THIS AVALANCHE FORECAST EXPIRED ON May 3, 2020 @ 6:54 am
Avalanche Forecast published on May 2, 2020 @ 6:54 am
Issued by Andy Anderson - Tahoe National Forest - Sierra Avalanche Center

A good overnight refreeze and cooler weather should allow a longer window for supportable snow today, but avalanches of loose wet snow may still be possible this afternoon once the surface crust melts. Cornice fall will also remain possible. By this afternoon MODERATE avalanche danger will exist at all elevations. The last avalanche forecast for the season will be on Sunday, May 3rd.

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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Clear skies and near-freezing temperatures during the night have left firm snow surfaces and a thick layer of refrozen snow on many slopes this morning. Cooler temperatures and increased wind should help slow down the melting that occurs today. As a result, the window for supportable snow will last longer. Still, it is May, and cooler weather means daytime highs in the 50's above 7000 ft. and long hours of intense sunshine on all aspects so the supportable snow is unlikely to last all day. By this afternoon the overnight refreeze should melt away exposing deep wet snow on some slopes and loose wet avalanches will become possible on steep slopes. 

Expect soft wet snow to form on E-SE-S aspects first and move to all other aspects as the day warms up. Once the snow starts getting wet and deep, it is time to avoid avalanche terrain by recreating on lower angle terrain without steep slopes above.

Avalanche Problem 2: Cornice
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Falling cornices still represent a potential problem. Large pieces could break off of these overhanging waves of snow as they melt. These blocks of snow could injure a person and may entrain more wet snow or trigger a loose wet avalanche when they impact the slopes below them.

Cornices often break farther back from their edges than expected or at unexpected times. Staying far away from the edges of cornices and not traveling underneath cornices can help avoid this problem.

recent observations
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* Spring melt-freeze conditions exist on all aspects and at elevations across the forecast area. Melting has also resulted in many areas of bare ground on southerly aspects and in areas below 7300 ft. 

* Observations from Round Top (Carson Pass area) and Mt. Houghton (Mt. Rose backcountry) yesterday both showed a much better refreeze than in previous days. Supportable snow lasted into the afternoon even on sunny aspects. In both of these areas, sun cups and runnels have formed on the snow surface. 

* Numerous glide cracks exist where the snowpack overlies steep slabs of rock. No signs of glide avalanches have been reported.

Weather and CURRENT CONDITIONS
weather summary

Last night was mostly clear with temperatures that fell into the 30's. Some unsettled weather moving across northern NV will bring slightly cooler temperatures and increased SW winds today. Some cloud cover could develop this afternoon with a slight chance of thunderstorms north of I80. Expect more of the same for tomorrow. 

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 39 deg. F.
Max. temperature: 45 to 53 deg. F.
Average ridgetop wind direction: SW
Average ridgetop wind speed: 10 to 15 mph
Maximum ridgetop wind gust: 36 mph
New snowfall: 0 inches
Total snow depth: 27 to 60 inches
Two-Day Mountain Weather Forecast Produced in partnership with the Reno NWS
For 7000 ft. to 8000 ft.
Saturday Saturday Night Sunday
Weather: Partly cloudy. Snow levels 7500 feet increasing to 8500 feet in the afternoon. Chance of precipitation is 5%. Clear. Snow levels 8500 feet decreasing to 7500 feet after midnight. Chance of precipitation is 5%. Sunny. Snow levels 7000 feet increasing to 8000 feet in the afternoon. Chance of precipitation is 5%.
Temperatures: 51 to 57 deg. F. 30 to 35 deg. F. 50 to 56 deg. F.
Mid Slope Winds: Southwest 15 to 30 mph with gusts to 50 mph. Southwest 15 to 25 mph. Gusts up to 50 mph decreasing to 35 mph after midnight. Light winds becoming southwest around 15 mph in the afternoon. Gusts up to 30 mph.
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: Partly cloudy. Snow levels 7500 feet increasing to 8500 feet in the afternoon. Chance of precipitation is 5%. Clear. Snow levels 8500 feet decreasing to 7500 feet after midnight. Chance of precipitation is 5%. Sunny. Snow levels 7000 feet increasing to 8000 feet in the afternoon. Chance of precipitation is 5%.
Temperatures: 44 to 52 deg. F. 28 to 33 deg. F. 45 to 51 deg. F.
Ridge Top Winds: Southwest 15 to 30 mph with gusts to 55 mph. Southwest 15 to 30 mph with gusts to 55 mph. Southwest 15 to 25 mph. Gusts up to 45 mph decreasing to 35 mph in the afternoon.
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