West Slopes South

Minimal precipitation and mild temperatures won’t be enough to create much in the way of avalanche danger on Monday in the West South zone. However, you may still find a few very isolated pockets on unstable snow, particularly in wind-exposed terrain.

Clear skies most of Sunday night should allow the wet snow from this weekend to freeze solid. The weather will have a hard time breaking down this crust or creating a wet surface in lingering pockets of dry snow. As a result, you should find generally safe avalanche conditions. Even with temperatures above freezing, frozen snow surfaces won’t significantly soften without the help of the sun. Strong winds will also aid in keeping the surface cool, especially at mid and upper elevation. Finally, we’re not expecting much in the way of precipitation, so while some of it may fall as rain, it won’t be enough to form wet snow problems. As you can see, the avalanche danger hinges significantly on the weather forecast. If the sun comes out in the afternoon or significantly more precipitation falls than expected, the hazard could be rising. 

You’re most likely to find an isolated pocket of unstable snow in wind drifted areas at mid and upper elevations. After a few sunny days and several wind events this past week, there just isn't much snow to blow around and form new wind slabs. This will limit the size and distribution of this potential problem.  Keep your eyes peeled for firm smooth pillow-like drifts. Steer around these features on steep slopes. 

One of the biggest questions on Monday is will the sun make an appearance? While you may see some sun breaks, particularly further south in the zone, they likely won’t be enough to weaken the surface. However, if you find wet snow, be it from rain, temperatures, or sun, start to anticipate loose wet avalanches. New rollerballs are a great clue that the snowpack is heading in this direction. When you see this observation, be leery of similar steep slopes. 

While the avalanche danger may be Low, there is still a weak snowpack structure in some locations. The Late January crust/facets is frequently found just below the recent snow on shaded slopes. An NWAC forecaster on Mt Adams Sunday confirmed its presence in that area. This adds to our list with observations of this layer near Crystal, White Pass, Mt Rainier, and Mt Adams. So far, we haven’t seen or heard of any avalanches at this interface in the West South zone and snowpack tests have been inconsistent. Further north, several avalanches, large collapses, and sudden test results continue to occur. We’ll keep our eye on this layer going forward. 

This weekend’s warm and sunny weather caused some changes to the snowpack. On Sunday a large cornice failed naturally near Paradise on Mt Rainier. While cornices aren’t as large as normal, they still pose a hazard particularly during warm and sunny periods. This is a reminder to pay attention to what’s above you and not to linger under these features. Despite the spring-like weather, cold dry snow still persists on shaded slopes. As you travel Monday, you may find a highly variable snow surface with breakable crust, icy slopes, wind-textured surfaces, wet heavy snow, and dry powder.