The people who monitor snowpack in the mountains are seeing some eye-popping numbers in the Kootenays this year.
They say a monitoring station near Nelson is showing above-normal snowpack — and that was before all the snow we’ve received since New Year’s.
“On Jan. 1, the West Kootenay snowpack was 111 per cent of normal, which means it’s 11 per cent above normal,” says Jonathan Boyd, a hydrologist with B.C.’s River Forecast Centre, which monitors river levels and flooding in the spring. “So far, since then, we’ve seen a 10 to 15 per cent increase. Our station in Redfish Creek has gone from 110 per cent to tracking at 124 per cent.”
Boyd says the 18-year-old station is now tracking some of the highest numbers it’s ever recorded.
It’s not the only station to be registering high numbers. Overall the West Kootenay snowpack is 136 per cent of normal, says the Centre’s January report.
“Another station in the West Kootenay is Barnes Creek, it goes back to 1993,” says Boyd. “It has the second-highest ever snowpack recorded, just below 1997, which was a very high year. And that’s consistent for almost the whole southern Interior.”
Several storm systems have impacted B.C. over the past two to three weeks, with heavy precipitation falling across most regions.
Warm spell irrelevant
Even the warming the West Kootenay has seen in the last week — with rain falling on several days — will have little impact on the overall numbers.
“I think it primarily is related to lower-elevation snow,” says Boyd. “Although the temperatures in the valleys are warmer, where the real snow is— in the higher elevations— even if it does rain a day or two, or get to 3 or 4 degrees, the temperature of the snowpack alone just absorbs the rain and freezes it.
“It’s not until we get into the 14 to 18 degree-range that it really starts to rapidly melt in the higher elevations.”
Hitting record snowpack levels seems almost certain. While a lot of snow has fallen, there’s still plenty to come.
“At this time of year, we have about 60 per cent of the snow fall by this date,” says Boyd. “So we have about 40 per cent of the snow accumulation season to come, on average.”
Snow accumulation can be over by April, or even continue until late May in unusual years, Boyd notes.
Overall, the provincial average from all automated snow weather stations currently sits at 100 per cent of average, up from 89 per cent on Jan. 1, the Forecast Centre says. Most regions experienced a five to 30 per cent increase in the percentage of average values over the past two weeks.
Current percentage of average values range from a low of 59 per cent on Vancouver Island to a high of 136 per cent in the West Kootenay. Many regions, including the Upper Fraser – East, Upper Fraser – West, North Thompson, South Thompson and Okanagan, are beginning to nudge into high snow pack conditions (greater than 120 per cent).
In the western coastal areas of the province, snow pack remains below average.
Snowpack monitoring and river forecast allows emergency officials — and citizens — to prepare for the possibility of flooding in the spring.
“It’s about being prepared for the upcoming freshet,” Boyd adds. “We’re certainly trending up into the higher, well-above normal for the Kootenay. It’s always good to be prepared, that’s why we do the measurements early, so people aren’t learning about the flood risk in May.
“One of the ingredients [for flood risk] is a high snowpack, and we can guarantee as of this moment, the Kootenays is very high.”
Many factors can affect that risk, from the speed of the melt to rainfall during the freshet. But Boyd says whatever happens, it’s best to be prepared.
And we will get a better sense of the situation in early February, when the next comprehensive snowpack report comes out.