Avalanche Advisory: Saturday - Jan 2, 2021

THIS AVALANCHE ADVISORY EXPIRED ON January 3, 2021 @ 6:14 am
Avalanche Advisory published on January 2, 2021 @ 6:14 am
Issued by Steve Mace - ESAC

MODERATE avalanche danger exists today at mid and upper elevations. Wind slabs will be the primary concern on all aspects near and above treeline, particularly in areas at the mid-elevation band with loose surface snow available for transport. Evaluate snow and terrain carefully if you head into the backcountry today and be wary of the very thin obstacle-ridden conditions.

2. Moderate

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Above Treeline
Heightened avalanche conditions on specific terrain features. Evaluate snow and terrain carefully; identify features of concern.

2. Moderate

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Near Treeline
Heightened avalanche conditions on specific terrain features. Evaluate snow and terrain carefully; identify features of concern.

1. Low

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Below Treeline
Generally safe avalanche conditions. Watch for unstable snow on isolated terrain features.
    Heightened avalanche conditions on specific terrain features. Evaluate snow and terrain carefully; identify features of concern.
Avalanche Problem 1: Wind Slab
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    Certain
    Very Likely
    Likely
    Possible
    Unlikely
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    Historic
    Very Large
    Large
    Small

The wind shifted again last night back to an SW flow and spent much of the evening blowing at Strong to Gale force speeds. We may see the wind speed drop a bit for the daylight hours today but they're likely to remain in the 20-50 mph range. Despite the renewed strong winds, we do not expect significant new slab development today. Upper elevations are not holding a substantial amount of loose snow at the moment. Recent strong winds have already stripped much of the alpine and solar aspects received a good dose of settlement yesterday. Older more stubborn slabs may still be reactive to human triggers on all aspects. It is also important to remember that strong winds can distribute snow in unexpected ways. Don’t be surprised to find wind deposits at lower elevations and further down slopes than you may typically expect to find them. Areas that still hold loose surface snow in the mid-elevations band may be most problematic today. Do your own localized assessments and be suspect of terrain features that encourage drifting such as the leeward sides of ridgelines, gully features, and cross-loaded depressions Use surface clues such as blowing and drifting snow, recent cornice growth, and uneven snow surfaces to help you identify and avoid areas of recent wind deposit.

advisory discussion

Quite weather and time have been helping to strengthen the upper snowpack, and we expect this trend to continue over the next two days before we see a significant change in pattern. However, now is not the time to become complacent. It remains important to track the state of the weak and complex underlying snowpack and be ready for a significant spike in avalanche danger when we see a significant new load.

In addition, the shallow and sporadic coverage continues to pose serious hazards to backcountry enthusiasts. Recent observations from across the range continue to highlight the shallow and obstacle-ridden conditions.  Slow it down and move with caution. The sharks are everywhere, lurking just below the surface.

Weather and CURRENT CONDITIONS
weather summary

Expect mostly cloudy skies and mild temperatures today. Highs are expected in the low to mid 30°F.  Winds have shifted back to the SW and increased in speed. Expect moderate to strong winds with very strong gusts even at lower elevations.

We expect this relatively mild weather to continue through the weekend before we see a change in pattern on Monday as a strong winter storm impacts the Sierra. The QPF has been downgrading steadily as this storm has grown closer but we may still see significant snow totals over the next week.

Two-Day Mountain Weather Forecast Produced in partnership with the Reno NWS
For 8,000 ft. to 10,000 ft.
Saturday Saturday Night Sunday
Weather: Mostly cloudy. Snow levels below 7000 feet. Mostly cloudy. Snow levels below 7000 feet. Mostly cloudy. Snow levels below 7000 feet increasing to 7500 feet in the afternoon.
Temperatures: 30 to 38. deg. F. 21 to 26. deg. F. 34 to 40. deg. F.
Mid Slope Winds: Southwest 15 to 25 mph with gusts to 45 mph. Southwest 15 to 25 mph with gusts to 45 mph. Southwest around 15 mph in the morning becoming light. Gusts up to 40 mph.
Expected snowfall: 0 in. 0 in. 0 in.
Over 10,000 ft.
Saturday Saturday Night Sunday
Weather: Mostly cloudy. Snow levels below 7000 feet. Mostly cloudy. Snow levels below 7000 feet. Mostly cloudy. Snow levels below 7000 feet increasing to 8000 feet in the afternoon.
Temperatures: 24 to 30. deg. F. 17 to 22. deg. F. 27 to 33. deg. F.
Ridge Top Winds: Southwest 15 to 30 mph. Gusts up to 50 mph decreasing to 40 mph in the afternoon. Southwest 20 to 35 mph with gusts to 55 mph. West 15 to 30 mph. Gusts up to 50 mph decreasing to 40 mph in the afternoon.
Expected snowfall: No accumulation. | SWE = none. in. No accumulation. | SWE = none. in. No accumulation. | SWE = none. in.
Disclaimer
This Avalanche Advisory is designed to generally describe avalanche conditions where local variations always occur. This product only applies to backcountry areas located outside established ski area boundaries. The information in this Avalanche Advisory is provided by the Eastern Sierra Avalanche Center, who is solely responsible for its content.

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