JACKSON HOLE, WYO – A decent dose of snow slammed the valley Sunday, with the storm wringing itself out later today to begin a dry spell in Jackson this week.
Powder hounds will no doubt be calling in with a sudden case of ‘backcountry flu’ but take note before you grab your boards and head for the high country.
Bridger-Teton Avalanche Center has spiked the avalanche hazard forecast to HIGH in the Teton and Greys River districts for the first time this season. Togwotee is rated as CONSIDERABLE. On a scale of 5, a ‘high’ rating is 4 and it means travel in avalanche terrain is not recommended.
Up to 17 inches of new snow has fallen in the mountains since early yesterday morning. That, and the winds, have avalanche forecaster Bob Comey concerned. Especially the wind.
“The forecast is for very high sustained winds—all the way to the valley floor level, and we haven’t quite seen that so far this season,” Comey said. “We are already getting gusts 50-60mph on ridge tops. Gusts from 25-35 in the valley will be possible for most of the day. That’s putting a pretty good load on the snowpack.”
Wind-loaded slopes will create dangerous conditions today. Natural avalanche activity is likely on a variety of aspects at all elevations. Large avalanches are likely and very large avalanches are possible, according to the Bridger-Teton Avalanche Center.
What’s worrisome to Comey is the layering of the snowpack.
The snowpack has really poor structure, especially at lower elevations,” Comey said. “We have these weak layers and, with heavy snowfall—maybe an inch or more an hour—or with wind greatly multiply that loading by drifting snow, you put more weight on these weak layers. During a snowstorm like this we could see some sizable natural avalanche activity.”
The good news is, more avalanche fatalities occur when the forecast is lower—at, say, considerable or even moderate. Reason being is two-fold. When the avalanche hazard is high or extreme, most people are prevented from even getting out to the mountains because of the weather. Those that do are usually very conservative and more mindful of the conditions.
When things settle down a bit, the ‘human factor’ takes over, Comey said, when skiers and riders become bolder in search of pristine powder stashes.