Issued: Apr 16th, 2023 4:00PM
The alpine rating is Loose Wet and Wind Slabs., the treeline rating is , and the below treeline rating is Known problems include
Increased daytime warming and sunshine will rapidly settle and increase the sensitivity of triggering avalanche problems. Avoid large open connected terrain on solar aspects during periods of intense sunshine.
Watch for unstable snow on isolated features: windslabs in the high alpine, and loose wet avalanches on steep slopes that face the sun.
Expect variable snowpack conditions as we transition from winter to spring.
No new avalanches were reported before 4 pm on Sunday.
We expect that anywhere that was sunny on Thursday or Friday would have seen numerous, small, wet loose avalanches triggered by the sun on steep slopes. Also, there may be small pockets of windslab on exposed alpine ridges that could avalanche under the weight of a human.
If you have any observations from this region, let us know what you are seeing by submitting a report to the Mountain Information Network.
In the alpine and around treeline, 5-10 cm of new snow covers a frozen crust, with moist snow below.
The mid snowpack is generally settled and strong at treeline and above.
A melt-freeze crust that was buried in mid January can be found 60 to 100 cm below the snow surface.
A weak layer of large, sugary crystals persists at the base of the snowpack. This layer has not produced recent avalanche activity in this area, but professionals continue to monitor for signs of it becoming active.
Cloud with light snowfall. 5-10 cm of snow expected in the alpine. Freezing level descending to 1400 m. Treeline low around 0 °C. Strong to moderate southwest ridgetop wind.
Mix of sun and cloud . No new snow expected. Freezing level rising to 1800m. Treeline high around 2°C. Strong easing to light southwest ridgetop wind.
Partly cloudy. Trace amounts of new snow in the alpine. Freezing level at 400 m overnight, rising to 1600 m. Moderate southwest ridgetop wind.
Mostly clear, no new snow expected. Freezing level falling to valley bottom at night and rising to 1700 m mid day. Treeline low around -6 °C Moderate to light southwest ridgetop wind.
More details can be found in the Mountain Weather Forecast.
Terrain and Travel Advice
- Watch for unstable snow on specific terrain features, especially when the snow is moist or wet.
- Be alert to conditions that change throughout the day.
- Be alert to conditions that change with aspect and elevation.
- Use caution above cliffs and terrain traps where even small avalanches may have severe consequences.
During periods of daytime warming and sunshine, expect the surface snow to be unstable on slopes that face the sun.
A wet storm added a lot of moisture and heat to the upper snowpack earlier this week.
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.
New snow, combined with strong winds will build new windslabs. Expect this problem to become sensitive to light triggers, once the temps rise and sun kisses the snow surface.
Carefully evaluate for windslab hazard before committing to bigger features.
Aspects: North, North East, East, South East, North West.
Valid until: Apr 17th, 2023 4:00PM