Solar Aspects - High pressure off the coast of California continues to deflect storms to the north of the forecast region and usher in exceptionally warm daytime temperatures (10 to 20 degrees above average) while overnight temperatures struggle to fall below freezing in many locations. With the spring like weather, the snowpack is experiencing daily thaws where the free water breaks down the bonds between snow grains and layers within the snowpack. As this process continues, the snow looses internal strength and cohesion; if the mass of the snow exceeds the snow strength, a Loose Wet or Wet Slab avalanche occurs. The threat of wet instabilities on solar aspects (E-S-W) will be with us for the foreseeable future as long as the high-pressure ridge remains locked in place of the California coast. With the limited snow coverage, the exposed rocky terrain features can introduce tremendous amounts of heat into the snowpack and cause rapid localized thawing in cirques and gullies. Timing your travels to be out of steep sunny terrain before the snow thaws from the heat of the day is key to avoiding wet instabilities.
Northerly aspects - the primary avalanche problem is the persistent weakness from lingering facets that formed early season and are now buried ~30 to ~60cm (12” to 24”) from the surface. On the northerly aspects the snowpack remains cool but is showing signs of warming, at least at the surface with some mid elevations warming and forming a thin melt freeze crust. Otherwise the snow is still somewhat soft in sheltered areas near treeline but aspect and shading is key. In steep sheltered terrain, isolated Loose Dry sloughs may be triggered where the snow is disturbed or a small isolated suspended Wind Slab could fail if a sufficient trigger is applied.
Below ~9,000’, natural and triggered releases are unlikely due to thin and well-anchored snow coverage (below threshold).
* Caution - Firm snow conditions on southerly aspects in the AM can produce slide-for-life conditions. A minor slide into hazardous terrain can have serious consequences.