THIS AVALANCHE ADVISORY EXPIRED ON April 6, 2017 @ 6:50 am
Avalanche Advisory published on April 5, 2017 @ 6:50 am
Issued by Brandon Schwartz - Tahoe National Forest

Areas of MODERATE avalanche danger may exist this morning in locations that did not refreeze last night. In areas that did refreeze last night, MODERATE avalanche danger will develop at all elevations as daytime warming progresses. Loose wet avalanche problems are expected today at all elevations. Last night's snow surface refreeze is expected to have been relatively poor in the areas where it occurred.

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
  • Size ?
    Historic
    Very Large
    Large
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Above freezing air temperatures and periods of cloud cover last night are expected to have produced a relatively poor overnight snow surface refreeze. Forecast cloud cover this morning may slow the snow surface melt rate, possibly leading to a widow of supportable travel conditions on open slopes early this morning.  If skies are sunny, expect areas of instability to form rapidly. Areas of loose wet instability will develop at all elevations in response to daytime warming on E-SE-S-SW-W aspects as well as lower elevation NW-N-NE aspects.

If little to no evidence of snow surface refreeze from last night exists in treed areas, know that any refreeze that exists on open slopes is fairly poor and very superficial. When surface snow becomes unsupportable and deep wet snow is exposed, it is time to move to a colder aspect, slopes less than 30 degrees in slope angle without steeper terrain above, or leave the area.

recent observations

Observations were made yesterday on Castle Peak (Donner Summit area) and on Squaw Ridge near Silver Lake (Carson Pass area). In both locations, a decent to good snow surface refreeze lasted into the mid day hours. Greater than forecast cloud cover slowed the snow surface melt rate and extended the window of supportable travel conditions. By the afternoon hours, deep wet snow with some signs of instability was observed in wind protected areas.

Weather and CURRENT CONDITIONS
weather summary

Warm and cloudy conditions are expected today. Some sun breaks could occur, but significant amounts of mid and high level cloud cover are forecast. Ridgetop winds out the of SW will steadily increase today, this afternoon, and tomorrow ahead of an approaching storm system. Ridgetop gusts are expected to reach 50 mph today and 100 mph tomorrow. Tomorrow will be a few degrees colder with continued mostly cloudy skies and a slight chance of light precipitation in the afternoon. A powerful storm system is expected to begin impacting the region late tomorrow night. More information is available on this storm from NWS Reno.

 

Weather observations from along the Sierra Crest between 8200 ft. and 8800 ft.
0600 temperature: 35 to 41 deg. F.
Max. temperature in the last 24 hours: 45 to 51 deg. F.
Average wind direction during the last 24 hours: SW
Average wind speed during the last 24 hours: 25 mph
Maximum wind gust in the last 24 hours: 51 mph
New snowfall in the last 24 hours: 0 inches
Total snow depth: 114 to 172 inches
Two-Day Mountain Weather Forecast Produced in partnership with the Reno NWS
For 7000 ft. to 8000 ft.
Wednesday Wednesday Night Thursday
Weather: Mostly cloudy skies. Mostly cloudy skies. Mostly cloudy skies. A slight chance of rain and snow.
Temperatures: 51 to 56 deg. F. 32 to 37 deg. F. 44 to 49 deg. F.
Wind Direction: SW SW S
Wind Speed: Light winds increasing to 10 to 20 mph with gusts to 35 mph in the afternoon. 15 to 25 mph with gusts to 45 mph. 15 to 25 mph increasing to 25 to 35 mph in the afternoon. Gusts up to 65 mph.
Expected snowfall: 0 in. 0 in. Up to 1 in.
For 8000 ft. to 9000 ft.
Wednesday Wednesday Night Thursday
Weather: Mostly cloudy skies. Mostly cloudy skies. Mostly cloudy skies. A slight chance of rain and snow in the afternoon.
Temperatures: 46 to 54 deg. F. 31 to 36 deg. F. 39 to 47 deg. F.
Wind Direction: SW SW SW
Wind Speed: 15 to 20 mph with gusts to 40 mph, increasing to 20 to 30 mph with gusts to 50 mph in the afternoon. 25 to 40 mph. Gusts to 70 mph increasing to 80 mph after midnight. 30 to 50 mph with gusts to 100 mph.
Expected snowfall: 0 in. 0 in. Up to 1 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