Avalanche Advisory: Monday - Jan 28, 2019

THIS AVALANCHE ADVISORY EXPIRED ON January 29, 2019 @ 6:12 am
Avalanche Advisory published on January 28, 2019 @ 6:12 am
Issued by Steve Mace - ESAC

LOW avalanche danger exists throughout the forecast area today at all elevations.  Natural and human trigger avalanches will be unlikely but not impossible.  With high temperatures expected today loose wet avalanches will be possible on solar aspects. Persistent slab avalanches will be unlikely and hard to trigger today but a resulting avalanche would likely have very high consequences.  Safe travel protocols are recommended.

1. Low

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Above Treeline
Generally safe avalanche conditions. Watch for unstable snow on isolated terrain features.

1. Low

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Near Treeline
Generally safe avalanche conditions. Watch for unstable snow on isolated terrain features.

1. Low

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Below Treeline
Generally safe avalanche conditions. Watch for unstable snow on isolated terrain features.
    Generally safe avalanche conditions. Watch for unstable snow on isolated terrain features.
Avalanche Problem 1: Persistent Slab
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While evidence suggests a healing trend there is still a remote possibility of triggering a large, destructive persistent slab avalanche.  Poor snowpack structure continues to be found throughout the forecast zone with loose faceted grains underlying a well-consolidated slab. This layer seems to be more reactive in places where the snowpack is thinner. 

In addition, buried surface hoar continues to be found in specific areas particularly at low and mid elevations in more sheltered locations.  Both of these layers are concerning. Forecaster confidence in the distribution and sensitivity of persistent slabs is low.  Do your own localized assessments and dig in to investigate these layers before committing to suspect terrain.

Avalanche Problem 2: Loose Wet
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Loose wet avalanches will be possible today.  This will be most concerning on E-SE-S aspects this morning particularly if the skies remain clear.  Increasing cloud cover predicted this afternoon would decrease the likelihood of loose wet activity. Wet snow surface and roller balls are signs of increasing hazard.  While resulting loose wet avalanches are likely to be small, they could be large enough to cause a fall or carry a skier through unpleasant terrain such as over cliffs or through confined couloirs.

advisory discussion

Our recent stint of spring-like conditions has largely been good for the health of our snowpack and observations continue to show a healing trend.  This does not mean that were entirely out of the woods, it's important to remember that LOW danger does not mean NO danger.  While the likelihood of triggering a persistent slab avalanche is low the consequence of a resulting slide would likely be catastrophic.  Even in times of relatively low danger, it's important to practice safe travel protocols such as limiting your exposure to one person at a time.

 

Weather and CURRENT CONDITIONS
weather summary

Warm, mild weather will continue today as we see increasing clouds and highs near 40° at upper elevations. Winds will be light out of the northeast.  Things cool off tonight as the temperature is expected to drop below freezing and the winds shift to the southwest

 

There is a chance of snow tomorrow as the high-pressure system breaks up and a weak low-pressure system moves through the area. 2-4 " is possible throughout the day with temperatures expected to be in the mid 30's at upper elevations. Winds will be light out of the southwest.  A more robust storm system seems to be moving into the area late Wednesday into Thursday that may bring higher snow totals for the area.

Two-Day Mountain Weather Forecast Produced in partnership with the Reno NWS
For 8,000 ft. to 10,000 ft.
Monday Monday Night Tuesday
Weather: Partly cloudy then becoming mostly cloudy. Mostly cloudy. Mostly cloudy. Chance of snow through the day. Snow levels 7000 feet increasing to 8000 feet in the afternoon. Chance of precipitation is 30%.
Temperatures: 40 to 48. deg. F. 26 to 31. deg. F. 38 to 46. deg. F.
Mid Slope Winds: Light winds becoming northeast 10 to 15 mph with gusts to 30 mph in the afternoon. Light winds. Gusts up to 25 mph after midnight. Southwest 10 to 15 mph in the morning becoming light. Gusts up to 30 mph.
Expected snowfall: None in. None in. 60% probability up to 1 inch. 40% probability 1 to 3 inches. | SWE = less than 0.10 inch. in.
Over 10,000 ft.
Monday Monday Night Tuesday
Weather: Partly cloudy then becoming mostly cloudy. Mostly cloudy. Mostly cloudy. Chance of snow through the day. Snow levels 8000 feet. Chance of precipitation is 40%.
Temperatures: 34 to 40. deg. F. 22 to 27. deg. F. 30 to 36. deg. F.
Ridge Top Winds: North 15 to 20 mph with gusts to 30 mph. Light winds becoming southwest 15 to 25 mph with gusts to 35 mph after midnight. Southwest 15 to 25 mph with gusts to 35 mph.
Expected snowfall: None in. None in. 60% probability up to 2 inches. 40% probability 2 to 4 inches. | SWE = up to 0.15 inch. 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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