Avalanche forecast

East Slopes Central

Northwest Avalanche Center
View on map

Avalanche danger

Mon
Alpine
2 · Moderate
Treeline
2 · Moderate
Below
2 · Moderate
Open full map
Out of date — this forecast expired 4 years ago. You’re viewing past conditions, not the current bulletin.

Highlights

Variable, weak, and slick old snow surfaces exist, and triggering avalanches in new snow is possible. Avalanches may be large in areas where winds drift the snow deeper, and a firm sun crust may make avalanches on steep southern aspects more likely. If small test slopes produce small slabs or shooting cracks, you should steer around steep terrain. 

Avalanche problems

  • Wind Slabs

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

    The forecast calls for light snow with moderate winds overnight, and into Sunday, there is still potential for triggering a wind slab at upper elevations. We have limited information on how well new snow is bonding with underlying weak or slick surfaces. But the most hazardous areas likely exist where the wind has formed deeper slabs of snow near ridgelines, rocky outcrops, or confined gullies at upper elevations. Actively blowing snow, textured surfaces, and drifts behind objects can help you identify which slopes may have fresh wind slabs. Use can also use your probe or pole to feel for stiff layers of snow over softer layers, and quick hand pits can show you how easily this stiffer snow will slide. Shooting cracks in wind-stiffened snow are a warning to avoid these wind-loaded areas. Steer around steep slopes where you find evidence of sensitive wind slabs or stick to wind-sheltered terrain. 

    (1/3/2023)

    These cornices with pillow-like drifts before are evidence that wind slabs are present on the slopes below.

    Photo: Katie Warren

  • Storm Slabs

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

    7-8 inches of snow fell in most places throughout East Central on Saturday. Recent snow and wind buried weak surfaces and slick crusts, and there have been limited and inconsistent observations on snow stability in the East Central Zone. There is uncertainty regarding the quality of the bond with the old surfaces. Observations from South facing aspects near Lake Wenatchee indicated a weak interface (1/4), with new snow sliding easily on the underlying melt-freeze crust formed during clear sunny weather over New Year's weekend. Be particularly cautious in these southern aspects, where you may easily trigger avalanches that run far on this slick crust. Quick hand pits and small test slopes are great ways to investigate this recent snow interface. Steer around steep slopes where new snow slides easily, or steep test slopes produce small slabs.Below 3000ft, wet loose avalanches running on crusts may be possible with daytime warming. Look for signs of rollerballs or wet snow surfaces to identify the potential for wet loose avalanches.

    (12/20/2022)

    Small steep test slopes like this are great for testing out how well new snow bonds to old surfaces. 

    Photo: Public Observation

Avalanche Discussion

Observations from Blewett Pass and Mission Ridge on Thursday and Wedge Mountain on Friday were of 3-5 inches of new snow that was largely unreactive, even in wind loaded areas. However, very different conditions existed on South-facing aspects near Lake Wenatchee, where new snow slid easily and ran far on the underlying melt-freeze crust. This variable and potentially weak interface (1/4/23) from Wednesday night's storm will be one to watch with this next round of snow in the forecast for tomorrow. At lower elevations on Saturday, the WSDOT avalanche crew reported wet loose avalanches occurring naturally in Tumwater Canyon's steep terrain. 

Other surfaces that recent storm snow buried and are contributing to the complicated snowpack are below.-Wind stiffened snow in exposed terrain near ridges at upper elevations.-Sun crusts on southern aspects.-Rain or Freezing fog melt-freeze crusts at lower elevations.-Weak, faceted snow and surface hoar in sheltered northern locations.

Regions covered