Snowpack at 'very low' levels

Mountain snowpack in Northwest Montana and the rest of the state is now considered “very low,” and it’s not likely to recover.

The Natural Resources Conservation Service reports that by the end of February, the mountain snowpack west of the Continental Divide was 65 percent of average. East of the divide the snowpack was 71 percent of average.

“We’re obviously going to have low stream flows this summer. With that kind of snowpack, there’s really no way to recover from it now,” said Ray Nickless, hydrologist with the National Weather Service in Missoula.

“We’re pretty much running into the low end of our snow accumulation period,” said Roy Kaiser, a water supply specialist with the Natural Resources Conservation Service in Bozeman.

West of the divide, 82 percent of the typical snowfall period has passed, Kaiser said. “So we have less than 20 percent of our snowfall period remaining. Then it will come up to whatever we get for rain.”

The nature of spring runoff will be important for stream flows.

“It will be totally dependent on how the snow comes off with temperatures and supplemental rains,” Kaiser said, adding that a slow melt would help maintain stream flows.

In Montana’s combined river basins that feed the Columbia River, the mountain snowpack is 65 percent of average.

Snowpack above the Kootenai Basin is at 66 percent of average and the snowpack above the Flathead Basin is at 71 percent.

Stream-flow forecasts, which assume there will be near-normal spring precipitation, are 63 percent of average for the Kootenai and 72 percent for the Flathead basins.

“It could be even worse,” Nickless said, noting that the Bitterroot snowpack is 52 percent of average and the stream-flow forecast is  51 percent.

The National Weather Service was predicting this would be a below-average winter for Montana snowpack because of an El Nino weather pattern that has caused Pacific weather systems to cross the country south of Montana.

The last El Nino winter was in 2004 and 2005, and “there was a very low snowpack that year,” Nickless said.

The Flathead basin was at 60 percent of average by March of that year and the Kootenai was at 58 percent

“So I guess the good news is that we’ve seen this before,” Nickless said. “The bad news is that if we don’t get much moisture this spring and we have a hot summer, we could be looking at a lot of problems across Western Montana.”

February mountain precipitation was well below average for the fourth consecutive month. The mountains west of the Divide had just over a third of the usual February snowfall while east of the Divide reported about half its normal amount.

Snow has been scant in the Flathead Valley as well as in the mountains.

The total snowfall this season in the valley is 36.5 inches, compared to the normal 52.2 inches. 

Reporter Jim Mann may be reached at 758-4407 or by e-mail at jmann@dailyinterlake.com