Monday, March 10, 2008

Milder weather.. but when will the snow go?

Looks like a couple of milder days coming up, with near to slightly above freezing temperatures forecast through Wednesday. (Not sure about the +2 for today.. southerly wind out of an Arctic ridge.. but we should see near freezing anyways) This, along with that strengthening March sun, should help melt some of that 20-30 cm snowpack across the Red River valley. But it's going to take more than a couple of mild days to get rid of all this snow.. so the question is.. when can we expect this snowcover to go completely in the Winnipeg area? If we get into a mild pattern, the snow can go pretty quickly this time of year, sometimes within a few days. But this year may be a little slower due to an expected pattern of below normal temperatures the rest of the month.

For reference, here's a list of average dates when Winnipeg lost its snow cover over the last few years (+/- a couple of days depending on your location)

2007.. March 28 (30 cm snowpack on March 24th)
2006.. April 4
2005.. April 4
2004.. April 5
2003.. March 22
2002.. March 30
2001.. April 3
2000.. Feb 22 (+16.5C by March 6)

Based on this, climatology would suggest our snowcover should be gone the first week of April or so this year, barring any large snowstorms before then (let's hope not!) Take the poll (right) to vote on when you think we'll lose our snowcover this year.


  1. While Winnipeg struggles to get the freezing mark today thanks to a southerly flow over the Red River snowpack, a downslope flow has allowed temperatures to climb up to +7C in Portage, and +10C in McCreary! It's even well above freezing in the forested areas east and north of here including +5C in Pinawa, +7C in Grand Rapids, and +6C in Flin Flon. Darn that snowpack!

  2. Things always turn out worse than expected this year, so I vote on April 15 as the day the snow is gone. I think that's the long term average in any case

  3. Lots of +3 to +5C temperatures across the city today, with the airport a little cooler at +2C. One station, River Park South in Winnipeg, checking in with an unlikely +10c (poor siting likely).. although it sure feels that warm with all that sunshine. Lots of melting going on with deep pools of water on city streets due to locally clogged sewer drains. My snowcover dropped 5 cm today alone. Nice to see and remember to top up that washer fluid!

  4. According to Manitoba Agriculture (Station in Steinbach) the temperature here reached almost +6. I guess if you were to round it it would be +6.

    Some significant snow melt has happened here and bare ground is slowly emerging. Yesterday roads that were covered in snow were revealed and river started flowing down streets.

  5. The snow is about 60% melted in my area of Winnipeg, bare ground is visible in may spots.

    Though the snow is melting, the same can't be said for the Red River ice. Remember last years ice jam at Selkirk? That Winter the ice thickness was 20 inches. This Winter, the Red River ice thickness is on average around 40 inches or more. If breakup doesn't go smoothly and problems occur, it looks like another ice jam is possible on the Red River.

  6. Jon..

    Good point. It'll be interesting to see how the break up goes this year. I understand they have a couple of cutters that will be trying to score the ice to make break up easier. One thing you need for a bad ice jam is to have a fast streamflow which we may not get this year due to the low amount of snow and gradual melt. Last year, we had twice as much snowcover and a rapid melt, plus a fairly heavy rain event at the end of March that increased flows on the Red. Barring any major precipitation events, the drier and colder conditions this year may save Selkirk from a repeat performance, even with the thicker ice. But they'll be watching nervously I'm sure.. ice jams are notoriously difficult to predict.

  7. Strangely, the airport is still reporting a snow depth of 27 cm as of March 17... this after an apparent peak of 33 cm on March 12. This is the same depth reported at the beginning of March last year. Clearly snow depths in the city were greater last year... are they measuring from the middle of a snow drift or what?

    It is also strange that YWG has only lost 6 cm with all the above freezing temps including a couple of nites above zero (even at YWG proper).

    Hallock, Grand Forks, and Fargo have 'soared' to 5-6 C today. It looks like the generalized snow cover in open country is pretty much gone down there. Areas west of Portage also appear to be snow free.

  8. Daniel..

    That snowdepth at the airport is being measured using a sonic snow sensor.. an automatic device that uses soundwaves to estimate snowdepth. Not that reliable, and will only measure in a spot directly below the sensor. So if there is heavy drifting, the values can be quite variable and non-representative of the general area. Unfortunately snow measurements are no longer done at the airport (a bone of contention for many of us). Our human climate observers usually give better readings because they can estimate the snowdepth in several locations and come up with an average.

    FWIW.. my snowdepth is down to 11 cm here in Charleswood as of March 19th, but that is quite variable due to the heavy drifting this year. I have bare grass in some spots, and 30 cm or more in drifted areas. Slowly but surely though it's going down.. but it looks like a slower melt this year than last year when my 30 cm snowpack virtually disappeared in 4 days last March.