Avalanche Advisory: Wednesday - Feb 6, 2019

THIS AVALANCHE ADVISORY EXPIRED ON February 7, 2019 @ 6:38 am
Avalanche Advisory published on February 6, 2019 @ 6:38 am
Issued by Steve Mace - ESAC

Avalanche danger remains HIGH today at upper elevations while dropping to CONSIDERABLE at lower and mid elevations.  Large sensitive wind slabs will be the primary concern today though it may still be possible to find storm slabs sensitive to human trigger.  Dangerous avalanche conditions exist; travel in avalanche terrain is not recommended.

4. High

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Above Treeline
Very dangerous avalanche conditions. Travel in avalanche terrain not recommended.

3. Considerable

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Near Treeline
Dangerous avalanche conditions. Careful snowpack evaluation, cautious route-finding and conservative decision-making essential.

3. Considerable

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Below Treeline
Dangerous avalanche conditions. Careful snowpack evaluation, cautious route-finding and conservative decision-making essential.
    Very dangerous avalanche conditions. Travel in avalanche terrain not recommended.
Avalanche Problem 1: Wind Slab
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 Wind speeds will be significantly lower today than they have been for the past few days, but they are forecasted to be within the ideal range for loading.   Couple this with a large amount of new snow available for transport; expect sensitive wind slab avalanches in areas where terrain encourages drifting.  Size and distribution of wind slabs will be mixed today, expect slabs to range from small to very large.  While the most sensitive slabs will likely be on easterly aspects at upper elevations it will be possible to find wind slabs sensitive to human trigger on other aspects and at mid elevations. Use surface clues such as new cornice growth, blowing snow, and uneven snow surface to identify and avoid wind-loaded areas.  

Avalanche Problem 2: Storm Slab
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Over 7’ of new snow has been added to the snowpack in the last four days. While storm slabs have a relatively short life span, it is important to give things time to settle. While triggering a storm slab avalanche will become more difficult as time moves on a resulting avalanche is likely to be large.   Be particularly wary of steep sheltered terrain over 35°, especially in areas where terrain traps are present.

 

Avalanche Problem 3: Loose Dry
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With temperatures continuing to be very cold surface snow is likely to settle slowly.  Loose dry avalanches will be possible in steep terrain today.   These unconsolidated sloughs could easily be large and entrain enough snow to carry a skier through unpleasant terrain.  Be cautious in sheltered terrain over 35°. ​

advisory discussion

Don’t let the blue skies and fresh snow lure you into making bad decisions today.  High avalanche danger still exists throughout the range. Large human triggered avalanches are likely and have the potential to run long distances into areas usually thought of as safe.  Be aware of adjacent terrain including what is above you.  Keep in mind that travel in these conditions is an arduous task and with the sheer amount of unconsolidated snow an otherwise benign fall comes with the risk of deep snow emersion and could prove deadly. Keep your friends close and be cautious if heading out into the backcountry today. 

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Weather and CURRENT CONDITIONS
weather summary

Expect partly cloudy skies this morning becoming sunny this afternoon.  Temperatures will remain cold with highs in the mid teens at upper elevations.  Winds will be moderate out of the northwest with ridge top gusts to 50 mph.

Tonight will be clear and cold with temperatures dropping below zero and moderate winds continuing out of the northwest.  Things should warm up slightly with highs in the low 20s tomorrow as diminishing winds shift back to the southwest.  

Another storm system bringing light to moderate snow is expected to move through the region this weekend.

Two-Day Mountain Weather Forecast Produced in partnership with the Reno NWS
For 8,000 ft. to 10,000 ft.
Wednesday Wednesday Night Thursday
Weather: Partly cloudy then becoming sunny. Clear. Sunny then becoming partly cloudy.
Temperatures: 18 to 24. deg. F. 1 to 7. deg. F. 25 to 31. deg. F.
Mid Slope Winds: West 15 to 20 mph with gusts to 45 mph. Northwest around 15 mph with gusts to 40 mph in the evening becoming light. Light winds. Gusts up to 25 mph in the afternoon.
Expected snowfall: None in. None in. None in.
Over 10,000 ft.
Wednesday Wednesday Night Thursday
Weather: Partly cloudy then becoming sunny. Clear. Sunny then becoming partly cloudy.
Temperatures: 11 to 16. deg. F. 2 below to 4 above zero. deg. F. 18 to 23. deg. F.
Ridge Top Winds: Northwest 15 to 30 mph with gusts to 50 mph. Northwest 15 to 30 mph. Gusts up to 45 mph decreasing to 35 mph after midnight. Southwest around 15 mph. Gusts up to 25 mph in the afternoon.
Expected snowfall: None in. None in. 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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