THIS AVALANCHE FORECAST EXPIRED ON March 6, 2019 @ 6:48 am
Avalanche Forecast published on March 5, 2019 @ 6:48 am
Issued by Steve Reynaud - Tahoe National Forest

MODERATE avalanche danger will exist due to wind slab and loose wet avalanche problems as another warm storm impacts our forecast area starting this afternoon.  Human triggered avalanche activity remains possible.

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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Reactive wind slabs could still exist on NW-N-NE-E-SE aspects in near and above treeline terrain.  Increasing S/SW winds today along with additional snow starting this afternoon will create new wind slabs in wind exposed areas.  Warming and/or rain during the storm could make wind slab avalanches easier to trigger as they could take on wet slab characteristics.

Look for blowing snow, cornice formation, and wind pillows.  Large cornices exist throughout the forecast area along exposed ridges and could pose travel concerns.

Avalanche Problem 2: Loose Wet
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As this next storm impacts our area, warming conditions with the possibility of rain could make loose wet avalanches possible on all aspects in near and below treeline terrain.  Most of this loose wet activity should be in the form of roller balls, but larger avalanches that involve more snow could be possible in isolated areas.  If rain levels go higher than forecasted, more widespread avalanche activity would be expected.

Terrain hazards like rocks, trees, or cliffs, could increase the consequences of being caught in even a small loose wet avalanche.  Small roller ball activity or pinwheels may be a precursor to larger loose wet avalanches to come.

recent observations

*  A skier triggered avalanche occurred in Crater Bowl on Red Lake Peak (Carson Pass area) yesterday.  Avalanche was reported as a D2, on a NE slope at 9500', and ran 1000' downslope.

*  Multiple recent avalanches reported from Carson Pass and Echo Pass that occurred on Sunday during warming conditions.  These avalanches occurred on multiple aspects and elevations and had wet slab/loose wet characteristics.

*  Warming was limited yesterday in many areas due to cloud cover and light winds. 

Weather and CURRENT CONDITIONS
weather summary

Another storm moves into our area this afternoon through Thursday.  This AR storm is splitting and sending the majority of the moisture into the southern Sierra.   Warm subtropical moisture will be approaching today with snow levels forecasted to be around 6500'.  Light snow is expected starting this afternoon and overnight.  Heavier snow is forecasted during the day on Wednesday with up to 1' of snow possible above 8000'.  Unsettled weather continues Thursday into Friday with more chances for snow and colder temperatures.

Weather observations from along the Sierra Crest between 8200 ft. and 8800 ft.
0600 temperature: 21 to 30 deg. F.
Max. temperature in the last 24 hours: 35 deg. F.
Average wind direction during the last 24 hours: S/SW
Average wind speed during the last 24 hours: 30 to 45 mph
Maximum wind gust in the last 24 hours: 62 mph
New snowfall in the last 24 hours: 0 inches
Total snow depth: 119 to 127 inches
Two-Day Mountain Weather Forecast Produced in partnership with the Reno NWS
For 7000 ft. to 8000 ft.
Tuesday Tuesday Night Wednesday
Weather: Cloudy. Slight chance of snow in the morning, then snow in the afternoon. Snow levels below 7000 feet. Chance of precipitation is 75%. Cloudy. Rain in the evening. Snow through the night. Snow levels 7000 feet. Chance of precipitation is 75%. Cloudy. Snow through the day. Slight chance of thunderstorms in the afternoon. Snow levels below 7000 feet. Chance of precipitation is 95%.
Temperatures: 32 to 37. deg. F. 26 to 31. deg. F. 33 to 38. deg. F.
Mid Slope Winds: Light winds becoming south around 15 mph with gusts to 50 mph in the afternoon. South 15 to 25 mph with gusts to 70 mph. South 15 to 30 mph with gusts to 70 mph.
Expected snowfall: 70% probability of 1 to 2 inches. 30% probability of 2 to 3 inches. | SWE = up to 0.20 inch. 70% probability of 1 to 4 inches. 30% probability of 4 to 8 inches. | SWE = 0.15-0.40 inch. 80% probability of 6 to 10 inches. 20% probability of 10 to 15 inches. | SWE = 0.55-0.80 inch.
For 8000 ft. to 9000 ft.
Tuesday Tuesday Night Wednesday
Weather: Cloudy. Slight chance of snow in the morning, then snow in the afternoon. Snow levels below 7000 feet. Chance of precipitation is 80%. Cloudy. Snow. Snow levels 7000 feet. Chance of precipitation is 80%. Cloudy. Snow through the day. Slight chance of thunderstorms in the afternoon. Snow levels below 7000 feet. Chance of precipitation is 95%.
Temperatures: 29 to 35. deg. F. 22 to 27. deg. F. 29 to 35. deg. F.
Ridge Top Winds: South 20 to 35 mph with gusts to 60 mph increasing to 30 to 45 mph with gusts to 80 mph in the afternoon. South 30 to 50 mph with gusts to 80 mph. South 35 to 55 mph with gusts to 95 mph.
Expected snowfall: 70% probability of 1 to 2 inches. 30% probability of 2 to 4 inches. | SWE = 0.15-0.25 inch. 70% probability of 2 to 5 inches. 30% probability of 5 to 9 inches. | SWE = 0.15-0.40 inch. 80% probability of 8 to 12 inches. 20% probability of 12 to 16 inches. | SWE = up to 0.85 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