2016-2017 Winter in Review - Snow (so far)

Earlier this week we took a look back at the temperatures of the winter of 2016-2017, and today we're going to look at snowfall. Our snow isn't necessarily over yet, because we'll probably have a few more snowy days in April or May. But today we'll work with what we've got, so far.

This will be a quick run through of all of the snow charts that I've got, and most of them are based on data from the Environment Canada weather station at the International Airport. The Airport isn't necessarily a perfect representation of the city, but snow measurements at Blatchford in the past few years have not been good. If there is Blatchford data available though, I'll include it for comparison.

Snowdepth

We've looked at snowdepth quite a bit in the past few weeks, but here's a reminder of where we are in the first week of April.

We got lots of snow in early-October, but were below average for most of the winter, and then dropped very close to 0cm at the end of February. Early-March delivered quite a bit of new snow, but that quickly melted. On March 21st we dropped to "trace"amounts of snow of the ground, and on March 29th we hit 0cm.

Here is a comparison the snowdepth for each winter going back to 1995-1996. The last 3 winters have all had relatively little snow and early melts. But that follows a few years like 2010-2011, 2012-2013 and 2013-2014 which were all quite snowy.



Hitting 0cm on March 29th makes the winter of 2016-2017 the 8th-earliest melt at the International Airport, just behind 2014-2015, and about two weeks later than last year. But 2016-2017 is about a week or two earlier than a "typical" winter, and a month earlier than slow years like 2010-2011 and 2012-2013.

Snowy Days

This chart shows how many snowy days we typically get each month, and for 2016-2017 we bounced around the average, right in the range from the 25th-75th percentile.

This data is from the Airport, which actually did record tiny amounts of snow in August & September - 0.1cm on August 27th, and 0.4cm on September 4th. We've seen that the airport can get much colder than the city though, and on those days it stayed well above freezing in town.

This chart is originally from how often does Edmonton get snowstorms, and it shows how much snow we get during a typical snowfall - 1cm, 2cm, 5cm, etc.

For all of recorded history at Blatchford and the International, about 45% of the time a snowfall is less than 1cm, and about 65% of the time it's less than 2cm. Large snowfalls of 5cm happen about 15% of the time, and more than 10cm is less than 5% of the time.

In 2016-2017, our various snowdays lined-up pretty nicely with the longterm averages. This winter we didn't have any days with more than 10cm, but October 14 was very close with 9.5cm, and our 2nd-snowiest day was 7.6cm on March 4.

Snowy Months

Our snowiest month this year was March, with 27cm, which is not unusual. Our 2nd-snowiest was October though, and at 22cm it was well above the average. December was pretty close to average, and November, December and February were all on the low-side of things.

Cumulative Snow

When we add up all of those snowfalls over the course of the winter, this is where we end up.

For most of the winter 2016-2017 was hugging the 25th percentile, until moving up a bit closer to the average in March. So this was a low-snow year, but not a really low one

Our total average snowfall each winter is about 125cm, and as of the beginning of April we're sitting at 100cm.

Total Snow Each Winter

This is the recorded history of winter snowfall totals, which we first looked at here.

There's a lot of variation from year to year, but an average of about 125cm each winter has been fairly consistent, going back to the start of the 20th century.

In recent winters we've mostly bounced around between 100cm~150cm. Although there have been standouts like 2002-2003 with 225cm, and 2000-2001 at only 38cm. Last winter 2015-2016 was also very low at 53cm.

As of April 4th we're sitting at 100cm of snow for 2016-2017, but there are still two months left:

April & May

Finally for today, here is the same chart that we were just looking at, but this time it is only showing the snow totals for April & May. This is what we might want to expect from the next two months.

At the International Airport, since 1960, the only year that recorded 0cm of snow in April & May was 1998. There have been a few other low years though, and last year was quite low with 4.8cm. The flipside of that is a year like 2003, which recorded 70cm of snow in these two months.

More typically we get about 20cm of snow during April & May, and so far this April we're at 4.2cm (which is not shown on the chart). So everyone should have their 2nd-winter Hobbit-memes ready, because the snow is probably not done with us yet.