Friday, 1 March 2013

Time to Reflect on Winter 2012/2013

Click to enlarge
     Despite finishing just over a half degree colder than normal, winter 2012/2013 (or the Dec 1 to Feb 28 period in meteorology land) was tied for 48th warmest. This means out of the 140 winters of data in Winnipeg, 65% of winters in our climate record were colder than this winter. This just goes to show how much our winters have actually been warming in the last few decades. Although it may have felt like a cold winter after last year's non-winter, it was nothing compared to what used to be normal over a half century ago.

     All this to say that temperatures were relatively not too bad. There were only two ''real cold to frigid'' periods; around Christmas and then from mid January to the first couple days of February. In total, there were 9 days with wind chill values below -40.0 this winter which is less than the 1971-2000 normal of 14 days. The lowest wind chill value was -45.3 on February 1. There were also 8 days with a minimum temperature below -30.0°C, also less than the 1971-2000 normal of 13 days. Of note, a low of -33.1°C on January 20 was the first -30°C reading since February 2011. That broke a 694 day streak without hitting -30°C, the second longest streak of its kind since 1872. The longest was a 714 day streak from Feb 15, 1930 to Jan 29, 1932.

     However, the biggest stories of the winter were easily the snowfall and the blizzards. Light snowfalls and clipper systems dominated December, January and half of February dumping light to moderate but frequent snowfalls. A total of 80.8 cm makes it the snowiest winter since the winter of 2005/2006 when 84.2 cm fell, and nearly double last winter's total of 44.2 cm. However, this is not even close to our snowiest winter of 147.3 cm in the winter of 1909/1910.

     Three major snowstorms and/or blizzards stood out among the rest, all in January and February. On the night of January 11/12, widespread blizzard conditions impacted the Red River Valley. Heavy snowfall combined with 50 to 60 km/h winds and gusts over 70 km/h to create whiteout conditions, especially on highways. 10-15 cm fell over Winnipeg while 15-25 cm fell to the southeast of the city including in Steinbach. The deep drifts that were created made it especially difficult to get around.

     Just a week later, severe blowing snow impacted the RRV on January 19. Although it was not bad enough to be a blizzard, whiteout conditions were seen at times. 5-10 cm of snowfall had fallen over Winnipeg with the storm which combined with 40 km/h winds and gusts over 50 km/h.

     The blizzard of February 18 (Louis Riel Day) was the most tragic. 4-7 cm fell over Winnipeg along with 10-15 cm south and east of the city. In the RRV, sustained winds between 50 and 70 km/h and gusts as high as 80 km/h whipped up the new snow to create whiteout conditions. Major highways were closed, several crashes were reported and even a few power outages were seen. One man died near Landmark after being stranded in the ditch in whiteout conditions.

     Since October, 123.8 cm of snow has fallen on Winnipeg, already more than what we would normally get in an entire season (October to May normal is approximately 117 cm). With March and April left, it will be interesting to see how much snow we'll add to that total. As for flooding, the government only expects a minor to moderate flood risk. I agree with this prediction at this time mainly due to the fact that the ground is relatively dry after two dry years. However, surprises such as ice jams do occur and thus, we will have to wait and see.

     Rainfall in December was also something this winter that is worth noting. 3 rainfall events during the first few days of December dumped 3.0 mm on Winnipeg. This made December 2012 the 9th rainiest December on record.

     As for the forecast, a major storm will be scraping southern Manitoba on Sunday/Monday to the southwest. Models have been flip flopping with what will happen, therefore it's hard to say what will happen at this point. I will provide updates this weekend. Meanwhile, it's nice knowing that things will only get warmer now that winter is slowly easing its grip!


  1. Just FYI, it was been a lot warmer in southern Alberta in February (compared to normal).

    Calgary had an average mean of -1.1°C in February which makes Feb 2013 tied for 7th warmest on record for the city.

  2. Monday's Alberta clipper system is still a very tough call with this morning's models.

    GEM only gives southwestern Manitoba a decent coating of snow, especially along the Saskatchewan border with easily over 10 cm. Meanwhile, it gives little to nothing for the Winnipeg area.
    GFS misses Manitoba altogether to the southwest, with snow moving into North Dakota instead.
    NAM brings it right through southern Manitoba with a bullseye close to the Saskatchewan border of over 20 cm. It gives Winnipeg over 10 cm as well but we'd be only right on the edge of this heavier snow.
    ECMWF gives Winnipeg 10-15 cm.

    As you can see there's a wide variety of solutions out there right now. My gut feeling at the moment is that the bulk of the snow will miss Winnipeg to the west, but I do think we'll get at least some flurries with it. Really hoping things come into more agreement tomorrow because this is a fairly potent system we're talking about here. Whatever happens, there's a good chance for blizzard conditions in southern Alberta and parts of southern Saskatchewan tomorrow and Monday.

  3. There will be some light snow here and there for the next couple hours in the city. I don't expect much accumulation at all.

  4. Consensus has really grown that a major snowstorm is set to hit southern Manitoba tomorrow. Southwestern Manitoba indeed does look to receive the heaviest snow with 15-25 cm possible with even as much as 30 cm closer to the US and Saskatchewan borders. Right now it looks like Winnipeg could get anywhere between 5 and 15 cm. I will have a new post up this afternoon because I have some things to finish this morning first.

  5. GEM Regional and NAM now give Winnipeg near 20 cm in their morning update..

  6. Both the GEM Global and GFS have now switched to a more easterly solution in their late morning updates giving 10-15 cm; a jump from the 5-10 they said early this morning. Consensus keeps growing more and more on a heavier snowfall for Winnipeg.

  7. Not too alarm anyone, but a weaker clipper system is already looking possible late week. It doesn't look overly significant right now so I wouldn't cancel any plans or anything just yet. I just wanted to get that out.

    As for tomorrow, well, I'll have a post on it sometime between 5 and 7 pm.

    Snowfall warnings have been extended all the way to the Perimeter, but do not include Winnipeg at this time. I'd have to agree with EC's decision to do that as it is still not 100% certain how much Winnipeg will likely get. In addition, we may just end up on the fringe of warning criteria.

  8. Computer issues are preventing me from posting my forecast. I hope to have it posted very soon