Avalanche Advisory: Sunday - Apr 7, 2019

THIS AVALANCHE ADVISORY EXPIRED ON April 9, 2019 @ 6:43 am
Avalanche Advisory published on April 7, 2019 @ 6:43 am
Issued by Steve Mace - ESAC

*This Avalanche Advisory is in effect for April 7-8 *

Heightened avalanche conditions exist throughout the forecast area. Expect daytime warming to increase the risk of Loose Wet avalanches at all elevations.  There also remains the possibility of finding small wind slabs on specific terrain features at mid and upper elevations. Evaluate snow conditions and terrain carefully and avoid features of concern.

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Avalanche Problem 1: Loose Wet
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Warm temperatures and the absence of a strong overnight freeze will increase the risk of loose wet avalanches today and tomorrow.  While partly cloudy skies will limit solar gain they will also aid in a strong greenhousing effect, increasing the air temperature as solar radiation is trapped underneath overlying clouds.  While solar aspects will become more concerning if the sun comes out, you can expect loose wet avalanches to be possible on all aspects and at all elevations. Increasing boot penetration, wet, sticky snow surfaces, and rollerballs are all signs of surface warming and may foreshadow larger point release avalanches.  Expect lower elevations to be of greater concern than alpine terrain and be prepared for the danger to be low in the morning, rising throughout the day as the ambient air temperature increases.

Avalanche Problem 2: Wind Slab
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While only small amounts of snow fell with our last storm, strong SW winds have done their part to transport loose snow to leeward slopes. There remains a possibility of finding small wind slabs on northerly and easterly terrain at mid and upper elevations. While resulting avalanches are likely to be small and may not pose a significant hazard to backcountry travelers there is certainly enough snow to take you off your feet or carry you though unpleasant terrain.  Problem areas will be specific to terrain features that encourage drifting such as the leeward sides of ridgelines, gully features, and cross-loaded depressions. Be particularly cautious in extreme terrain or on steep unsupported slopes where the consequences of an avalanche are elevated.  Surface clues such as blowing snow, recent cornice growth and uneven snow surfaces can help to identify and avoid areas of recent wind deposit.  Expect the sensitivity of wind slab avalanches to diminish over the next couple days as wind speeds drop slightly and loose snow available for transport becomes harder to find.

Avalanche Problem 3: Cornice
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As temperatures rise over the next couple of days it is possible that large cornice features will become more sensitive. Cornices can be unpredictable and deadly.  Give these large, wave-like structures a wide birth and be cautious of the overhead hazard they pose. Limit your exposure by making sure you are standing on firm ground and avoid traveling underneath large cornice features. 

advisory discussion

Monitoring warming will be crucial over the next couple of days. As frozen surface crusts become soft throughout the day, keeping track of increasing boot penetration can be a useful tool. Starting early and making sure you’re off suspect slopes before the afternoon heats up is advised.  Stay safe and enjoy the warm weather, it looks like we may be in for a brief return to winter on the east side later this week. 

Weather and CURRENT CONDITIONS
weather summary

 Expect mostly cloudy skies and warm temperatures to persist over the next couple of days.  Daytime highs are expected in the mid 40’s at upper elevations.  The winds will shift to the west today as wind speeds drop slightly; expect gusts to reach 45mph on ridge tops.   Things will cool off slightly this evening though it does not look like we will see a hard freeze tonight with lows expected to remain close to freezing at upper elevations, and well above freezing at lower elevations. 

Tomorrow promises to bring very similar weather marked by increasing cloud cover, warm temperatures, and moderate SW winds. There is a slight chance of showers on Monday evening preceding an approaching low-pressure cold front. Expect to see cold temperatures return on Tuesday with increased chances of precipitation and strong winds.

Two-Day Mountain Weather Forecast Produced in partnership with the Reno NWS
For 8,000 ft. to 10,000 ft.
Sunday Sunday Night Monday
Weather: Mostly cloudy then becoming partly cloudy. Mostly cloudy. Mostly cloudy.
Temperatures: 45 to 55. deg. F. 30 to 36. deg. F. 46 to 56. deg. F.
Mid Slope Winds: Southwest 10 to 20 mph with gusts to 35 mph. Southwest around 15 mph with gusts to 35 mph. Southwest 15 to 25 mph. Gusts up to 40 mph.
Expected snowfall: 0 in. 0 in. 0 in.
Over 10,000 ft.
Sunday Sunday Night Monday
Weather: Mostly cloudy then becoming partly cloudy. Mostly cloudy. Partly cloudy then becoming mostly cloudy.
Temperatures: 36 to 44. deg. F. 28 to 34. deg. F. 35 to 45. deg. F.
Ridge Top Winds: West 20 to 35 mph with gusts to 45 mph. West 15 to 25 mph. Gusts up to 45 mph. Southwest 20 to 30 mph with gusts to 50 mph.
Expected snowfall: 0 in. 0 in. 0 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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