THIS AVALANCHE FORECAST EXPIRED ON March 25, 2019 @ 6:50 am
Avalanche Forecast published on March 24, 2019 @ 6:50 am
Issued by Brandon Schwartz - Tahoe National Forest

MODERATE avalanche danger at all elevations today as rapid warming of recent new snow creates loose wet avalanches.

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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    Very Likely
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Rapid warming of new snow from the past 36 hours will allow for loose wet avalanche activity to occur today in sun exposed areas at all elevations. Avalanche activity will likely be both natural and human triggered today. While loose wet avalanche activity may be fairly widespread today in steep terrain, avalanche size is expected at D1 to D1.5. An isolated size D2 avalanche is not impossible on slopes where long vertical runs are possible. With the increasingly higher sun angle of spring, increasing amounts of loose wet instability are expected on NW-N-NE aspects in addition to the expected instability on the usual E-SE-S-SW-W aspects.

Consequences from a small size D1 avalanche will come from secondary terrain hazards. This means being pushed into rocks, trees, over cliffs, or into terrain traps by what would otherwise be an inconsequential avalanche in simpler terrain. Rollerballs and pinwheels will be the indicators that loose wet instability is present. Use low angle slopes to reduce the hazard as needed. Plan appropriately for the timing of travel in sun exposed avalanche terrain and exit steep terrain before daytime warming creates problematic instability.

recent observations

* Reports were received yesterday of two size D1 to D1.5 wind slab avalanches that were skier/snowboarder triggered near treeline on NE to E aspect terrain on Red Lake Peak (Carson Pass area) and on Incline Lake Peak (Mount Rose area). Crowns were reported at 2 to 5 inches deep, but up to 150' wide.

* Thinning cloud cover was observed around midday yesterday in the Donner Summit area with a sun crust observed to form quickly up to at least 8,100' on Andesite Peak.

* Bonding strength of the most recent storm snow to the melt-freeze crust below it was reported to vary from weak to strong yesterday at various locations around the forecast area.

Weather and CURRENT CONDITIONS
weather summary

A short lived break in the weather will occur today with sunny skies this morning becoming partly cloudy as the day progresses. Rapidly warming air temperatures are expected today as maximum daytime air temperatures climb above freezing. Ridgetop winds are forecast to increase substantially out of the S tonight and tomorrow as a series of storm systems approach the region. A powerful late season storm may bring feet of new snow to the Sierra Crest Tues night/Wed. For the latest info on these upcoming storms, check with NWS Reno.

Weather observations from along the Sierra Crest between 8200 ft. and 8800 ft.
0600 temperature: 13 to 19 deg. F.
Max. temperature in the last 24 hours: 25 to 32 deg. F.
Average wind direction during the last 24 hours: SW
Average wind speed during the last 24 hours: 28 mph
Maximum wind gust in the last 24 hours: 59 mph
New snowfall in the last 24 hours: 1 to 3 inches
Total snow depth: 112 to 159 inches
Two-Day Mountain Weather Forecast Produced in partnership with the Reno NWS
For 7000 ft. to 8000 ft.
Sunday Sunday Night Monday
Weather: Sunny then becoming partly cloudy. Snow levels below 7000 feet. Chance of precipitation is 0%. Mostly cloudy then becoming partly cloudy. Snow levels below 7000 feet. Chance of precipitation is 0%. Partly cloudy then becoming mostly cloudy. Chance of snow in the afternoon. Snow levels below 7000 feet. Chance of precipitation is 35%.
Temperatures: 40 to 45 deg. F. 23 to 29 deg. F. 40 to 46 deg. F.
Mid Slope Winds: Light winds. South around 15 mph. Gusts up to 35 mph after midnight. South 15 to 30 mph. Gusts up to 45 mph increasing to 60 mph in the afternoon.
Expected snowfall: No accumulation. | SWE = none. No accumulation. | SWE = none. 70% probability up to 2 inches. 30% probability of no accumulation. | SWE = up to 0.15 inch.
For 8000 ft. to 9000 ft.
Sunday Sunday Night Monday
Weather: Sunny then becoming partly cloudy. Snow levels below 7000 feet. Chance of precipitation is 0%. Mostly cloudy then becoming partly cloudy. Snow levels below 7000 feet. Chance of precipitation is 0%. Partly cloudy then becoming mostly cloudy. Chance of snow in the afternoon. Snow levels below 7000 feet. Chance of precipitation is 35%.
Temperatures: 35 to 41 deg. F. 20 to 25 deg. F. 35 to 41 deg. F.
Ridge Top Winds: Southwest around 15 mph with gusts to 30 mph. South 15 to 25 mph with gusts to 45 mph increasing to 20 to 35 mph with gusts to 70 mph after midnight. South 30 to 50 mph with gusts to 90 mph.
Expected snowfall: No accumulation. | SWE = none. No accumulation. | SWE = none. 70% probability up to 2 inches. 30% probability of no accumulation. | SWE = up to 0.15 inch.
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