THIS AVALANCHE FORECAST EXPIRED ON April 14, 2019 @ 6:59 am
Avalanche Forecast published on April 13, 2019 @ 6:59 am
Issued by Andy Anderson - Tahoe National Forest - Sierra Avalanche Center

LOW avalanche danger will exist while the snow remains frozen and supportable early this morning. The danger will quickly increase to MODERATE as loose wet avalanche problems become possible due to rapid warming and strong sunshine. 

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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    Certain
    Very Likely
    Likely
    Possible
    Unlikely
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    Large
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A thick supportable melt/freeze crust exists above a layer of wet snow on most slopes across the region. Rapid warming and strong sunshine today should cause this crust to melt quickly. Once it melts loose wet avalanches will become possible. These could entrain enough wet snow to cause problems for backcountry travelers, especially on long, steep, sun-exposed slopes. 

Conditions will change quickly today and could go from frozen and supportable to loose and wet in a short amount of time. Rollerballs, pinwheels, and boot-top deep wet snow can provide clues that larger loose wet avalanches may soon be possible and that recreation conditions are getting wet and sloppy. As soon as the snow starts becoming unsupportable, it is time to call it a day or move to low angle slopes.    

recent observations

* Observations from Donner Summit and Jakes Peak yesterday found frozen supportable melt/freeze crusts on all aspects in the morning. By noon enough warming had occurred for corn conditions to exist at the lower elevations. Upper elevations on Jakes still remained firm.

* By 12:30 pm yesterday on S-SE-E aspects at ~7000 ft on Donner Summit, conditions started to become unsupportable to a person on foot and ankle deep wet snow existed. 

Weather and CURRENT CONDITIONS
weather summary

Temperatures at the upper elevations started warming quickly around 4 am as warm air moved into the region. Sensors above 8000 ft were already reporting temperatures in the mid to upper 30's as of 6 am. The lower elevations should start warming once the sun comes up. Temperatures should continue to rise today with daytime highs topping out in the 50's above 7000 ft and near 60 at Lake Level. Some small systems passing north of the area should bring a few clouds and slightly cooler weather to the region tomorrow. 

Weather observations from along the Sierra Crest between 8200 ft. and 8800 ft.
0600 temperature: 27 to 38 deg. F.
Max. temperature in the last 24 hours: 38 to 46 deg. F.
Average wind direction during the last 24 hours: NE shifting to SW after 4 am
Average wind speed during the last 24 hours: 15 to 20 mph
Maximum wind gust in the last 24 hours: 48 mph
New snowfall in the last 24 hours: 0 inches
Total snow depth: 105 to 154 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. Snow levels below 7000 feet increasing to 8000 feet in the afternoon. Chance of precipitation is 0%. Partly cloudy then becoming clear. Snow levels 8500 feet. Chance of precipitation is 0%. Partly cloudy. Snow levels 7500 feet increasing to 8500 feet in the afternoon. Chance of precipitation is 10%.
Temperatures: 50 to 56 deg. F. 29 to 36 deg. F. 46 to 52 deg. F.
Mid Slope Winds: Light winds. Gusts up to 25 mph in the afternoon. Southwest around 15 mph. Gusts up to 30 mph increasing to 40 mph after midnight. Southwest 15 to 20 mph with gusts to 45 mph increasing to 15 to 30 mph with gusts to 65 mph in the afternoon.
Expected snowfall: No accumulation. | SWE = none. No accumulation. | SWE = none. No accumulation. | SWE = none.
For 8000 ft. to 9000 ft.
Saturday Saturday Night Sunday
Weather: Sunny. Snow levels below 7000 feet increasing to 8000 feet in the afternoon. Chance of precipitation is 0%. Partly cloudy then becoming clear. Snow levels 8500 feet. Chance of precipitation is 0%. Partly cloudy. Snow levels 7500 feet increasing to 8500 feet in the afternoon. Chance of precipitation is 10%.
Temperatures: 44 to 52 deg. F. 27 to 36 deg. F. 40 to 48 deg. F.
Ridge Top Winds: West around 15 mph with gusts to 25 mph. Southwest 15 to 30 mph. Gusts up to 30 mph increasing to 50 mph after midnight. Southwest 25 to 35 mph increasing to 30 to 45 mph in the afternoon. Gusts up to 70 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