THIS AVALANCHE FORECAST EXPIRED ON March 4, 2019 @ 6:48 am
Avalanche Forecast published on March 3, 2019 @ 6:48 am
Issued by Brandon Schwartz - Tahoe National Forest

MODERATE avalanche danger exists at all elevations today due to wind slab and loose wet avalanche problems.

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: Wind Slab
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Wind slab avalanches remain possible near treeline and above treeline mainly on NW-N-NE-E-SE aspects due to new snow and moderate to strong SW winds. Avalanche size up to D2 may occur.

Identify the specific terrain features where unstable wind slabs may exist. Ridgetop areas below cornice features and wind pillows are the most suspect. Sensitivity to triggering is expected at stubborn today so don't let your guard down if you are not seeing much in the way of evidence of instability.

Avalanche Problem 2: Loose Wet
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A loose wet avalanche problem is expected to continue today in most areas. Some of these loose wet avalanches may share some characteristics with storm slabs, especially in areas above the rain/snow line. This avalanche problem could occur on any aspect and may occur at upper elevations in addition to occurring at the mid and lower elevations. Avalanche size of D1 is expected with the isolated possibility of size D2.

Expect trigger points at slope convexities and in steeper terrain. Use small test slopes to assess for this avalanche problem. Avoid complex terrain and long steep pitches where this instability is present. Downslope hazards such as cliffs and terrain traps could greatly magnify the consequences of being pushed around by a small avalanche.

recent observations

* Numerous hybrid storm slab/loose wet avalanches (size D1) were intentionally skier triggered yesterday below treeline on NE-E aspects on Jakes Peak (West Shore Tahoe area). Similar instability was triggered by snowmobile near Blue Lakes (Carson Pass area).

* Wet surface snow was reported from Powderhouse Peak (Luther Pass area) with some skier triggered rollerballs present. Similar conditions were reported from Mt. Judah (Donner Summit area).

* Some unstable snowpit test results have been reported on top of the Feb 14 rain crust. In some areas, graupel remains on top of this crust.

Weather and CURRENT CONDITIONS
weather summary

Precipitation continues over the forecast area. Snow level rose to 7,000' to 7,500' yesterday afternoon and last night. Snow level is expected around 6,500' to 7,000' for today but may dip a bit lower at times. Rain and snow are expected to increase today along the Sierra Crest north of Hwy 50. Thunderstorms are possible this evening. Snow level is forecast to lower a little bit further tonight as the storm system tapers off. Clearing skies and sunshine are forecast for Monday. The next series of storm systems are expected to impact the region Tuesday-Friday.

Weather observations from along the Sierra Crest between 8200 ft. and 8800 ft.
0600 temperature: 27 to 32 deg. F.
Max. temperature in the last 24 hours: 32 to 34 deg. F.
Average wind direction during the last 24 hours: SW
Average wind speed during the last 24 hours: 43 mph
Maximum wind gust in the last 24 hours: 77 mph
New snowfall in the last 24 hours: 5 to 9 inches
Total snow depth: 121 to 164 inches
Two-Day Mountain Weather Forecast Produced in partnership with the Reno NWS
For 7000 ft. to 8000 ft.
Sunday Sunday Night Monday
Weather: Cloudy. Snow and rain in the morning, then snow showers in the afternoon. Snow levels 7000 feet. Chance of precipitation is 80%. Mostly cloudy. Chance of thunderstorms in the evening. Snow showers likely through the night. Snow levels below 7000 feet. Chance of precipitation is 65%. Partly cloudy then becoming sunny. Slight chance of snow showers in the morning. Snow levels below 7000 feet. Chance of precipitation is 15%.
Temperatures: 34 to 39 deg. F. 22 to 27 deg. F. 35 to 40 deg. F.
Mid Slope Winds: Southwest around 15 mph with gusts to 40 mph. Southwest around 15 mph with gusts to 35 mph. Southwest around 15 mph with gusts to 30 mph in the morning becoming light.
Expected snowfall: 60% probability of 2 to 6 inches. 40% probability up to 2 inches. | SWE = up to 0.40 inch. 70% probability of 1 to 2 inches. 30% probability of 2 to 4 inches. | SWE = up to 0.15 inch. No accumulation. | SWE = trace amounts.
For 8000 ft. to 9000 ft.
Sunday Sunday Night Monday
Weather: Cloudy. Snow in the morning, then snow showers likely in the afternoon. Snow levels 7000 feet. Chance of precipitation is 80%. Mostly cloudy. Chance of thunderstorms in the evening. Snow showers likely through the night. Snow levels below 7000 feet. Chance of precipitation is 65%. Partly cloudy then becoming sunny. Slight chance of snow showers in the morning. Snow levels below 7000 feet. Chance of precipitation is 15%.
Temperatures: 29 to 35 deg. F. 19 to 24 deg. F. 31 to 37. deg. F.
Ridge Top Winds: Southwest 20 to 30 mph with gusts to 65 mph. Southwest 15 to 30 mph with gusts to 50 mph. Southwest 15 to 25 mph with gusts to 50 mph.
Expected snowfall: 80% probability of 3 to 6 inches. 20% probability up to 3 inches. | SWE = up to 0.45 inch. 70% probability of 1 to 2 inches. 30% probability of 2 to 4 inches. | SWE = up to 0.15 inch. No accumulation. | SWE = trace amounts.
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