Avalanche Advisory: Wednesday - Mar 4, 2020 | Eastern Sierra Avalanche Center

THIS AVALANCHE ADVISORY EXPIRED ON March 5, 2020 @ 6:39 am
Avalanche Advisory published on March 4, 2020 @ 6:39 am

Issued by Steve Mace - ESAC

Bottom Line

MODERATE avalanche danger exists at mid and upper elevations today and LOW avalanche danger resides at lower elevations. Unseasonably warm temperatures, sunny skies, and light winds are expected today and may lead to substantial surface warming on solar aspects. Expect loose wet avalanches to be possible at all elevations today. While less concerning, wind slabs deposited during and immediately after Saturday’s storm deserve extra consideration on all aspects at mid and upper elevations. Evaluate snow and terrain carefully if you head into the backcountry today and avoid features of concern.

2. Moderate

Above Treeline

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

2. Moderate

Near Treeline

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

1. Low

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: Loose Wet

Type ?
Aspect/Elevation ?
Likelihood ?

Certain

Very Likely

Likely

Possible

Unlikely
Size ?

Historic

Very Large

Large

Small

Cold temperatures and clear skies were conducive to a strong overnight freeze, but sunny skies and very warm daytime temperatures are expected today. This will likely lead to substantial surface warming on solar aspects at all elevations. Sizable loose wet avalanches will be possible today. Expect loose wet hazard to spike first on easterly slopes transitioning to southerly and westerly slopes by the afternoon. Wet, sticky snow surface, rollerballs, and pinwheels are all signs of surface warming and may foreshadow larger point release avalanches. Be aware of hazards that may exist above you and be particularly cautious around terrain features that increase the consequences of an avalanche such as cliff bands, creek beds, or gully features.

Avalanche Problem 2: Wind Slab

Type ?
Aspect/Elevation ?
Likelihood ?

Certain

Very Likely

Likely

Possible

Unlikely
Size ?

Historic

Very Large

Large

Small

While light winds will limit the potential for new slab development today, stubborn wind slabs on all aspects remain a hazard. Variable winds have led to erratic loading patterns leaving many typical start zones stripped bare and large deposits in less typical areas. Isolated areas of wind slab may exist on specific terrain features below treeline and further down slopes than you may typically expect to find them. While natural activity will be unlikely, wind slabs deposited over the weekend may still be reactive to human triggers. Exposed leeward catchment zones, convex and unsupported slopes, and cross-loaded gully features near and above treeline deserve elevated caution. Large drifts, recent cornice growth, and uneven snow surfaces are all clues that indicate nearby wind deposits. Do your own localized assessments and be suspect of terrain features that encourage drifting.

advisory discussion

While a healthy dose of fresh precipitation has improved riding conditions and led to a period of elevated avalanche concerns, it is prudent to remember that we are still dealing with a thin snowpack. Keep in mind that before this most recent storm contiguous panels of snow were few and far between. This is particularly true on solar aspects and at lower elevations. Realize that this fresh snow will be hiding many obstacles just below the surface. Be on the lookout for shallowly buried rocks and trees and move cautiously through the terrain.

recent observations

Submit Snowpack Observations

Submit Avalanche Observations

03/03- June Lake- Surface warming on solar aspects

03/03-Mammoth Area- Snow conditions in the Lakes Basin

03/03- Mammoth Area- surface warming and isolated areas of wind deposit on the backside of Mammoth mountain

03/02- Mammoth Area- Surface instabilities in the Lakes Basin

03/02- Northern June Lake- Snow conditions Mt Gibbs

03/02-Independence- Snow conditions in Onion valley

Weather and CURRENT CONDITIONS

weather summary

High pressure will remain in control bringing clear skies, light winds, and temperatures above seasonal averages today. Day time highs are likely to reach over 50°F at mid-elevations today while temperatures may reach the mid 40°s in the alpine.

We can expect the winds to increase tomorrow with thickening cloud cover as a weak low-pressure system approaches the area. This system may bring light precipitation to the area this weekend.

Two-Day Mountain Weather Forecast Produced in partnership with the Reno NWS

For 8,000 ft. to 10,000 ft.

	Wednesday	Wednesday Night	Thursday
Weather:	Sunny.	Clear.	Sunny.
Temperatures:	44 to 54. deg. F.	24 to 30. deg. F.	45 to 55. deg. F.
Mid Slope Winds:	Light winds.	Light winds becoming southwest around 15 mph with gusts to 35 mph after midnight.	Southwest around 15 mph with gusts to 40 mph.
Expected snowfall:	0 in.	0 in.	0 in.

Over 10,000 ft.

	Wednesday	Wednesday Night	Thursday
Weather:	Sunny.	Clear.	Sunny then becoming partly cloudy.
Temperatures:	35 to 43. deg. F.	21 to 27. deg. F.	35 to 43. deg. F.
Ridge Top Winds:	Light winds.	Light winds becoming southwest around 15 mph with gusts to 35 mph after midnight.	Southwest 15 to 20 mph with gusts to 40 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.