Snow flocks trees on the Sasquatch Ski Trail on the south side of Mount St. Helens in early January. (Allen Thomas/The Columbian)Photo Gallery
There is a lot of snow in the mountains of Southwest Washington, but not for the reasons you might think.
As of Sunday, the Lower Columbia Basin, which includes the Lower Columbia River, Lewis River Basin, Cowlitz River Basin, and Mount Hood, was at 124 percent of normal snow water equivalent — the largest in the entire state.
But officials say that accumulation isn’t connected to the big snowstorms that hammered the Portland and Vancouver metro area a couple of weeks ago.
In fact, the snowpack’s performance against the norm shrank 9 percent between Jan. 1 and the start of this week.
It’s not that snow in the mountains melted, either. Around the week of Jan. 14, when the temperature dropped and the sky was dumping snow downtown, conditions were pretty dry in the high elevations.
“That disproportionate amount of snow you got in the cities makes you think we’re going to get dumped on” across the landscape, said Scott Pattee, a water supply specialist with the U.S. Department of Agriculture’s Natural Resources Conservation Service. “But the thing was, we weren’t receiving a normal daily amount of snowfall in the mountains even though the valleys were getting dumped on.”
Pattee also said it typically snows a little bit every day in the mountains, thus deepening the snowpack at a steady pace through the winter. But no snow fell during that cold week, and it eroded the surplus.
Still, the region is in pretty good shape. Of the entire Lower Columbia Basin, June Lake, on the southern flank of Mount St. Helens, has the most snow, at 146 percent of normal.
Statewide, the snowpack is 102 percent of normal, with some areas below average. The Upper Yakima Basin is at only 79 percent of normal.
Currently, the snowpack at elevations above 4,500 feet from Mount Rainier to Mount Hood is slightly below normal levels, Pattee said. But that’s due in large part to a lack of early-season snow that typically hits those areas.
The winter storm track moved over Oregon and delivered heavy early-season storms, leaving Washington comparatively drier, Pattee said.
Given that, some weather predictors believe La Niña is going out for the season.
“In a La Niña year, we’re normally the ones that get dumped on, and Oregon is dry,” Pattee said.
Morning Briefing Newsletter
Get a rundown of the latest local and regional news every Mon-Fri morning.
