Avalanche Advisory: Tuesday - Mar 31, 2020

THIS AVALANCHE ADVISORY EXPIRED ON April 1, 2020 @ 7:00 am
Avalanche Advisory published on March 31, 2020 @ 7:00 am
Issued by Josh Feinberg - Eastern Sierra Avalanche Center

Significant SW winds will continue thru today with gusts up to 65mph over ridge tops.  Many wind slab avalanches were triggered yesterday due to wind loading, and conditions today should be no different with continued avalanche danger on the higher end of MODERATE above, at, and slightly below treeline. Triggering avalanches today in wind loaded areas just below ridge lines, sidewalls of gullies, and steep mid-slope catchment areas will be no surprise, and could lead to injury or worse.

          

*Given the current situation, an injury at this time requiring medical attention could result in serious consequences for yourself and others. Tone it down, limit your risks! 

 

*Keep at least 6ft of physical distance from others at all times … no car-pooling, no sharing snacks!    

 

*Be respectful of one another, ski one at a time and don’t drop in on top of others.  

 

*To comply with the Inyo County Sheriff’s office request, ESAC’s forecasts and field work is now limited to Mono County.

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.

2. Moderate

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Below Treeline
Heightened avalanche conditions on specific terrain features. Evaluate snow and terrain carefully; identify features of concern.
    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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SW have been blowing since two nights ago, and are expected to continue thru today with gusts up to 65mph over ridgetops.  Watch for denser deposits of snow sensitive to human triggering just below ridgelines, sidewalls of gullies, steep convexities, and around cross-slope depressions and rock outcrops on NW-N-E-SE facing slopes at tree-line, above tree-line, and slightly below.  A slab could surprise you and have especially bad consequences if triggered while climbing up from below.  Blowing snow, cornices and textured snow can help you figure out where these slabs may lie, and shooting cracks mean that you are already on one.  Be aware of what could funnel down onto you from above in extreme terrain as wind and sun today will keep things dynamic,  An avalanche today could sweep you thru trees and result in injury or worse especially on a slope over a cliff band or gully/depression.   

 
Avalanche Problem 2: Loose Dry
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Significant loose dry sloughing occurred yesterday in steep confined sheltered north facing slopes at mid elevations.  Watch for this potential today at mid and upper elevations.  If not managed well, slough could sweep you off your feet into undesirable terrain, and even end in a burial.

 
Avalanche Problem 3: Loose Wet
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Loose wet avalanches could become a concern today as steep E-S-W facing slopes warm from sun exposure if the winds die down and do not keep them cool.  Watch for small rollerballs as early indications that a larger loose wet slide may be possible. Avoid steep slopes that are becoming wet and manky, and be aware of what could come down on you from above. 

 
 
advisory discussion

Cornices have been growing.  Be cautious of getting too close to the edge, and as satisfying as it can be to stomp on them, be aware of how knocking off a large chunk or triggering a potential windslab may effect people below you. Especially with the amount of people in the backcountry right now it is more important than ever to think about others.  Keep your distance, ski one at a time, don’t drop in on each other.  Carry the right gear - beacon / shovel / probe is still the minimum standard.  

 

If you are choosing to go out despite the requests to avoid the backcountry, slow it down and keep it mellow.  A shallow snowpack with plenty of obstacles means a potential for injury exists for everyone.

 
recent observations
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-3/30 - Mammoth - Sherwins: Skier triggered windslab.

-3/30 - Mammoth Lakes Basin - Red Cone Area: Intentionally triggered windslabs, loose dry sloughing.

-3/30 - VA Lakes: Natural avalanche activity.

-3/29 - Mammoth - Sherwins:  Avalanche activity.

Weather and CURRENT CONDITIONS
weather summary

A Mild and sunny day is on tap for today with southwest winds gusting up to 65mph over ridges, decreasing in the afternoon. Expect high temperatures to reach 40°F around 10,000’.  

 

Temperatures will cool off thru the remainder of the week, with unsettled weather and chances of snow returning for the weekend into next week. 

Two-Day Mountain Weather Forecast Produced in partnership with the Reno NWS
For 8,000 ft. to 10,000 ft.
Tuesday Tuesday Night Wednesday
Weather: Sunny. Snow levels 7500 feet increasing to 8500 feet in the afternoon. Chance of precipitation is 0%. Clear. Snow levels 7500 feet decreasing to below 7000 feet after midnight. Chance of precipitation is 0%. Sunny. Snow levels below 7000 feet. Chance of precipitation is 0%.
Temperatures: 41 to 51. deg. F. 24 to 30. deg. F. 38 to 48. deg. F.
Mid Slope Winds: Southwest 15 to 20 mph with gusts to 40 mph. Southwest around 15 mph with gusts to 35 mph. Southwest 15 to 20 mph. Gusts up to 45 mph.
Expected snowfall: 0 in. 0 in. 0 in.
Over 10,000 ft.
Tuesday Tuesday Night Wednesday
Weather: Sunny. Snow levels 7500 feet increasing to 8500 feet in the afternoon. Chance of precipitation is 0%. Clear. Snow levels 7000 feet decreasing to below 7000 feet after midnight. Chance of precipitation is 0%. Sunny. Snow levels below 7000 feet. Chance of precipitation is 0%.
Temperatures: 33 to 41. deg. F. 18 to 24. deg. F. 29 to 37. deg. F.
Ridge Top Winds: Southwest 30 to 45 mph decreasing to 25 to 35 mph in the afternoon. Gusts up to 65 mph. Southwest 25 to 40 mph with gusts to 65 mph. Southwest 30 to 50 mph with gusts to 70 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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