Avalanche Advisory: Saturday - Feb 23, 2019

THIS AVALANCHE ADVISORY EXPIRED ON February 24, 2019 @ 6:41 am
Avalanche Advisory published on February 23, 2019 @ 6:41 am
Issued by Steve Mace - ESAC

MODERATE avalanche danger exists at upper elevations today while LOW danger exists for lower and mid elevations.  Sensitive wind slabs are the primary concern today, evaluate terrain features carefully and avoid areas with fresh wind deposit.

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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Calm and clear conditions made for an enjoyable day in the alpine yesterday with only isolated reports of snow moving around.  As winds increase today and shift to the west, expect to find new slab development on leeward slopes where terrain features encourage drifting.  Use surface clues such as blowing snow, drifting, and recent cornice growth to identify and avoid wind-loaded areas. While easterly aspects at upper elevations will be most concerning today, it will still be possible to find more stubborn slabs lingering on all aspects at upper and mid elevations.  Be particularly cautious in extreme terrain and on unsupported slopes where consequences of an avalanche are heightened.

Avalanche Problem 2: Loose Wet
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With increased temperatures and clear skies this morning there is a possibility of loose wet activity on solar aspects at lower elevations. The risk will increase if the forecasted cloud cover does not materialize this afternoon.  Watch for signs of decreasing stability such as wet snow surface and rollerball activity.

advisory discussion

While wind slabs remain our primary concern today it is important to keep in mind the rain crust from February 14/15.  This crust has been confirmed above 10000’ and can be found on the surface in many areas. If you see this shiny reflective surface be cautious, as a fall on this crust could lead to slide for life situation. Also, it is proving to make a good bed surface for loose sloughs or larger slab avalanches.  Keep this in mind if you decide to travel into more committing terrain today.

The beacon park is up and running at Mammoth Mountain! Swing by if you are looking to brush up on your companion rescue skills. Be safe and enjoy the weekend.

recent observations
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2/22- Bishop area, Sensitive wind slabs on Mt Tom

2/22-June Lake area, Stable conditions in the negatives

2/22-Mammoth Area, Wind Slabs in the Red Cone area

2/22- June Lake area, Reversed peak snow conditions 

2/21-June Lake Area, Ice Crusts on the Chicken Wing

2/19- June Lake area, Skier triggered Avalanche 3D chute

Weather and CURRENT CONDITIONS
weather summary

Today you can expect to see sunny skies becoming partly cloudy in the afternoon. Highs are expected in the mid-20s at upper elevations. Winds will be moderate out of the west with gusts of 30 mph expected at ridge tops.

Mostly cloudy skies are on tap for tomorrow as a low-pressure system enters the area. Winds will increase slightly and shift to a more southerly direction, and temperatures will be in the low to mid-20s. There is a slight chance of snow showers developing in the evening hours, though Monday is looking more promising.

Two-Day Mountain Weather Forecast Produced in partnership with the Reno NWS
For 8,000 ft. to 10,000 ft.
Saturday Saturday Night Sunday
Weather: Sunny then becoming partly cloudy. Mostly cloudy. Snow levels below 7000 feet. Mostly cloudy. Slight chance of snow.
Temperatures: 27 to 35. deg. F. 15 to 20. deg. F. 29 to 37. deg. F.
Mid Slope Winds: West around 15 mph with gusts to 30 mph. Southwest 15 to 20 mph with gusts to 40 mph. Southwest 15 to 20 mph with gusts to 45 mph.
Expected snowfall: None in. None in. None in.
Over 10,000 ft.
Saturday Saturday Night Sunday
Weather: Sunny then becoming partly cloudy. Mostly cloudy. Snow levels below 7000 feet. Mostly cloudy. Slight chance of snow.
Temperatures: 19 to 24. deg. F. 11 to 16. deg. F. 20 to 26. deg. F.
Ridge Top Winds: West 15 to 20 mph with gusts to 30 mph. Southwest 15 to 30 mph with gusts to 45 mph. Southwest 20 to 30 mph with gusts to 45 mph.
Expected snowfall: None in. None in. None 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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