February, in 2018 and 2008.
- 16 Lows hit -25°C. In recent years 2014 had had the most, with 6.
- 21 Lows hit -20°C. In recent years 2011 had had the most, with 15.
- Compared to 1919 (over on the right side), 2019 had 1 fewer -30°C Low than a century ago, but 6 more -25°C and -20°C Lows.
During an entire winter we average about 23 Lows which hit -20°C. That ranges from an El Niño winter like 2015-2016 with 6, to a cold winter like 2010-2011 with 48.
This winter by the end of January we had had only 5 -20°C Lows, so it had been a pretty mild winter. But then in February we had 21, which is basically a winter's-worth of cold days in a single month.
We also average about 8 -25°C Lows each winter. This February we had 16, so that was two winter's-worth of really cold days packed into 28 days.
And those 4 -30°C Lows? The last time that we had a month with 4 -30°C Lows was January 1997, and then right before that in December 1996. That last time that we had a February with 4 -30°C Lows was 1979, which had 6.
High Temperatures
Normally we start these monthly reviews by looking at the High temperatures, but this month they aren't quite as interesting as the Lows were. The Highs this month were almost all well below average, with 9 coldest-since-1996 days.
During the winter months - December, January, February - I always like to mention that we will usually get at least a week of warm days, with temperatures of 0°C, or 5°C, or more. But that was not the case this February. February 22nd hit 0.0°C, and that was it.
In recent years the least-melty February had been 2014, with 3 Highs of 0°C or more. But the average is 12 warm days, and even back in 1919 there were 8.
This year we also had one High way down at -26.9°C on February 3rd. That was the coldest February High since 1989. We also had 8 Highs of -20°C or colder, and that hadn't happened since 1979 with 9.
February 22nd hit 0.0°C, but in February 2019 there weren't actually any days which were warmer than 0°C. That gives February 2019 the honour of being 1 of only 15 months (out of 1,660) since 1880 to have no days above freezing. We talked about that more in Months Below Freezing.
Warm & Cold Months
As we saw earlier, February 2019 was the 5th coldest February since 1880.
And at -9.3°C colder than the 20th century average for February, it was one of the most abnormally cold months that we have had in a long time. Since 1880 there have only been 17 months which were that much colder than average, and the most recent was February 1979 at -11.3°C.
Recently September 2018 was also the 5th coldest September since 1880, but it was only -3.9°C colder than the 20th century average. That difference is because our temperatures are much more variable in the winter, and have a much larger potential range. We have talked about that seasonably variability a few times, but probably the best example was in How Normal is Average?
And in this chart the size of the bubbles shows how warm or cold each month of the year was, going back to 1880. A century ago the big, blue bubbles for cold months were quite common, but in recent years they have been fairly rare.
Since 2000 the most below-average months were March 2002 at -7°C colder than the 20th century average for March, and November 2006 & December 2009 both at -6°C below. And now we have February 2019 at -9.3°C.
The Horserace
In the middle of January we had looked at how mild the winter of 2018-2019 had been, in
2018-2019 Mid-Winter Review. At the time the cumulative temperatures had 2018-2019 up with some of our warmest recent winters, like 2015-2016 and 2011-2012.
That all changed with February though.
The cold, cold temperatures pushed us way down to the bottom rung of recent years. However, we are still (so far) warmer than the 20th Century average, and warmer than winters like 2013-2014 and 2010-2011.
The Neighbours
And this cold February wasn't isolated to Edmonton.
It was Calgary's 4th coldest since the 1880s.
In Winnipeg February 2019 was also cold, but it only ranked in 20th-coldest spot. And it was actually slightly less cold than the even colder deepfreeze that they had had during the last 2 weeks of January.
At the Edmonton International February's average temperature of -22.5°C made it the 2nd coldest February on record, after 1979 (although the records only go back to 1961). But February 2019's average Low of -28.8°C (-28.8°C!) was actually colder than 1979's -26.9°C.
We don't normally talk about the temperatures at the International Airport, but this month is kind of amazing:
- 24 Lows of -20°C or colder (in a month with only 28 days).
- 20 Lows hit -25°C.
- 14 Lows (2 weeks) hit -30°C.
- 7 Lows (1 week) hit -35°C.
- 1 Low below -40°C, on February 5th at -41.2°C.
No February in recent history has come close to that.
For February on average the Lows at the International were 4.4°C colder than Blatchford. But on February 5th the International was 10°C colder, with Blatchford at -29.5°C and the International at -39.5°C. And there were 8 other days where the International was 7°C or more below Blatchford.
Snow
Snow seems pretty boring compared to the temperatures, but the International did get 22cm of snow in February. That's more than the 16cm we had last year, and more than the average of 13cm.
Snowdepth
And because of the complete lack of melting during February, the snowdepth at the International has just climbed and climbed. Right now it's at 37cm, which is right at the top of the range for this time of year. The average is down around 23cm.
Normally the snow starts to melt pretty quickly right around the 1st or 2nd week of March, which we had looked at in The Big Melt. That didn't happen last winter though, and a very cold March and April delayed things by almost a month until the middle of April.
March Temperatures
After February I'm sure that almost everyone is looking forward to an end to this long deepfreeze. Unfortunately though, March is not a month that you want to put too much faith in.
March almost certainly is not going to be summer, and sometimes it's barely spring. March 2017 and 2018 both started with -20°C days, and in 2018 we hit -20°C on March 31st, which was ridiculous.
But March usually does have a lot of days above 0°C, which would be a nice change from the past month. The recent average is 20 days with Highs above freezing, although that's ranged from 2002 with 8 and 2011 with 11, up to 2010 and 2016 with 29.
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