Avalanche Advisory: Monday - Jan 6, 2020

THIS AVALANCHE ADVISORY EXPIRED ON January 7, 2020 @ 6:51 am
Avalanche Advisory published on January 6, 2020 @ 6:51 am
Issued by Chris Engelhardt - Eastern Sierra Avalanche Center

LOW avalanche danger exists at all Elevations on all Aspects. Loose Wet conditions on Southerly aspects should be given consideration, in addition to tracking for Stubborn Wind slab on isolated N-E terrain features.

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: Loose Wet
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With mild to relatively warm temperatures and light winds, loose wet conditions on sunny aspects should be considered for Monday. Although the sunny aspects have cooked down and consolidated a bit from their initial warm-up Jan 1st, southerly aspects should be assessed for small point release potential and particularly rock fall. The mid to lower elevations from tree line down will be of most concern.

Avalanche Problem 2: Wind Slab
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With mountains as big and complex as the High Sierra, one cannot discount the possibility of lingering stubborn wind slabs in isolated areas of complex terrain. Be particularly aware of unsupported slopes, convex rolls, or cross loaded terrain where a unique situation may have set up and is waiting for a trigger. The thin and spatially variable snowpack that currently exists has plenty of hard wind affected snow that may be residing on weak or slick sliding surfaces.

 

advisory discussion

Yesterday on steep, exposed, northeasterly terrain just at tree line (10,400ft), we found very firm, smooth wind board conditions. The main concern was “slide for life” hazard, as a fall would be difficult to arrest, and with the thin conditions, hitting obstacles was a real concern. A full complement of crampons, ice axe, and a rope is likely the needed kit for the serious adventurer right now who wants to access steep and technical terrain. We on the other hand, being near the end of multiple days of ski touring, decided to minimize our exposure and stick to inconsequential terrain. Mellow-angle sheltered terrain, in all reality, still has the most forgiving surface conditions.

There have been reports of significant spin drift in the high alpine environment in tight and channeled terrain. A party in the Big Pine area on Saturday experienced continuous stream-like sloughing of spindrift while they were climbing a steep couloir. Good reminder to always be aware and observant as strong to gale force winds in the high elevations can erode, strip and redistribute snow in dynamic ways.

Even with overall stable conditions, the snowpack is extremely variable both in depth and structure across the forecast zone, so every drainage and mountain should be looked at with a critical eye to assess what is really going on in your specific area.

 

Weather and CURRENT CONDITIONS
weather summary

A sunny day is on tap with mild temperatures and light westerly winds. Temperatures could reach the low 40sF below 10,000ft and from 31-36F at higher elevations. These quiet and mild conditions are expected to continue until Tuesday evening when a weak weather system moves through the area which could produce 2” for the mountains.  Potential for precipitation is also slated for the middle of the week and into next weekend, when a more “robust” winter storm will possibly hit the forecast zone.

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: Sunny. Snow levels below 7000 feet. Chance of precipitation is 0%. Clear. Snow levels below 7000 feet. Chance of precipitation is 0%. Sunny then becoming partly cloudy. Snow levels below 7000 feet. Chance of precipitation is 0%.
Temperatures: 37 to 42. deg. F. 12 to 17. deg. F. 38 to 44. deg. F.
Mid Slope Winds: Light winds. Light winds becoming southwest around 15 mph after midnight. Southwest around 15 mph. Gusts up to 25 mph increasing to 35 mph in the afternoon.
Expected snowfall: 0 in. 0 in. 0 in.
Over 10,000 ft.
Monday Monday Night Tuesday
Weather: Sunny. Snow levels below 7000 feet. Chance of precipitation is 0%. Clear. Snow levels below 7000 feet. Chance of precipitation is 0%. Sunny then becoming partly cloudy. Snow levels below 7000 feet. Chance of precipitation is 0%.
Temperatures: 31 to 36. deg. F. 12 to 17. deg. F. 32 to 38. deg. F.
Ridge Top Winds: West around 15 mph. Southwest around 15 mph. Southwest 15 to 30 mph. Gusts up to 25 mph increasing to 45 mph in the afternoon.
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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