Avalanche forecast

Mount Shasta

Mount Shasta Avalanche Center
View on map

Avalanche danger

Tue
Alpine
2 · Moderate
Treeline
2 · Moderate
Below
1 · Low
Open full map
Out of date — this forecast expired 3 years ago. You’re viewing past conditions, not the current bulletin.

Highlights

Today, an approaching warm front will bring light snowfall and strengthening winds out of the northwest. Heightened avalanche conditions exist near and above treeline, where already existing wind slabs are increasing in size and sensitivity. Human triggered avalanches are possible. Careful evaluation of terrain and snow stability will be the key to safe travel. 

Avalanche problems

  • Wind Slabs

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

    This problem is constrained to E-SE-S aspects at upper elevations. The last 12 hours presented a slight reprieve in winds, mainly light to moderate out of the southeast. However, the amount of wind loading from the recent northwest winds is still the issue, to which will pick back up today. Near and above treeline, wind slabs can still be initiated with ease under the weight of skis. Above treeline, exposed slopes and ridges have been stripped down to the old snow crust, often completely devoid of the new snow. That being said, the potential remains for a large wind slab in extreme terrain on the upper reaches of Mount Shasta. If triggered, these slabs could break up to 2 feet deep, carry, and bury you. Keep your eyes peeled for signs of instability such as shooting cracks, collapsing slopes, and whumpfing.

    (1/6/2024)

    Wind slab below treeline

    Photo: Samuel Clairmont

Avalanche Discussion

Today marks the beginning of another winter storm system. NWS Medford has issued a Winter Storm Warning for Siskiyou county from 1am Tuesday until 4pm Wednesday. A warm front will enter the region today, bringing light snow, and elevated wind speeds. Most of the significant action will begin late tonight. By midnight, snow will begin to fall at moderate rates and northwesterly winds will blow strong at low elevations. Near and above treeline, winds are expected to reach gale force (>38 MPH) for at least the next 24 hours. 

This storm system will bring poor visibility, blowing snow, and extreme snow surface variability for exposed areas across Mount Shasta.  If you're venturing up high today, prepare for changing weather conditions and challenging snow surfaces. At the moment, above treeline terrain is already stripped of soft snow, with lots of rock exposed. Snow surfaces include wind board, occasional soft snow, surface crusts, and sastrugi.

Regarding the snowpack, this system will surely spike instability. The bulk of the system will be slamming areas north of us, with Mount Shasta only experiencing the southern flank. But depending on how this system tracks, we could see more snow than expected. This system will likely favor our westerly terrain, such as the Eddies and Castle Lake. As snow falls and wind increases, wind transported snow will add to the already wind loaded areas, further straining the stability of the snowpack. Again, most of this will only occur late tonight into tomorrow.

Regions covered