THIS AVALANCHE FORECAST EXPIRED ON December 8, 2020 @ 6:55 am
Avalanche Forecast published on December 7, 2020 @ 6:55 am
Issued by Brandon Schwartz - Tahoe National Forest

Some minor amounts of drifting snow may occur today.  Small avalanches remain unlikely but are not impossible in isolated areas where drifting snow deposits. Regional scale LOW avalanche danger exists for all elevations.

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Above Treeline
Generally safe avalanche conditions. Watch for unstable snow on isolated terrain features.

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.
    Generally safe avalanche conditions. Watch for unstable snow on isolated terrain features.
Avalanche Problem 1: Normal Caution
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Ridgetop winds are gale force out of the E. The existing snowpack has already been through a few other similar E wind events so only minor amounts of blowing and drifting snow are expected today. Any areas where drifting snow is deposited will likely be too small to create problematic wind slabs. The exception could be encountered in chute/couloir/gully/cliff style terrain where a tiny wind slab that knocks you off your feet results in a tumble into the rocks. If you encounter blowing snow that is drifting into confined terrain, evaluate the downslope terrain hazards carefully. 

The more widespread hazard today is the shallow snowpack which has an increasing number of rocks, logs, and other obstacles emerging from or residing just below the snow surface. Slow down and travel with caution. It's looking like storms may return to the forecast area in a week or so, so don't get hurt now.

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* For the most part, a usable 1-2 foot deep supportable snowpack exists along the Sierra Crest above 7000' in the northern portion of the forecast area, above 8000' in the southern portion of the forecast area, and above 8600' in the Mt. Rose area. Variable snow surface conditions exist just about everywhere.

* Northerly aspects at and below treeline hold the most snow. The faceting process continues on these northerly aspects with clear skies, long nights, and low sun angles. Weak loose grain faceted snow is most apparent in the upper snowpack on wind protected NW-N-NE aspects. With the potential for storms on the horizon, this weak snow is becoming increasingly concerning.

* Expect wind scoured areas and/or bare ground in open near and above treeline terrain.

* Southerly aspects are a mix of bare ground and melt-freeze snow depending on wind protection.

Weather and CURRENT CONDITIONS
weather summary

Winds from the W for much of yesterday were below forecast speeds. Winds shifted to the NE and E around 2 pm yesterday afternoon and steadily increased to gale force during the overnight hours. Continued E wind ridgetop gusts to 100 mph are expected through this morning. Wind speeds are forecast to begin to gradually decrease this afternoon and tonight. High pressure builds tomorrow for lighter winds and warmer air temperatures. 

CONDITIONS ALONG THE SIERRA CREST BETWEEN 8200 FT. AND 9200 FT. IN THE LAST 24 HOURS
Weather Station Map
Weather Station Table
6am temperature: 17 to 24 deg. F.
Max. temperature: 36 to 41 deg. F.
Average ridgetop wind direction: SW shifting to E
Average ridgetop wind speed: SW 25 mph | E 53 mph
Maximum ridgetop wind gust: SW 40 mph | E 105 mph
New snowfall: 0 inches
Total snow depth: 14 to 17 inches
Two-Day Mountain Weather Forecast Produced in partnership with the Reno NWS
For 7000 ft. to 8000 ft.
Monday Monday Night Tuesday
Weather: Partly cloudy then becoming sunny. Snow levels below 7000 feet. Chance of precipitation is 5%. Clear. Snow levels below 7000 feet. Chance of precipitation is 0%. Sunny. Snow levels below 7000 feet. Chance of precipitation is 0%.
Temperatures: 35 to 40. deg. F. 20 to 28. deg. F. 47 to 52. deg. F.
Mid Slope Winds: East 15 to 25 mph with gusts to 45 mph. East around 15 mph with gusts to 35 mph in the evening becoming light. Light winds.
Expected snowfall: No accumulation. | SWE = none. No accumulation. | SWE = none. No accumulation. | SWE = none.
For 8000 ft. to 9000 ft.
Monday Monday Night Tuesday
Weather: Partly cloudy then becoming sunny. Snow levels below 7000 feet. Chance of precipitation is 5%. Clear. Snow levels below 7000 feet. Chance of precipitation is 0%. Sunny. Snow levels below 7000 feet. Chance of precipitation is 0%.
Temperatures: 32 to 37. deg. F. 21 to 27. deg. F. 45 to 50. deg. F.
Ridge Top Winds: East 40 to 60 mph with gusts to 100 mph. East 20 to 40 mph. Gusts to 75 mph decreasing to 55 mph after midnight. Southeast around 15 mph with gusts to 35 mph.
Expected snowfall: No accumulation. | SWE = none. No accumulation. | SWE = none. No accumulation. | SWE = none.
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