2019-2020 Winter-in-Review - Part 2 - Snow

Today we are going to take a look back at Edmonton's snow during the winter of 2019-2020.

If you are interested in the temperatures from the winter we took a detailed look at them: 2019-2020 Winter-in-Review - Temperatures.


Caveat: Winter is not (necessarily) over yet

Sometimes, Edmonton gets snow in May (and even very occasionally in June). In this chart every bubble represents a May or June snowfall at either Blatchford or the International. Late snow doesn't happen every year, but it actually averages out to about 1/2 the time.

In recent years 2016, 2017 & 2018 had snowless late-springs, but then in May 2019 the International recorded 4 snow days. And sometimes we're talking a lot more than just a few flakes: those big bubbles are for 11cm of May 6th 2015, 16.8cm on May 4th 2010, 17 cm on both May 5th & 6th 2003, and so on.

So fingers crossed, but who knows?

The reason that we will do the winter snow wrap-up now is because of this:


Snowdepth

The snow at the International finally melted on April 22nd. Environment Canada doesn't report 0cm of snow anymore, but the final snowdepth recordings were 1cm on April 15th at Blatchford, and 2cm on April 21st at the International.

The little bargraph at the bottom of this chart shows years which had snow on April 22nd, at it is a short list.

Looking back over the winter as a whole:

• a storm on November 10th pushed the International up to 19cm, and Blatchford up to 10cm.
• Blatchford melted back down to 0cm for about a week, while the snow at the International hung around. 
• From the beginning of the December the snowdepth at both stations climbed fairly steadily.
• For Blatchford the snowdepth peaked on February 18th with 32cm, but at the International the peak wasn't until March 8th with 41cm.
• Snowdepth had a few dips in March, but the big melt didn't really start until April 6th at Blatchford and April 7th at the International.

Snowdepth Each Year

Here we have the snowdepth throughout the year compared to other recent years. Only about 8 winters fit onscreen at a time, but the data going back to 1955 is all here if you scroll down a bit. (Blatchford data was missing from 2012-2015, if you're wondering)

This winter's peak of 41cm at the International was below 2018-2019's peak of 45cm, but was higher than the four winters from 2014-2015 through 2017-2018. The last time that we saw a peak above 50cm was 1996-1997 with 53cm, and 1973-1974 was a really big year reaching 84cm in late March.

It is fairly common for the snow at both stations to melt by about the beginning of April, but there are some winters - 2019-2020, 2017-2018, 2012-2013, etc - which drag things out for a few extra weeks.

The International's final day with snow was April 21st, and here we have the only recorded years with snow the day after that on April 22nd. And since records began in 1955 there were only 7 years with snow that late:

• 2008, 1985 & 1972 don't really count because they were all on their second round of snow.
• 2013 lasted until April 25th
• 1974 lasted until to April 22nd
• 1967 lasted until April 24th
• 1965 lasted until April 23rd

So the melt of 2019-2020 was almost as late as it gets.

For some context this chart has a comparison of the snowdepth through they year for various Canadian cities. It's currently set for Edmonton (Blatchford data only), Calgary & Montréal, but Vancouver, Winnipeg, Toronto, Ottawa & St. John's are in there too.

All the other cities had melted long before Edmonton...except for St. John's where the snowdepth peaked at 125cm(!) in January, and lasted until April 14th.


Lasting Snow

Back to Edmonton, the International finished off the winter of 2019-2020 with 169 days in-a-row with snow on the ground, from November 5th to April 21st. In 2017-2018 the International went 172 days, with an earlier start on October 31st, and the final melt on April 20th.

For 2019-2020 Blatchford went 141 days from November 27th to April 15th.

And here we have a look at other cities again:

• For Edmonton (Blatchford) and Winnipeg it's fairly typical to go 120 or more days with snow on the ground.
• Calgary often only goes about 50 days in-a-row with snow, but in 2019-2020 they went 99.
• Montreal goes about 75 days in-a-row, which Ottawa is closer to 100.
• And of course Vancouver rarely has snow on the ground for more than 10 days in-a-row.

First & Last Snow

It's always possible that we will get more snow, but right now it looks like the final snowfall of 2019-2020 at the International was April 15th, which is earlier than the recent average of April 24th.

And back in the fall the first snow was October 7th, which is about average over the long run, but is late compared to some recent years: 2018 was September 12th, 2017 was September 19th, 2016 was actually August 27th, and 2014 was September 8th.

So from first snowfall to final snowfall was 191 days, or a bit over 6 months.


Monthly Snow

Broken down by months this is how things went:

• October through January were all in the normal range.
• February & March were a little high, but nothing extreme.
• April's 5.5cm was the most below-average month.

And here we have Calgary & Montréal for comparison again, with data for all of the other cities accessible as well:

• Calgary has 114cm of snow in September through November, which was its snowiest early-winter since 1945. Then December and February through April were all fairly average. January was very low with only 3.9cm.
• Montréal's February was high with 67cm, and its March & April were both below 10cm and very low.
• Winnipeg had its snowiest October since 1919. St. John's had a massive January, and Vancouver's was above their average too. Toronto's February was above average, 

Total Snow

The International's total snow for the winter of 2019-2020 (so far) ends up at 125.6cm, which is basically right on our average.

And this messy chart has the snow totals for all of the cities for 2019-2020:

• Halifax was way up at 412cm
• Calgary, Montréal & Ottawa were all around 190-200cm.
• Toronto 139cm was above Edmonton's 125cm and Winnipeg's 102cm.
• And Vancouver was way up at 45cm, (their average is 35cm)

Large Storms

During the winter of 2019-2020 the International only recorded 2 days with 10cm of snow: November 9th with 11.4cm, and January 22nd with 10.5cm. On average we get one or two 10cm snowdays each year, so that was fairly typical. We only had 4 5cm snowdays, and that was a bit below the average of 7 each winter.

And finally, one more messy chart which shows the 20cm snowdays this winter for the various cities:

• Calgary had 24.6cm on September 29th.
• Winnipeg had 21cm on October 10th.
• Montréal had 27.4cm on February 7th.
• And St. John's had 23cm on December 24th, 30.2cm on January 5th, and then approximately 76cm on January 17th (the official data is missing for that day).

Summary

Generally the snow for the winter of 2019-2020 in Edmonton was fairly average...with one notable exception:

• the one unusual thing was that the final melt was very late. It was similar to 2018 & 2013, but was almost a month later that 2016, 2015, 2014...
• The total snow of 125.6cm was basically right on our yearly average.
• The snowfall for all of the months was fairly typical: February's 23.6cm was a little high, and April's 5.5 cm was quite low. 
• The first snow on October 7th was average, and the final snow (so far) on April 15th was a bit earlier.
• We had two 10cm snowdays which is the average for each winter, but we also typically get about seven 5cm snowdays and 2019-2020 only had four.
• We couldn't possible cover all of the the other Canadian cities in detail, but Calgary & Winnipeg both had very snowy autumns, and St. John's & Vancouver (of all places) had snowy January's.