Hey there, time traveller!
This article was published 13/2/2014 (811 days ago), so information in it may no longer be current.
The height of the snowpack in Winnipeg is twice the average for this time of year -- but don't go building an ark just yet.
Environment Canada says the moisture content of the snow on the ground in Winnipeg is relatively low, which means the sizable snowdrifts seen in and around the city this winter will not necessarily translate into prodigious puddles this spring.
"Just because there's a lot of snow on the ground, doesn't mean it's going to melt into a lot of water," said Natalie Hasell, an Environment Canada warning-preparedness meteorologist based in Winnipeg.
As of Feb. 11, the most recent date a snowpack-depth measurement is available, there were 40 centimetres of snow on the ground in Winnipeg, she said.
That's down from a season-high snow depth of 45 cm, a figure reached on Jan. 26. Since then, the snowpack has lost a little loft to wind, compaction and sublimation. The latter involves the disappearance of snow on sunny days, when frozen water is converted directly into water vapour.
The average height of the snowpack in Winnipeg at this time of year is 20 cm, which explains why some homeowners are running out of room to shovel the accumulation on their properties.
Another 10 to 14 cm fell on the city on Wednesday night and Thursday morning, but it's too soon to determine how much that has added to the snowpack, Hasell said.
Snow depth and the moisture content of the snow are only two of the factors flood forecasters use to predict the severity of spring flooding. The moisture content of the soil is also important, as dry ground can absorb more spring snowmelt, as is the volume of water in rivers and streams, because low volumes during the winter translate into a greater capacity to carry spring runoff.
The weather over the next few months is also important, as a late winter with a slow thaw is preferable to a fast, early melt. More snow adds to the flood risk, as well.
Snow, soil and waterway conditions across the entire Red River drainage basin also must be taken into account. For example, the high snowpack in and around Winnipeg is not indicative of snow depths elsewhere in the drainage basin.
South of the Canada-U.S. border, the U.S. National Weather Service reported low to average snow depth in the Red River Valley in January.
Regions of western Manitoba that drain into the Assiniboine River are also light on snow, according to anecdotal reports compiled by the Snowmobilers of Manitoba.
"We just recently opened trails near Virden and Russell. They just didn't have the snow," said Alan Butler, Snoman's president. "We don't have the snow we had last year, for example."
Manitoba is expected to issue its first flood outlook of the year later this month.