A ‘crucial’ time for avalanches | AspenTimes.com

A ‘crucial’ time for avalanches

Scott CondonAspen, CO Colorado

ASPEN Avalanche forecasters warn that conditions are precarious on backcountry slopes right now and timing of travel is “crucial.”Both the Aspen-based Roaring Fork Avalanche Center and the Colorado Avalanche Information Center warned in their reports Tuesday of two major developments – deep slab instability and wet, loose activity.The activity is common as temperatures climb to the levels they have reached this week, said John Snook, a forecaster with the Colorado Avalanche Information Center.The sun and unseasonably warm temperatures melt the top layer of snow on southerly aspects, Snook said. The water penetrates the snowpack and lubricates the different layers of snow, triggering wet, loose avalanches, he said.”Lots of wet loose activity has been observed on east-southeast aspects, including wet, loose, natural activity near Aspen Highlands on east-southeast aspects a little below treeline,” the state information center’s website reported Tuesday.High temperatures are in the forecast again today, so more activity is expected.”When you start to see roller balls or sluffs coming out of rock outcroppings, then it is time to leave these areas, even if it is still morning,” the website advised.The website for the Roaring Fork Avalanche Center sounded a similar warning.”Natural wet activity will be possible and human triggered slides will be probable on east-south-west slopes at and below treeline as the day progresses,” the Aspen organization said. “We are at the point of the season when picking your timing on specific aspects is becoming crucial.” Snook said the warmer temperatures typically stabilize the snowpack that doesn’t have a southerly aspect. The snowpack in northerly aspects “still think it’s winter” despite the warm, sunny days, he said.But the tricky thing is pockets of instability still exist, often in shady areas. The weight of a backcountry traveler on those isolated weak spots is “enough to trigger a large, deep slab avalanche,” the Colorado Avalanche Information Center’s website said.The Roaring Fork Avalanche Center warned people to be “especially cautious” on northwest-northeast slopes steeper than 30 degrees at and above treeline.” The warm temperatures have affected the snowpack there less, so slides can be easily triggered.Daily updates and more details are available at http://www.rfavalanche.org and at avalanche.state.co.us/.Scott Condon’s e-mail address is scondon@aspentimes.com.