THIS AVALANCHE FORECAST EXPIRED ON March 17, 2019 @ 6:58 am
Avalanche Forecast published on March 16, 2019 @ 6:58 am
Issued by Andy Anderson - Tahoe National Forest - Sierra Avalanche Center

LOW avalanche danger will exist at all elevations this morning while the snowpack remains frozen. As the overnight refreeze melts, the danger will increase to MODERATE at all elevations due to the possibility of 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: Loose Wet
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  • Likelihood ?
    Certain
    Very Likely
    Likely
    Possible
    Unlikely
  • Size ?
    Historic
    Very Large
    Large
    Small

Loose wet avalanches will become possible once daytime warming melts through last night's refreeze. Some of them could be small. Some could be large enough to have more serious consequences, especially on long, steep, sun-exposed slopes. Areas with terrain traps could magnify the severity of this problem. Wet surface snow, pinwheels, and roller balls can foreshadow larger loose wet avalanches.

A frozen snow surface can give way to shallow wet snow on a supportable crust (corn) to deep, unsupportable, sloppy, wet snow in a short amount of time. In many areas, the snow may skip over the corn state today because it has not been through enough melt-freeze cycles. Watch for these changes and time backcountry travel to be off sun-exposed slopes before the deep wet snow forms. Exploring more northerly aspects to find areas where softer cold snow still lingers could also reduce exposure to loose wet avalanche concerns.

recent observations

* Observations from Hidden Peak and Sunrise Bowl yesterday found wind affected snow surfaces in exposed near and above treeline areas. A firm wind slab on top of a softer layer of snow existed on multiple aspects in both places. Tests targetting the wind slabs on NE and SW wind-loaded test slopes on Hidden Peak did not show signs of lingering instability.

* Sheltered northerly aspects above 7500 ft. on Hidden Peak still held cold ankle deep soft snow.

* Wet snow had started to form on sun-exposed E-SE aspects on Hidden Peak by mid-morning. Ski cuts could trigger roller balls and pinwheels by noon. The snow on these aspects had not transistioned to corn yet and was wet and sticky.

Weather and CURRENT CONDITIONS
weather summary

A high-pressure ridge over the region should last into early next week. The forecast calls for warm daytime temperatures with below freezing overnight lows, sunny skies, and calm winds through the weekend.

CONDITIONS ALONG THE SIERRA CREST BETWEEN 8200 FT. AND 9200 FT. IN THE LAST 24 HOURS
6am temperature: 24 to 30 deg. F.
Max. temperature: 32 to 42 deg. F.
Average ridgetop wind direction: E
Average ridgetop wind speed: 15 to 25 mph
Maximum ridgetop wind gust: 34 mph
New snowfall: 0 inches
Total snow depth: 120 to 162 inches
Two-Day Mountain Weather Forecast Produced in partnership with the Reno NWS
For 7000 ft. to 8000 ft.
Saturday Saturday Night Sunday
Weather: Sunny. Snow levels below 7000 feet. Chance of precipitation is 0%. Clear. Snow levels below 7000 feet. Chance of precipitation is 0%. Sunny then becoming partly cloudy. Snow levels below 7000 feet. Chance of precipitation is 0%.
Temperatures: 45 to 50 deg. F. 21 to 27 deg. F. 45 to 50 deg. F.
Mid Slope Winds: Light winds. Light winds. Light winds.
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: Sunny. Snow levels below 7000 feet. Chance of precipitation is 0%. Clear. Snow levels below 7000 feet. Chance of precipitation is 0%. Sunny. Snow levels below 7000 feet. Chance of precipitation is 0%.
Temperatures: 38 to 43 deg. F. 20 to 25 deg. F. 39 to 45 deg. F.
Ridge Top Winds: Light winds. Light winds. Light winds.
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