Southeast Mountains

Quiet weather and a strengthening snowpack allow safe travel through most avalanche terrain.  Stay alert for isolated instabilities, especially in very steep, rocky, or extreme terrain.  These include shallow wet sluffs on sunbaked slopes as the day warms up and lingering large slabs on high, northerly aspects where the snowpack is unusually shallow.   Guard against surprises by reducing your exposure during uphill travel, traveling one at a time in avalanche terrain, and carrying rescue gear.  

A lack of natural or human-triggered wind slabs over the weekend, followed by the last two days of quiet weather, suggests the wind slab problem is becoming increasingly difficult to find and trigger.  This observation from Purple Ridge yesterday highlights how wind slabs that formed on northerly aspects may persist longer on a few features.  On those same high, northerly slopes, the snowpack has remained dry and winter-like, preserving the threat of a rare but dangerous persistent slab. The relatively quiet weather since our late March storm has allowed deeper weak layers to adjust: signs of instability and stability tests have shown significant improvement in the last week. Our last persistent slab was triggered on April 3rd.  The most likely terrain to encounter a lingering persistent slab is where the snowpack has remained unusually shallow and weak all winter. On northerly aspects, seek out slopes with deep and uniform snow depths to reduce your risk of a low-likelihood, high-consequence avalanche.  

The most recent snow (about 5" to 10" on Saturday favoring the Northwest Mountains) will continue to transition from dry powder to wet snow causing some shallow wet loose instabilities on sun-baked slopes as the day warms up.  Given the relatively cooler temps this week compared to last, entrainment potential is limited to just the fresh snow over hard crusts below.  Although these sluffs will be relatively small, they can still knock you over or take you for a ride. Yesterday, a skier was carried in a small wet loose avalanche on Snodgrass.  In high-consequence terrain, this could have had a different outcome.  Use sluff management techniques or time your travels to avoid very steep slopes above terrain traps after they get too warm and wet.  

After a season plagued by persistent weak layers, it has been over three months since we saw Low danger in both forecast zones.  Conditions are appropriate for traveling in more complex avalanche terrain, but low danger does not mean no danger.  Your avalanche risk is a product of the hazard and how much exposure and vulnerability you take on.  Look for ways to reduce your exposure to potentially problematic slopes and continue to practice sound travel practices like traveling one at a time in steep terrain, carrying rescue gear, etc.