Avalanche forecast

Snoqualmie Pass

Northwest Avalanche Center
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Avalanche danger

Fri
Alpine
3 · Considerable
Treeline
3 · Considerable
Below
2 · Moderate
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Highlights

Snow, wind, and slowly rising freezing levels should combine to create slab avalanche problems for you to manage on Thursday.  Avalanche potential could rise and fall with the weather throughout the day, so constantly reassess the upper snowpack for stability. When in doubt, avoid slopes over 35 degrees where triggering a slab is more likely.

Avalanche problems

  • Storm Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Likely
    Size
    1–2

    We're back into stormy conditions, meaning new snow problems will again take center stage. Look for unstable slabs on slopes over 35 degrees, particularly if they're convex or wind-loaded. Thursday will be sandwiched between two storm pulses, so the reactivity of storm slabs may be greatest during periods of precipitation first thing in the morning or the late afternoon. However, the wind should fill the void between storm systems mid-day, so you could find that the new snow drifts into fresh slabs on leeward slopes during this time. No matter how you look at it, it's shaping up to be a dangerous day in the mountains where new snow falls on various surfaces and has waxing and waning reactivity. Use small test slopes, hand pits, or uptrack tests to gauge the slab potential of the new snow. If blocks of snow fail easily in your tests, choose simpler or more treed terrain where the consequences of a slab avalanche could be less.

    (3/18/2025)

    This soft slab avalanche was triggered by a skier on a steep rollover on Tuesday near Bryant Peak. The skier was caught and carried, but fortunately not buried or harmed. It occurred the morning after overnight snowfall.

Avalanche Discussion

Miracle March is set to continue for winter enthusiasts, making the first day of spring feel more like winter. Thursday should be the start of a multi-day storm pattern that will see snowfall, wind, and slowly rising temperatures. As snow accumulates, expect avalanche potential to slowly increase as we head into the weekend. Once temperatures increase, expect rain to make its way into the Western half of the zone and eventually the Pass proper and eastern portions of the zone, resulting in wet avalanche potential at lower elevations. This may not happen until Friday.

This past week has been stormy, with measurable precipitation every morning since the 12th, except for our lull on Wednesday. It's added up to several feet of new snow, which has resulted in several rounds of avalanches. While we aren't specifically calling out any particular layers in the upper snowpack as problematic, some recent interfaces may still need time to heal. The recent snow has generally been low-density, and these incoming warmer storms may result in an upside-down snowpack. Periods of clear weather have created subtle melt-freeze crusts on slopes that see direct sunshine, and convective springtime showers have resulted in graupel that can act as a weak layer. And then there's the wind. Throughout our snowy week, the wind has easily drifted the low-density snow into drifts on leeward slopes, creating unstable slabs. They should be on the mend, but those who haven't fully healed will be hidden beneath the fresh new snow, making them hard to assess. Add it all up, and the upper snowpack over the atmospheric river (AR) crust is variable in depth, as well as the number of subtle crusts found. Not all slopes will act the same.

These factors have been at play over the last week. Multiple parties have triggered avalanches, and a handful have been caught and carried. Since last Thursday, we have had a report of an avalanche involvement every day around the state. This includes the general public and avalanche professionals alike. Many of these groups reported being surprised, caught off guard,  or lulled into a false sense of stability. Some have said that the current avalanche landscape is "sneaky." No matter what term you use to describe the situation, note that avalanche activity and involvements have risen, and now we're heading back into a stormy pattern. 

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