THIS AVALANCHE ADVISORY EXPIRED ON April 1, 2017 @ 7:01 am
Avalanche Advisory published on March 31, 2017 @ 7:01 am
Issued by Andy Anderson - Tahoe National Forest

In most areas along the Sierra Crest, the avalanche danger will remain LOW today due to cooler temperatures, cold NE winds, and a lack of significant new snow accumulation. Across the Lake in the Mt. Rose area and in other high-elevation areas across the region where more snow fell, areas of MODERATE avalanche danger will exist in near and above treeline terrain where wind slabs may exist. If more warming occurs today than forecasted, some loose wet instabilities may form. 

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: Wind Slab
  • Type ?
  • Aspect/Elevation ?
  • Likelihood ?
    Certain
    Very Likely
    Likely
    Possible
    Unlikely
  • Size ?
    Historic
    Very Large
    Large
    Small

In the Mt. Rose area and in other isolated high-elevation areas across the region where the most snow accumulated during the storm, some human triggered wind slabs may remain possible today. Most of these should remain small and not extend very far away from the ridgelines, but a few larger wind slabs could exist in isolated areas where the most snow fell. The wind slabs will most likely exist where the NE winds have wind-loaded W-SW-S aspects and cross-loaded NW and SE aspects in near and above treeline terrain. Sun on these aspects this afternoon could also weaken the wind slabs. Along the Sierra Crest where less than 3 inches of new snow accumulated, wind slabs should remain too small to represent a significant avalanche problem due to the minimal amounts of new snow. 

The cooler temperatures, continued cloud cover, and cold NE winds should prevent loose wet instabilities from becoming widespread. If more warming occurs than forecasted today, loose wet instabilities could form on slopes where new snow exists. 

recent observations

Yesterday observations on the far east ridge of Tamarack Peak found 4 to 5 inches of new snow and wind slabs up to 8 inches in depth. Ski kicks produced cracking and some small wind slab failures on test slopes in this area. Across the Lake on Andesite Ridge less than an inch of new snow existed. This dusting of new snow rested on top of a breakable rain crust above a few feet of wet unsupportable snow. This crust was quickly refreezing. Observations revealed no signs of instability in this area. In both places strong to gale force winds scoured slopes and transported snow all day exposing firm icy surfaces and creating some wind slabs in the Mt. Rose area. 

Weather and CURRENT CONDITIONS
weather summary

Storm totals along the Sierra Crest range from less than an inch to up to 3 inches in some areas. In the Mt. Rose area, 4 to 6 inches of snow accumulated since Wed. night. Some light and isolated snow showers may continue this morning in the mountains especially in the southern part of the forecast area. The widespread cloud cover over the forecast area should start to dissipate today with sunny skies expected by this afternoon. The northeast winds will continue today and temperatures should remain in the 30's above 7000 ft. with a few areas warming to 40 degrees. Skies should remain clear overnight and tomorrow and the northeast and east winds should start to decrease. The forecast calls for a sunny and much warmer day tomorrow with daytime highs climbing into the mid to upper 40's above 7000 ft.

Weather observations from along the Sierra Crest between 8200 ft. and 8800 ft.
0600 temperature: 17 to 21 deg. F.
Max. temperature in the last 24 hours: 33 to 36 deg. F.
Average wind direction during the last 24 hours: Southwest shifting to northeast yesterday around noon
Average wind speed during the last 24 hours: 30 to 40 mph
Maximum wind gust in the last 24 hours: 96 mph
New snowfall in the last 24 hours: 1 to 3 inches
Total snow depth: 121 to 176 inches
Two-Day Mountain Weather Forecast Produced in partnership with the Reno NWS
For 7000 ft. to 8000 ft.
Friday Friday Night Saturday
Weather: Mostly cloudy with isolated snow showers in the morning, becoming sunny in the afternoon. Clear Sunny
Temperatures: 35 to 40 deg. F. 20 to 25 deg. F. 43 to 48 deg. F.
Wind Direction: Northeast Northeast East
Wind Speed: 15 to 25 mph with gusts to 45 mph 15 to 20 mph with gusts to 45 mph 10 to 15 mph with gusts to 30 mph
Expected snowfall: up to 1 in. 0 in. 0 in.
For 8000 ft. to 9000 ft.
Friday Friday Night Saturday
Weather: Mostly cloudy with isolated snow showers in the morning, becoming sunny in the afternoon. Clear Sunny
Temperatures: 30 to 35 deg. F. 20 to 25 deg. F. 40 to 45 deg. F.
Wind Direction: Northeast Northeast East
Wind Speed: 30 to 50 mph with gusts to 85 mph 20 to 35 mph with gusts to 70 mph 15 to 25 mph with gusts to 60 mph decreasing to 40 mph in the afternoon
Expected snowfall: up to 1 in. 0 in. 0 in.
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