Good morning, this is Travis Craft with the West Central Montana Avalanche Center’s early season update for November 10, 2017.

Mountain temperatures range from 22 F to 32 F in the region. Winds are 9 mph with gusts of 12 mph out of the South in the Bitterroot. Point Six, in the northern part of the advisory area, winds are reading 8 mph with gusts of 11 mph out of the West. The region has picked up 1 to 3 new inches of snow in the last 24 hours. This storm is exiting the area and a new system will arrive over the weekend bringing snow above 4000 ft. The backcountry weather forecast is now live on our weather page here is the link.

Logan and I toured near Lost Trail Pass yesterday. We found wind scoured slopes and wind slabs on leeward terrain. Ryan went to St Mary’s in the Central Bitterroot on Nov 06. He found lots of snow viable for transport. We all found weak layers in our snow pits that should be accounted for by digging a pit to see how reactive they are before committing to any steep slopes.

The primary avalanche problem is wind slabs. These slabs are reactive to human triggers. Leeward terrain will have wind slabs that are likely to be reactive to human triggers. Logan I were able to get an interface of a wind slab and old snow to propagate in an ECT.

The second avalanche problem is storm slabs. New snow will need time to bond to old snow surfaces.

The third avalanche problem is persistent slabs. There are facets in our snow pack it is worth digging in the snow and seeing how reactive these layers are before committing to any steep terrain.

Across western Montana, there are backcountry locations that experienced wildfires during the 2017 season. Temporary emergency trail closures for the Lolo Peak (from the Mormon Ridge trailhead), Mill Creek and the Lantern Ridge trails. These burned areas, while sometimes opening up new skiable terrain, may also present hazards for backcountry skiers. Trees burned may have weakened or completely burned root systems. They could fall without warning – even in no wind conditions. Trees and other vegetation that may have anchored snow on steeper slopes in past years may now be completely burned. Downed trees from a fire can create unseen hazards on shallow snowpacks.

As always, be observant of conditions – not just the snowpack, but also what is above the snow when moving through a recently burned area, especially in strong and gusty winds.

In past years there have been many early season close calls and fatalities in Montana involving skiers, hunters, and climbers. Make sure you have avalanche rescue gear (shovel, beacon, and probe).  Hunters tend to travel solo without avalanche rescue equipment, and avalanches are most likely the last thing they are thinking of as they follow elk tracks across steep, open terrain.

If you see any of these obvious clues (listed below) signaling dangerous snow conditions, avoid being on or under open slopes steeper than 30 degrees.

  • Recent avalanche activity
  • Cracking or collapsing snowpack
  • Heavy snowfall
  • High winds
  • Rapid increase in temperature

If you spend any amount of time in the mountains in the winter, chances are good that you will encounter avalanche terrain.  Having basic awareness of terrain, weather and snow factors goes a long way toward making good decisions in avalanche terrain.  To assist you, we are offering several basic and advanced avalanche awareness classes this winter. We also have instructors available to provide your organization a range of programs from introductory lectures to classes with a field component.

Any information you can provide and send the WCMAC is appreciated and helps us inform the rest of the community about avalanche safety conditions. Please send a quick email to [email protected] or complete the form here public observation.

We will update the advisory as the weather dictates and plan to begin issuing regular avalanche advisories with a danger rating in mid-December.