Avalanche forecast

Mount Shasta

Mount Shasta Avalanche Center
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Avalanche danger

Thu
Alpine
1 · Low
Treeline
1 · Low
Below
1 · Low
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Highlights

Weather and avalanche conditions will transition today. An approaching storm will increase the risk of wind-drifted snow above treeline later in the forecast period. Until then, the chance of encountering wet loose snow near and below treeline remains low on all aspects. Avoid steep slopes with saturated surfaces. General caution is advised.

Avalanche problems

  • Loose Wet

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

    Temperatures have begun to drop with the approaching storm system, reducing the likelihood of wet loose instabilities. That said, a touch of caution is still advised in steep terrain near and below treeline, where wet snow could prove problematic in the wrong spot.

    Overnight temperatures have remained above freezing, but are expected to decrease throughout the day. While this trend will help stabilize wet snow surfaces, isolated pockets may remain. Rain falling on snow is a red flag of avalanche danger. If you observe this, it's best to avoid steep slopes, as the added water weight can cause rapid instabilities. 

    One way you can evaluate slope stability is by throwing a snowball down hill and seeing if it collects, gouges, or entrains surrounding snow. Also, if you can wring out liquid water from a snowball, that's a tell-tail sign the surface is too wet. 

    Snowmobile triggered D1 wet-loose on east face of Green Butte 

    Photo: Eric Falconer

  • Wind Slabs

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

    This precautionary problem won't fully take effect until later this evening and tonight, when new snowfall will be accompanied by strong south-southwest winds. These conditions will form new drifts on leeward north and east aspects above treeline, increasing the avalanche danger. Avoid slopes receiving actively blowing snow and newly forming wind lips. 

Avalanche Discussion

Hope no one’s tired of winter yet! Southwest flow will deliver another Shasta classic starting tonight, with peak storm intensity Thursday. Expect increased avalanche danger moving forward. Say goodbye to the wet loose avalanche problem and hello to wind slabs and storm slabs.

A few notes on the incoming storm: It will follow a warming-to-cooling trend, which will promote good bonding. The majority of bed surfaces throughout the forecast area are smooth and untextured, which is a positive and somewhat rare.

The downside, however, is the wind. Strong to extreme wind speeds are possible during the storm, and our beloved volcano is very exposed. Reminder, wind can transport snow five times faster than it can fall from the sky, and can scour old snow surfaces down to bare earth in a matter of hours. This will create wind slabs. Lastly, the storm's onset tonight may bring thunderstorms. Thunderstorms can produce graupel, a type of precipitation that, if buried, can contribute to avalanche problems. While I don’t expect this to be very likely, it’s something to watch. Stay tuned to the forecast for the most up-to-date information.

The Everitt Memorial Highway and Castle Lake roads are closed.

Regions covered