Western Boreal Forest
Winter still has a hold on much of the region, and it is showing few signs of letting go. Snow is still falling in good quantities, and temperatures are remaining low enough to prevent melting. Runoff should be normal overall, although it will likely be greater in southern areas.
Snow levels are average to slightly above average for most of the Yukon. Temperatures have been well below normal through much of February and March, and there has been very little precipitation. In most areas, spring conditions will likely be average. Migrants should start appearing towards the end of March, with swan migration peaking in the third week of April and duck migration peaking in early May.
In February, precipitation was slightly lower than normal in Yellowknife, and almost three times higher than normal in Norman Wells. In March, although these areas typically receive an average of 13.4 and 11.5 mm of precipitation within the month, repectively, Yellowknife has only received 3.6 mm, while Norman Wells has only received 1 mm as of March 21.
In northern Alberta, precipitation has been about average in High Level and Peace River.
Much of northern Saskatchewan will likely have normal runoff, although some areas (including Meadow Lake) are expecting more than usual. Some melting has started, but the real melt is not expected to get underway until April.
There is a lot of snow on the ground in northern Manitoba, where significant spring runoff and good habitat conditions are anticipated. Spring break-up will likely be normal, although it may be late considering that winter conditions still prevail and there have been few signs of melting as of yet.
The Saskatchewan River Delta has received above normal precipitation (over 120 per cent) between early September and late February. Manitoba Water Stewardship's second spring flood outlook (released February 24, 2011) indicated that: "With average conditions, the Saskatchewan River would be expected to see flood levels slightly higher than the 2005 flood at The Pas. With unfavorable weather conditions, general flooding could occur. Brief localized flooding is also possible due to snow-blocked or ice-filled streams, drains or ditches. If unfavorable weather conditions develop, flood levels higher than 1974 are expected on the Saskatchewan River at The Pas." From an ecological perspective, high-water events are critical for: recharging wetlands in the delta; depositing nutrient-rich water and deltaic soils; and contributing to the high fertility of delta wetlands.
March precipitation has been favourable, with close to average snow amounts, but temperatures have been much colder than usual. This could increase the flood potential for April and early May, if prolonged cold temperatures are followed by a rapid spring melt.
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