Loose Wet
- Alpine
- Treeline
- Below treeline
- Likelihood
- Likely
- Size
- 3
Mountain temperatures will climb into the mid-60s °F following a weak overnight refreeze. The window for safe travel is very small this morning. Once superficial crusts melt, expect to be able to trigger wet-loose avalanches that, although they may be relatively slow-moving, can gouge down and entrain a large volume of snow as they slide.
The potential for wet slabs to release will increase through the day as the snowpack warms and meltwater begins moving through the snowpack. Wet slabs are generally more destructive and more difficult to manage than wet-loose avalanches; they can break widely without clear warning signs. When meltwater percolates into the snowpack, it pools on buried crusts or faceted layers, weakening bonds and resulting in wet slab avalanches several feet thick. There is a high amount of variability and uncertainty in predicting wet slabs. Give yourself a wide safety margin to handle the uncertainty by choosing conservative terrain, avoiding travel on and beneath steep slopes, and planning an early exit from the mountains.
Additional wet-snow problems:
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Glide avalanches: These full-depth, destructive slides are difficult to forecast. It’s worth avoiding areas where the snowpack exists above smooth ground vegetation or smooth rock slabs.
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Cornices: Warm temperatures cause cornices to slump and bend, eventually falling off the ridgeline naturally in the spring. Avoid traveling on or beneath ridgelines where cornices hang overhead.