High-country snowpack should be even fatter after a couple of snow-producing storms move through Southwest Colorado this week. The coldest storm is expected Sunday.
Six to 10 inches of snow fell from Wednesday night through Thursday above 8,500 feet in elevation in the San Juan Mountains.
“This one is coming from southern California and will be warmer. In the lower elevations, you’re likely to see rain. You may see a dusting in Cortez and Durango and maybe an inch in Pagosa Springs,” said Matthew Aleksa, a meteorologist with the National Weather Service in Grand Junction.
Telluride Ski Area on Thursday reported 2 inches of new snow, with snow expected to continue through the day before the storm moves out Thursday night.
Rain prevailed in most lower elevations Wednesday night and Thursday morning, although Pagosa Springs did receive 3 inches of snow by Thursday morning.
On Thursday morning, Wolf Creek Ski Area reported 6 inches of new snow in the previous 24 hours and expected more snow later Thursday. Silverton reported 2 inches of new snow Thursday morning.
Partly cloudy skies are expected in Southwest Colorado Friday and Saturday. A new storm is expected about midnight Saturday, said Mike Charnick, an NWS meteorologist in Grand Junction.
Sunday’s stormEarly Sunday morning, perhaps even late Saturday night, Aleksa said a colder storm system from the Pacific Northwest might leave snow along the U.S. Highway 160 corridor.
“There may be accumulations in lower elevations. It’s moving quickly, so it depends on when cold air cover moves in, but this looks like it has the potential to leave lower valley accumulations,” Aleksa said.
Charnick said perhaps an inch of snow could fall from the storm in Cortez and Durango, although the precipitation could also come as rain.
The storm is expected to clear out of the region Sunday night or early Monday morning, and the next chance of precipitation in Southwest Colorado will be the following weekend.
The Sunday system should move out of the region on Monday, with perhaps stray snow squalls still providing some snow early Monday in the high country, Charnick said.
According to the weather service, storm patterns could continue throughout December because a ridge over much of the western U.S. has broken down, and that is allowing storms that were skirting north of the Four Corners to target the area.
Backcountry slidesSnowshoers had a close call Nov. 30 after being caught in an avalanche on Red Mountain Pass.
“They triggered a slide that ran down on top of them,” said Ethan Greene, director of the Colorado Avalanche Information Center. “And it took them for a ride.”
A snowstorm that started before Thanksgiving brought much-needed snow to Southwest Colorado. Before the storm, snowpack in the basin was around 60% of historic averages. As of Wednesday, however, snowpack in the San Juan River Basin was at more than 106% of the 30-year average for this time of year. The welcome snowfall, unfortunately, also set up the “perfect recipe for avalanches,” Greene said.
In the San Juan Mountains through early December, 21 naturally caused avalanches have been reported to the CAIC (and that’s just reported slides), and an additional six avalanches have been triggered by skiers, snowshoers and snowmobilers.
Greene said snow in October set up a weak base layer of snowpack, which was made even more fragile during a dry November. So when the Thanksgiving storm dropped a couple of feet of snow on top of that unstable layer, it wasn’t a surprise when avalanche activity picked up.
“That’s why we issued an avalanche warning,” Greene said.
Several close calls were recorded the past few days.
Besides the slide on the east side of Red Mountain Pass, an avalanche occurred that day near Wolf Creek Pass. It was caused by snowmobilers in the Lane Creek drainage. The crown, CAIC reported, was 1 to 3 feet deep and about 75 to 100 feet wide.
“It didn’t run very far, but it was a high-consequence terrain trap,” according to the observation report.
Greene said travelers in the backcountry face the risk of a “remote-triggered” avalanche – when a traveler’s movement starts to fracture the snow, starting an avalanche process above or below the traveler.
And when it happens to start above you, you’re in danger, like in the case of the snowshoers, Greene said.
“You need to be conscious of the terrain you’re connected to,” he said.
Snowpack starts to strengthen after a storm passes.
“We’re not seeing avalanches happen every time people touch the snow like we did right after the storm, but we still have a weak layer and tricky conditions,” Greene said.