THIS AVALANCHE FORECAST EXPIRED ON April 15, 2018 @ 6:49 am
Avalanche Forecast published on April 14, 2018 @ 6:49 am
Issued by Brandon Schwartz - Tahoe National Forest

MODERATE avalanche danger will exist at all elevations today as a loose wet avalanche problem develops in response to daytime warming. Monitor snow surface conditions and avoid travel in or below avalanche terrain in areas where the snow surface is marginally supportable to unsupportable, where human triggered roller balls are occurring, or where loose wet avalanches are actively occurring.

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: Loose Wet
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A decent snow surface refreeze is expected to have occurred last night from radiational cooling under clear skies. This is despite at or above freezing air temperatures last night in most locations. Rapid warming conditions and well above freezing air temperatures today will lead to another round of loose wet avalanche problems that develop as the day progresses. Loose wet avalanches will be possible today on all aspects at all elevations. Avalanche size up to D2 is possible (large enough to bury or injure a person).

Mid and upper elevation NW-N-NE aspects may see human triggered roller balls as an indication of potential unstable conditions as the recent storm snow continues to transition to corn. Where melt-freeze conditions are more established on E-SE-S-SW-W aspects, focus on monitoring snow surface supportability. Once the snow surface is in melt phase and conditions become marginally supportable to unsupportable, avoid travel in or below avalanche terrain.

recent observations
Submit Observations

* Observations were made yesterday on Maggie's Peak South (Desolation Wilderness Area). Warming conditions and snow surface melt were observed in this area on all aspects. Recent storm snow on E-SE-S-SW-W aspects in the 7,500' to 8,500' elevation range was mostly assimilated with the older melt-freeze snow below. Loose wet avalanche problems had developed by the early afternoon hours, especially on the more northerly aspects above 7,500' where the recent storm snow was entering into melt phase for the first time.

* The high sun angle this time of year is allowing for significant amounts of incoming solar radiation on NW-N-NE aspect terrain that is otherwise well shaded from November through February.

* Snow cover below 7,200' to 7,500' is becoming very thin to nonexistent in many portions of the forecast area. There are a few areas of exception.

Weather and CURRENT CONDITIONS
weather summary

Short lived high pressure will last through today before breaking down tomorrow ahead of an approaching storm system that is expected to arrive tomorrow evening. Sunny skies today will give way to increasing cloud cover tonight and tomorrow. Ridgetop winds shifted from NE to SW around midnight. Light to moderate speed SW winds are expected today. Winds are forecast to increase to moderate speed tonight and become strong tomorrow. For the latest on the approaching storm system, check the Winter Weather Statement from NWS Reno.

CONDITIONS ALONG THE SIERRA CREST BETWEEN 8200 FT. AND 9200 FT. IN THE LAST 24 HOURS
Weather Station Map
Weather Station Table
6am temperature: 30 to 38 deg. F.
Max. temperature: 43 to 47 deg. F.
Average ridgetop wind direction: NE shifting to SW
Average ridgetop wind speed: NE 30 mph | SW 19 mph
Maximum ridgetop wind gust: NE 53 mph | SW 30 mph
New snowfall: 0 inches
Total snow depth: 51 to 90 inches
Two-Day Mountain Weather Forecast Produced in partnership with the Reno NWS
For 7000 ft. to 8000 ft.
Saturday Saturday Night Sunday
Weather: Sunny skies. Partly cloudy skies, becoming mostly cloudy. Partly cloudy skies. A slight chance of rain and snow in the afternoon. Snow level 7,000'.
Temperatures: 50 to 56 deg. F. 31 to 36 deg. F. 46 to 52 deg. F.
Mid Slope Winds: SW SW SW
Wind Speed: Light winds, becoming 10 to 15 mph with gusts to 25 mph in the afternoon. 10 to 15 mph with gusts to 40 mph. 15 to 25 mph with gusts to 45 mph, increasing to 25 to 35 mph with gusts to 65 mph in the afternoon.
Expected snowfall: 0 0 0 to trace
For 8000 ft. to 9000 ft.
Saturday Saturday Night Sunday
Weather: Sunny skies. Partly cloudy skies, becoming mostly cloudy. Partly cloudy skies. A slight chance of snow in the afternoon.
Temperatures: 46 to 52 deg. F. 28 to 33 deg. F. 40 to 46 deg. F.
Ridge Top Winds: SW SW SW
Wind Speed: 10 to 15 mph with gusts to 30 mph. 20 to 30 mph. Gusts to 40 mph increasing to 60 mph after midnight. 25 to 35 mph with gusts to 70 mph, increasing to 30 to 50 mph with gusts to 80 mph in the afternoon.
Expected snowfall: 0 0 0 to trace
Disclaimer

This avalanche advisory is provided through a partnership between the Tahoe National Forest and the Sierra Avalanche Center. This advisory covers the Central Sierra Nevada Mountains between Yuba Pass on the north and Ebbetts Pass on the south. Click here for a map of the forecast area. This advisory applies only to backcountry areas outside established ski area boundaries. This advisory describes general avalanche conditions and local variations always occur. This advisory expires 24 hours after the posted time unless otherwise noted. The information in this advisory is provided by the USDA Forest Service who is solely responsible for its content.

For a recorded version of the Avalanche Advisory call (530) 587-3558 x258