Avalanche Forecast
Issued: Apr 13th, 2023 4:00PM
The alpine rating is Loose Wet and Deep Persistent Slabs.
, the treeline rating is , and the below treeline rating is Known problems includeAvoid steep slopes that are getting baked in the sun, and use extra caution in thin, rocky start zones.
Dynamic spring weather means that avalanche danger could change quickly.
Observe your local conditions, and let that guide your terrain choice.
Summary
Confidence
Moderate
Avalanche Summary
Avalanches from earlier in the week are being reported as visibility improves, and people venture into the backcountry after the storm. As expected, there appears to have been a widespread avalanche cycle, with numerous large (size 2) and some larger (size 3) avalanches. Mostly storm slabs in the alpine, and wet loose at treeline and below.
A few avalanches likely started as storm slabs in the alpine, or just below a ridge, picked up loose wet snow, kept moving over dirt in some places, and ran down well into treeline, covering lower elevation hiking trails or forest roads.
If you head out in the backcountry, let us know what you are seeing by submitting a report to the Mountain Information Network.
Snowpack Summary
20-30 cm of settled surface snow in the alpine. Moist or refrozen surfaces on steep, solar aspects.
Below treeline, expect to find moist or refrozen surfaces, and shrinking snowpack depths.
The mid snowpack is generally settled and strong, except in areas with snow depths less than 150 cm. In these lower snow areas, the mid-pack is likely weaker and more faceted.
The lower snowpack includes a layer of large, weak facets and/or depth hoar crystals.
Weather Summary
Unsettled and convective weather could bring brief but intense periods of snowfall. Pinpointing these localized events creates a high level of uncertainty with this weather forecast. Prepare to continually evaluate the conditions, and change plans as necessary.
Thursday Night
Mostly cloudy. Trace-2 cm of snow expected, isolated areas of 10cm. Rain/snow line between 1500 m and 1000 m. Treeline low around -7°C. Light variable ridgetop wind.
Friday
Mostly cloudy. Possible trace of snow expected. Freezing level rising to 1700 m. Treeline high around -3°C. Light southwest ridgetop wind.
Saturday
Mostly sunny. No new snow expected. Freezing level at valley bottom overnight, rising to 2000 m. Light southwest ridgetop wind.
Sunday
Cloudy. 0-5 cm of snow expected. Freezing level at 1500 m overnight, rising to 2000 m. Light southwest ridgetop wind, trending to strong at high elevations.
More details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- Be alert to conditions that change with aspect and elevation.
- Watch for unstable snow on specific terrain features, especially when the snow is moist or wet.
- Avoid thin areas like rock outcroppings where you're most likely to trigger avalanches failing on deep weak layers.
Problems
Loose Wet
During periods of daytime warming and sunshine, expect the surface snow on aspects that face the sun to become unstable.
If you see signs of loose wet instability, like snow that feels like a slurpy, or clumps up and pinwheels down a slope, move to less steep and more shaded terrain.
Aspects: South East, South, South West, West.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Deep Persistent Slabs
The base of the snowpack remains weak. Avoid thin, rocky start zones and shallow areas with variable snowpack depths.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Apr 14th, 2023 4:00PM