Avalanche Advisory: Friday - Mar 8, 2019

THIS AVALANCHE ADVISORY EXPIRED ON March 9, 2019 @ 6:10 am
Avalanche Advisory published on March 8, 2019 @ 6:10 am
Issued by Chris Engelhardt - Eastern Sierra Avalanche Center

The avalanche danger is MODERATE at Upper elevations and LOW at Middle and Lower elevations. Southerly winds transporting recent storm snow will produce WIND SLAB on leeward Northerly-Easterly aspects. Be particularly aware in steep and confined terrain.

2. Moderate

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

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.
    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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Leeward NORTHERLY-EASTERLY slopes will be of most concern as Southerly winds persist across the range. Intricate and extreme terrain will be most likely to load with wind transported snow. Wind velocities will be at that perfect transporting speed of 15-30mph across all elevation bands to deposit available snow on leeward slopes. Be cognizant of active wind loading and fresh looking snow deposits on terrain you are travelling upon. Remember that across the zone, the snowpack below 10000’ has the February 14th rain crust which has proven to be a slick bed surface for a few skier triggered avalanches. Probing the snow can give you an indication of how deep this layer resides in your area.

 

Avalanche Problem 2: Cornice
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The recent storm's moist snow is particularly conducive to building cornices adjacent to ridgelines and bordering potential ski objectives. Be on the lookout for cornices primarily on EASTERLY and NORTHERLY aspects throughout the range. Give these curling wavelike features a wide berth and make sure you are well on terra firma on the windward side of ridges. Cornice fall is not only hazardous if it gives way beneath you, but can affect travelers on slopes below. Cornice fall can be the big trigger that starts avalanches on slopes below as the falling blocks can be of tremendous weight and scale. Cold temps and forecasted cloudy skies should keep these relatively locked up today, but if sunnier conditions prevail, be aware that solar gain could contribute to loosening freshly formed cornices.

advisory discussion

PUBLIC OBSERVERS/SKIERS/RIDERS: If you are out and about please submit your pertinent observations from your backcountry travels. It takes a community to help disseminate snowpack information across this big Mountain Range and Forecast Zone. Thanks to all who participated and joined us for our three avalanche awarness nights in Mammoth, June Lk and most recently Bishop last night. It was a great time seeing everybody and talking shop on everything avalanche and snow related.

Much THANKS--

ESAC Forecasters

Weather and CURRENT CONDITIONS
weather summary

Much colder temperatures are expected today with mostly cloudy to partly cloudy skies. The south end of the forecast zone may see sunnier conditions. SW winds are slated to blow at moderate speeds in the 15-25mph range with slightly stronger velocities and locally higher gusts up to 50mph at ridge tops. A slight chance of snow with up to 1” may fall, particularly in the Mammoth area. Temperatures will be above freezing (21-31F) in the lower elevations while high elevations will be in the 14-20F range today.  

 

Two-Day Mountain Weather Forecast Produced in partnership with the Reno NWS
For 8,000 ft. to 10,000 ft.
Friday Friday Night Saturday
Weather: Mostly cloudy then becoming partly cloudy. Chance of snow showers through the day. Snow levels below 7000 feet. Chance of precipitation is 30%. Partly cloudy. Snow levels below 7000 feet. Chance of precipitation is 5%. Partly cloudy then becoming mostly cloudy. Slight chance of snow showers in the afternoon. Snow levels below 7000 feet. Chance of precipitation is 10%.
Temperatures: 21 to 31. deg. F. 8 to 14. deg. F. 23 to 31. deg. F.
Mid Slope Winds: Southwest 15 to 25 mph with gusts to 55 mph. Southwest 15 to 20 mph with gusts to 40 mph. Southwest around 15 mph with gusts to 30 mph.
Expected snowfall: 90% probability up to 1 inch. 10% probability of 1 to 3 inches. | SWE = less than 0.10 inch. in. No accumulation. | SWE = none. in. No accumulation. | SWE = none. in.
Over 10,000 ft.
Friday Friday Night Saturday
Weather: Mostly cloudy. Chance of snow showers. Snow levels below 7000 feet. Chance of precipitation is 40%. Partly cloudy. Snow levels below 7000 feet. Chance of precipitation is 10%. Partly cloudy then becoming mostly cloudy. Slight chance of snow showers in the afternoon. Snow levels below 7000 feet. Chance of precipitation is 15%.
Temperatures: 14 to 20. deg. F. 3 to 8. deg. F. 15 to 21. deg. F.
Ridge Top Winds: Southwest 20 to 30 mph. Gusts up to 55 mph decreasing to 45 mph in the afternoon. Southwest 15 to 30 mph with gusts to 40 mph. Southwest 15 to 25 mph with gusts to 40 mph.
Expected snowfall: 90% probability up to 1 inch. 10% probability of 1 to 2 inches. | SWE = less than 0.10 inch. in. No accumulation. | SWE = none. in. No accumulation. | SWE = trace amounts. 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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