Avalanche forecast

Central Sierra Nevada

Sierra Avalanche Center
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Avalanche danger

Tue
Alpine
4 · High
Treeline
4 · High
Below
4 · High
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Highlights

An intense pulse of snowfall is expected to deposit another foot of new snow this morning. This combined with strong winds will fuel ongoing snowpack instability and keep natural avalanches very likely today. Travel in, near, or below avalanche terrain is not recommended.

Avalanche problems

  • Wind Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Very Likely
    Size
    1.5–3

    Wind direction has varied from SE to SW during this storm, increasing the distribution of wind slabs. Strong SW winds this morning combined with another round of high intensity snowfall will rapidly load new snow onto the downwind side of ridgetops and into gully features. New wind slabs will form on top of existing wind slabs that have been reactive over the past two days. Some avalanches could become fairly large, potentially depositing debris down near the valley floor.

    If traveling non-avalanche terrain today, expect poor visibility, especially during the morning hours. Plan your method for avoiding exposure to avalanche terrain above you when you cannot see it.

    (2/4/2024)

    Photo of remotely triggered avalanche from point of trigger. Slope is NNW aspect. Fireplug/Galena Bowl near Mount Rose Hwy, NV. Photo: Public

  • Storm Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Very Likely
    Size
    1–2

    Natural and human triggered storm slab avalanches were widespread yesterday due to the upside-down layering within yesterday's new snow. Reports of substantial amounts of graupel (pellet snow) were also received yesterday. These weak layers may remain unstable today. If yesterday's weak layers remain reactive today avalanche size will be larger. There may also be a new rain crust within the storm snow below about 6,500 to 7,300' due to rising snow levels late yesterday.

    Regardless, another round of high intensity snowfall this morning with snowfall rates up to 3 inches per hour is expected to continue to produce unstable storm slabs. Storm slab avalanches are very likely again today in wind protected areas below treeline.

    If traveling non-avalanche terrain today, pay close attention to slope angles. Keep travel limited to slopes well below the 30 degree slope angle threshold for avalanche terrain and without steeper connected terrain above or to the side.

  • Deep Persistent Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Likely
    Size
    2–3

    In isolated areas along the eastern side of the forecast area, there remains relatively weak, faceted (sugary) snow in the lower portion of the snowpack. Widespread collapsing and whumpfing were reported yesterday from terrain near Tamarack Peak off the Mount Rose Hwy. This storm appears to have deposited enough new snow load to reactivate deep weak layers along the eastern side of the forecast area. Any deep persistent slab avalanches that occur have the potential to be long running, large, and destructive.

Regions covered