Avalanche forecast

East Slopes Central

Northwest Avalanche Center
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Avalanche danger

Sun
Alpine
2 · Moderate
Treeline
2 · Moderate
Below
1 · Low
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Highlights

You can still trigger very large avalanches that break widely on deeply buried weak layers. Patience and terrain managment is essential. Continue to avoid traveling on or directly under steep, open slopes. Instead seek out smaller, well supported, low angle terrain.

Avalanche problems

  • Persistent Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible
    Size
    2–2.5

    This persistent slab problem is becoming slightly harder to trigger with time. But, it will also be extremely difficult to determine which slopes may slide and which won't, and if you and hit the wrong spot the result could be a very large and destructive avalanche . The Early February Crust (EFC) harbors weak, faceted snow and is now buried underneath a dense 2-4 foot thick slab. This recipe for avalanches exists on most middle and upper-elevation slopes.

    On Thursday, a snowbikers triggered two very large avalanches in the Teanaway. Earlier in the week, at least a couple of recent large avalanches were reported around the Blewett Pass area.  Also on Tuesday, a skier was partially buried in an avalanche on a NW aspect of Jim Hill in the neighboring Stevens Pass zone. These avalanches are failing 2-4ft deep, propagating widely, and being remotely triggered from low-angle terrain below or adjacent to steep slopes. You might not receive signs of instability before the whole slope fails. It could be the 2nd, 3rd, or 8th person on the slope that triggers it. 

    (3/7/2024)

    A snowbike triggered avalanche that occured on 3/7 in the Teanaway. This destructive avalanche likely failed on weak snow over the Early February Crust.

  • Wind Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible
    Size
    1–1.5

    An uptick in winds could form fresh, sensitive wind slabs near ridgelines, steep gullies, and the base of cliffs. While these avalanches may start small, they could step down to deeper weak layers, become very large, and break widely.

    Look for actively blowing snow, cornice formations, and textured surfaces to identify likely areas for wind slabs to be located. Steer around steep slopes where you identify stiff wind transported snow.

    (3/7/2024)

    Pillow-like drifts and textured surfaces like in this photo are a good visual clue of wind slabs.

    Photo: Katie Warren

Avalanche Discussion

NWAC is devastated to report the death of one of our Avalanche Forecasters, Matt Primomo. Tragically, Matt passed away in a non-avalanche accident away from work on Thursday, March 7th. Matt has been a key member of the NWAC family since 2017. His life in the mountains touched so many people. We are absolutely heartbroken. Please join us as we mourn this immense loss with Matt’s family, friends, and community.

Discussion:

Warmer temperatures could lead to some light rain or wet snow at the lower elevations. We don't expect it to be enough for a widespread wet loose avalanche problem, but you could see some fresh rollerball activity.

On Thursday, forecasters toured near Blewett Pass. They were able to see the recently triggered avalanche in Owl Creek from a distance, and they found variable test results that showed the persistent slab problem lingering. Tests and layer characteristics indicated that weak layers are slowly gaining strength. Our snowpack is complicated due to the intermittent dry spells in February. Besides the early February Crust, there are also potential layers of surface hoar and faceted grains from the 14th, 18th, and 24th. Widely propagating avalanches could fail on any of these layers. Approach the mountains cautiously and enjoy some low-angle powder until these weak layers gain strength.

This pattern of persistent slab problems can be challenging for backcountry decision-making. It takes conservative terrain management and patience. The structure is especially apparent in the eastern Cascades, where the snowpack is generally more shallow than at the crest. So, if you're venturing into these eastern zones, be prepared to take a step back in your typical terrain selection and understanding of the snowpack.

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