The last avalanche forecast for the 2023-2024 season posted on April 21st. Thank you to all who contributed to the avalanche center this season through observations, volunteer time, and/or financial contributions.
This Avalanche Advisory was published on March 13, 2011:
March 13, 2011 at 7:00 am | |
Near and above treeline, avalanche danger is LOW with very isolated pockets of MODERATE danger on N-NE-E aspects on slopes 37 degrees and steeper. Below treeline LOW avalanche danger exists on all aspects. As more snow and wind impact the region tonight the avalanche danger will quickly increase. |
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Forecast Discussion:
A low pressure system approaching the forecast area should cause the winds to increase throughout the day. This system will also push more clouds and a chance for some light snow into the region today. The forecast calls for snowfall to increase overnight. Snow levels should start around 7000 ft today and drop to below lake level during the night. By tomorrow morning 6-10 inches of new snow could accumulate above 7000 ft. As the storm continues eastward on Monday, snowfall should taper off, the winds should decrease, and the clouds should start to break up.
Stability tests, ski cuts, and general observations on Mt. Judah/Anderson Ridge and on Incline Lake Peak showed a mostly stable snowpack. In areas where dense, hard wind slabs existed, tests showed that the bonds between these slabs and the snow below them continue to gain strength. No skier triggered cracking occurred in either of these areas on wind-loaded slopes yesterday.
A wide variety of conditions exists on the snow surface across the region. On the northerly aspects in shaded areas sheltered from the winds, patches of soft snow mixed with breakable and supportable crusts comprise the snow surface. Larger areas of soft snow remain on the sheltered northerly slopes at higher elevations. In the wind affected areas on the northerly aspects, firm wind packed snow exists. On the more sun-exposed aspects above 8000 ft, the snow surface remained frozen yesterday. On a SE aspect on Mt. Judah between 7400 ft and 8000 ft, enough melting occurred for some corn-like conditions to form. Below 7400 ft on the sun-exposed aspects, the snow quickly became wet and sticky in that area.
Primary Avalanche Concern: Hard Wind Slabs
Observations show that the bonds between the hard wind slabs and the softer snow below them continue to gain strength; however, human triggered avalanches due to failure of these wind slabs will remain possible in some isolated pockets of terrain. Steep, wind-loaded, N-NE-E facing complex and extreme terrain near and above treeline hold the best potential for these lingering instabilities especially in areas with unsupported wind-loaded slopes. These slabs exhibit hard slab characteristics meaning that they are more likely to break above the person who triggers them and could break after several people have already weighted the slope. Larger triggers like multiple people on a slope or large cornices will have better chances of causing avalanche activity. Even though these slabs should remain limited to isolated pockets of terrain and should be more difficult to trigger today, they could have serious consequences if they do break. Use caution and evaluate slopes carefully before committing to them especially in areas where these hard slabs exist.
As more snow and wind impact the region tonight the avalanche danger will quickly increase.
The bottom line:
Near and above treeline, avalanche danger is LOW with very isolated pockets of MODERATE danger on N-NE-E aspects on slopes 37 degrees and steeper. Below treeline LOW avalanche danger exists on all aspects. As more snow and wind impact the region tonight the avalanche danger will quickly increase.
Weather Observations from along the Sierra Crest between 8200 ft and 8800 ft:
0600 temperature: | 24-30 deg. F. |
Max. temperature in the last 24 hours: | 31-38 deg. F. |
Average wind direction during the last 24 hours: | Southwest |
Average wind speed during the last 24 hours: | 25-30 mph |
Maximum wind gust in the last 24 hours: | 60 mph |
New snowfall in the last 24 hours: | O inches |
Total snow depth: | 90-128 inches |
Two-Day Mountain Weather Forecast - Produced in partnership with the Reno NWS
For 7000-8000 ft: |
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Sunday: | Sunday Night: | Monday: | |
Weather: | Mostly cloudy with a chance of snow | Snow | Mostly cloudy with a chance of snow in the morning becoming a slight chance of snow in the afternoon |
Temperatures: | 39-45 deg. F. | 20-25 deg. F. | 40-44 deg. F. |
Wind direction: | Southwest | Southwest | Southwest |
Wind speed: | 10-15 mph with gusts to 40 mph increasing to 15-25 mph with gusts to 50 mph in the afternoon | 20-30 mph with gusts to 55 mph | 15-25 mph with gusts to 45 mph |
Expected snowfall: | up to .5 in. | 4-8 in. | trace in. |
For 8000-9000 ft: |
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Sunday: | Sunday Night: | Monday: | |
Weather: | Mostly cloudy with a chance of snow | Snow | Mostly cloudy with a chance of snow in the morning becoming a slight chance of snow in the afternoon |
Temperatures: | 33-38 deg. F. | 18-23 deg. F. | 34-40 deg. F. |
Wind direction: | Southwest | Southwest | Southwest |
Wind speed: | 25-35 mph with gusts to 50 mph increasing to 35-50 mph with gusts to 80 mph in the afternoon | 40-55 mph with gusts to 80 mph | 35-45 mph with gusts to 60 mph |
Expected snowfall: | up to .5 in. | 6-10 in. | trace in. |