Avalanche Forecast
Dec 31st, 2018–Jan 1st, 2019
Alpine
2:
Moderate
The avalanche danger rating in the alpine will be moderate
Treeline
2:
Moderate
The avalanche danger rating at treeline will be moderate
Below Treeline
2:
Moderate
The avalanche danger rating below treeline will be moderate
Alpine
2:
Moderate
The avalanche danger rating in the alpine will be moderate
Treeline
2:
Moderate
The avalanche danger rating at treeline will be moderate
Below Treeline
2:
Moderate
The avalanche danger rating below treeline will be moderate
Regions: Cascades - West.
The Bottom Line: Happy New Year! Sunshine and cool weather will usher in the New Year, but avalanches are happening in unusual ways, so it’s not a time to be complacent. You may still trigger avalanches in wind loaded areas. In some locations wind deposited snow may sit on a layer of weak buried surface hoar. If you experience collapsing, cracking in the snow, or see recent avalanches, avoid open slopes 30 degrees or steeper.
Avalanche and Snowpack Discussion
Several natural and human triggered avalanches were reported in the adjacent north zone in Schrieber’s Meadow and Heather Meadows areas on Sunday. Many of these avalanches were unusual. They propagated widely, had thin crowns, released low on the slope, and/or failed on lower angled slopes. When we see signs like this, it calls attention to buried surface hoar. Human triggered avalanches in other zones have failed on a similar layer.
Avalanche Problems
Wind Slabs
Wind slabs formed over the weekend are gaining strength, but have not fully healed. Backcountry travelers and local professionals reported finding wind slabs in unusual locations such as low on the slope and in areas often wind-stripped. You may still trigger wind slabs on convex rollovers, near the sides of cross-loaded gullies, and on wind drifted snow well below ridgeline. In some locations, wind drifted snow may sit over a layer of buried surface hoar. In these locations, an avalanche may propagate widely and surprise you by extending long distances.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood: Possible
Expected Size: 2 - 2
Persistent Slabs
New reports are garnering more evidence that a layer of buried surface survived the recent storms. It’s tough to say exactly where this layer is present. Buried surface hoar can be difficult to manage because it is often very spotty across the landscape. Here’s what we know. A natural avalanche cycle occurred on this layer over the weekend in the Baker area. Backcountry travelers triggered avalanches on this layer Sunday and Monday in other zones. We suspect this layer is found 1-2 ft below the surface on NW-SE aspects above 4500 ft. Reported avalanches have been very unusual failing on low angled slopes (30-35 degrees), propagating widely, and releasing low in the startzones. This is a good time to break out the shovel and dig. Snow profiles can confirm the presence of surface hoar, but they cannot prove its absence. Less specific information has been received from this zone, so extra caution is warranted.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood: Possible
Expected Size: 2 - 2