THIS AVALANCHE FORECAST EXPIRED ON February 8, 2019 @ 6:59 am
Avalanche Forecast published on February 7, 2019 @ 6:59 am
Issued by Andy Anderson - Tahoe National Forest - Sierra Avalanche Center

MODERATE avalanche danger exists in near and above treeline terrain due to some lingering wind slabs. The avalanche danger is LOW below treeline. Human-triggered avalanches may remain possible today.

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.

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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    Certain
    Very Likely
    Likely
    Possible
    Unlikely
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    Historic
    Very Large
    Large
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Wind slabs should have become more difficult to trigger in most places. However, some human-triggered wind slab avalanches may remain possible on specific terrain features in near and above treeline terrain on NW-N-NE-E-SE aspects. Steep complex terrain including couloirs/gullies, cliffy areas, unsupported slopes, and areas with convex slopes represent some places where finding an unstable wind slab may be possible. Some scouring and light wind transport may have occurred from last night's E-NE winds but any wind slabs formed by these short-lived winds should remain small and isolated. Large fragile cornices that could break far from their edges also exist above many wind-loaded slopes.

Cornices above a slope, wind drifts/pillows, ripples on the snow surface, and other wind created textures can offer clues to help identify where wind slabs may exist. Less wind-exposed and/or lower angle terrain should hold softer less variable snow.

recent observations

* Observations from the Blue Lakes area, Centerville Peak, Flagpole Peak, Blackwood Ridge, and Shirley Canyon all showed soft cold snow with no signs of instability in sheltered locations yesterday.

* Some active blowing snow was reported near the summit of Centerville Peak during the day and along Carson Pass yesterday afternoon.

* Small wind features on Blackwood Ridge and near Centerville Peak did not show signs of instability. 

* Observers reported large "tiger striping" and other signs of previous wind-loading on more exposed slopes in the Blue Lakes area.

Weather and CURRENT CONDITIONS
weather summary

The winds shifted to the E and NE along the ridgetops yesterday evening but remained mostly light to moderate in speed with a brief period between 10 pm and 2 am where they averaged ~20 mph. They calmed down earlier this morning and the forecast calls for light winds today. The weather should remain cold and calm today before some cloud cover starts to move into the area this afternoon and tonight. The winds should shift back to the SW and start to increase tonight ahead of a small storm approaching the area tomorrow evening. Another stronger storm should move into the region over the weekend. For more details check in with the Reno NWS.

Weather observations from along the Sierra Crest between 8200 ft. and 8800 ft.
0600 temperature: 8 to 16 deg. F.
Max. temperature in the last 24 hours: 16 to 20 deg. F.
Average wind direction during the last 24 hours: W shifting to E-NE yesterday evening
Average wind speed during the last 24 hours: W: 10 mph | E-NE: 10 to 20 mph
Maximum wind gust in the last 24 hours: 41 mph
New snowfall in the last 24 hours: 0 inches
Total snow depth: 97 to 115 inches
Two-Day Mountain Weather Forecast Produced in partnership with the Reno NWS
For 7000 ft. to 8000 ft.
Thursday Thursday Night Friday
Weather: Partly cloudy then becoming mostly cloudy. Snow levels below 7000 feet. Chance of precipitation is 0%. Mostly cloudy. Snow levels below 7000 feet. Chance of precipitation is 0%. Partly cloudy then becoming mostly cloudy. Chance of snow in the afternoon. Snow levels below 7000 feet. Chance of precipitation is 30%.
Temperatures: 25 to 30 deg. F. 7 to 17 deg. F. 25 to 30 deg. F.
Mid Slope Winds: Light winds. Light winds. South around 15 mph. Gusts up to 25 mph increasing to 35 mph in the afternoon.
Expected snowfall: No accumulation. | SWE = none. No accumulation. | SWE = none. 30% probability up to 1 inch. | SWE = trace amounts.
For 8000 ft. to 9000 ft.
Thursday Thursday Night Friday
Weather: Partly cloudy then becoming mostly cloudy. Snow levels below 7000 feet. Chance of precipitation is 0%. Mostly cloudy. Snow levels below 7000 feet. Chance of precipitation is 0%. Partly cloudy. Chance of snow in the afternoon. Snow levels below 7000 feet. Chance of precipitation is 25%.
Temperatures: 21 to 27 deg. F. 5 to 13 deg. F. 20 to 25 deg. F.
Ridge Top Winds: Light winds. Gusts up to 25 mph in the afternoon. Southwest 15 to 20 mph. Gusts up to 30 mph increasing to 45 mph after midnight. South 15 to 30 mph with gusts to 55 mph.
Expected snowfall: No accumulation. | SWE = none. No accumulation. | SWE = none. 30% probability up to 1 inch. | SWE = trace amounts.
Disclaimer

This avalanche forecast is provided through a partnership between the Tahoe National Forest and the Sierra Avalanche Center. This forecast 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 forecast applies only to backcountry areas outside established ski area boundaries. This forecast describes general avalanche conditions and local variations always occur. This forecast expires 24 hours after the posted time unless otherwise noted. The information in this forecast is provided by the USDA Forest Service who is solely responsible for its content.

For a recorded version of the avalanche forecast call (530) 587-3558 x258