THIS AVALANCHE FORECAST EXPIRED ON April 13, 2020 @ 7:00 am
Avalanche Forecast published on April 12, 2020 @ 7:00 am
Issued by Andy Anderson - Tahoe National Forest - Sierra Avalanche Center

Cooler weather and some cloud cover should make avalanche activity unlikely this morning. In areas that see sunshine or rain on snow this afternoon, some loose wet avalanches may become possible. The avalanche danger is LOW this morning and may increase to MODERATE this afternoon below 8000 ft. 

1. Low

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

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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    Certain
    Very Likely
    Likely
    Possible
    Unlikely
  • Size ?
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    Very Large
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Last night's refreeze was either weak or non-existent in most places due to partly cloudy skies and near or above freezing temperatures. While cooler weather and some cloud cover should work to limit the amount of wet snow that forms today, it will not take much warming to melt through the thin surface crust and expose wet snow leftover from yesterday. By this afternoon the weather forecast provides two possible ways for this warming to happen: periods of sunshine in some areas or light rain showers below 8000 ft in other areas. If either of these things happens, it may be possible for some loose wet avalanches to occur on steep sunny slopes or on slopes where rain falls on the snow. Above 8000 ft. loose avalanche activity should remain unlikely. 

Expect variable conditions including wet snow, firm surfaces breakable crusts, and scoured surfaces in the backcountry today. These conditions could change quickly with either sun or rain, so stay alert and remain flexible with your travel plans. Avalanches do not represent the only hazards and these variable conditions could present other travel challenges. 

recent observations
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Observers reported a weak refreeze on Red Lake Peak, Echo Peak, and Relay Peak yesterday. Ankle to skin-deep wet snow and natural and human-triggered roller balls and pinwheels started to occur between 9 and 10 am in these areas.  

A larger loose wet avalanche had occurred recently (likely April 10) in the NE bowl of Angora Peak.

Snowpit tests near the slab avalanche on Relay Peak from April 8 did not show any lingering signs of instability. 

Variable snow conditions ranging from punchy to warm and wet to breakable crusts to wind-scoured surfaces existed in the backcountry. 

Weather and CURRENT CONDITIONS
weather summary

Temperatures remained above freezing in most places last night with only a few sensors above 8500 ft. showing at or near freezing overnight lows. Some cloud cover has started to move into the region and the winds have shifted back to the NE as a weak cold front approaches the area. This front should bring a few more clouds to the area today especially in the morning. By the afternoon a mix of clouds and sun should prevail over the region. Some of these afternoon clouds may produce light precipitation (rain below 7500-8000 ft and snow above 8000 ft). The forecast calls for daytime highs about 10 degrees cooler than yesterday. Sunny skies should return tomorrow and temperatures should remain on the cooler side.

CONDITIONS ALONG THE SIERRA CREST BETWEEN 8200 FT. AND 9200 FT. IN THE LAST 24 HOURS
Weather Station Map
Weather Station Table
6am temperature: 31 to 35 deg. F.
Max. temperature: 44 to 53 deg. F.
Average ridgetop wind direction: WSW yesterday shifting to ENE during the night
Average ridgetop wind speed: 10 to 15 mph
Maximum ridgetop wind gust: 44 mph
New snowfall: 0 inches
Total snow depth: 62 to 82 inches
Two-Day Mountain Weather Forecast Produced in partnership with the Reno NWS
For 7000 ft. to 8000 ft.
Sunday Sunday Night Monday
Weather: Mostly cloudy then becoming partly cloudy. Chance of showers in the afternoon. Snow levels 7500 to 8000 feet. Chance of precipitation is 25%. Mostly cloudy then becoming partly cloudy. Slight chance of showers in the evening. Snow levels 7500 feet decreasing to below 7000 feet after midnight. Chance of precipitation is 15%. Sunny. Snow levels below 7000 feet. Chance of precipitation is 5%.
Temperatures: 43 to 49 deg. F. 24 to 29 deg. F. 42 to 48 deg. F.
Mid Slope Winds: Northeast around 10 mph. Northwest 10-15 mph. Light winds.
Expected snowfall: 70% probability no accumulation. | SWE = less than 0.10 inch. No accumulation. | SWE = less than 0.10 inch. No accumulation. | SWE = none.
For 8000 ft. to 9000 ft.
Sunday Sunday Night Monday
Weather: Mostly cloudy then becoming partly cloudy. Chance of showers in the afternoon. Snow levels 7500 to 8000 feet. Chance of precipitation is 30%. Mostly cloudy then becoming partly cloudy. Slight chance of showers in the evening. Snow levels 7500 feet decreasing to below 7000 feet after midnight. Chance of precipitation is 20%. Sunny. Snow levels below 7000 feet. Chance of precipitation is 5%.
Temperatures: 37 to 43 deg. F. 22 to 27 deg. F. 36 to 42 deg. F.
Ridge Top Winds: North around 15 mph. Northwest around 15 mph with gusts to 25 mph after midnight. North around 15 mph with gusts to 30 mph.
Expected snowfall: 70% probability no accumulation. | SWE = less than 0.10 inch. No accumulation. | SWE = less than 0.10 inch. 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