THIS AVALANCHE FORECAST EXPIRED ON January 25, 2019 @ 7:00 am
Avalanche Forecast published on January 24, 2019 @ 7:00 am
Issued by Andy Anderson - Tahoe National Forest - Sierra Avalanche Center

LOW avalanche danger exists for all elevations today. "LOW danger" does not mean "no danger". Continue to use normal caution while traveling in the backcountry to minimize the chances of an unpleasant surprise.

1. Low

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Above Treeline
Generally safe avalanche conditions. Watch for unstable snow on isolated terrain features.

1. Low

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Near Treeline
Generally safe avalanche conditions. Watch for unstable snow on isolated terrain features.

1. Low

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Below Treeline
Generally safe avalanche conditions. Watch for unstable snow on isolated terrain features.
    Generally safe avalanche conditions. Watch for unstable snow on isolated terrain features.
Avalanche Problem 1: Normal Caution
  • Type ?
  • Aspect/Elevation ?
  • Likelihood ?
    Certain
    Very Likely
    Likely
    Possible
    Unlikely
  • Size ?
    Historic
    Very Large
    Large
    Small

Avalanche activity large enough to bury a person has become unlikely across the forecast area. Unlikely does not mean impossible and some avalanche activity could still occur in the form of small inconsequential wet snow instabilities (roller balls, pinwheels or small sluffs) or a cornice failure or maybe a small isolated wind slab. Deep slabs have become even more unlikely due to strength gains in the persistent weak layers and the strong snow above those layers. Still, this problem may not be impossible in an isolated spot with a large enough trigger (large cornice failures, etc). Crusts, scoured surfaces, and wet snow should dominate the sun and wind exposed slopes with some chance for softer snow on sheltered, shaded northerly aspects.  

Complex terrain with steep cliffy areas, overlapping avalanche paths, unsupported slopes, and lots of trigger points could represent some of the isolated areas where a surprise might still happen or where a small avalanche could have consequences. Make a plan that anticipates conditions and creates safety margins before heading out today. Maintain awareness of the conditions and terrain and stop to talk with your group to identify any isolated areas where problems may still linger. Manage your group with safe travel techniques like traveling one at a time through avalanche terrain. 

recent observations

* Observations from Porcupine Ridge, the Mt. Rose backcountry, and Castle Peak all found wind scoured surfaces on a variety of aspects in wind exposed near and above treeline areas. New and old cornices existed along ridgelines and the ones on the N-NE-E facing slopes were scoured by northerly winds. 

* Warm, wet, and sticky surface snow existed by mid-day on any sun-exposed slopes in all of these areas. Snow remained cold and dry on shaded northerly aspects. Small loose wet snow instabilities including roller balls, pinwheels, and sluffs were reported on southerly aspects of Castle Peak, Porcupine Ridge, and Incline Lake Peak. 

* Snowpit data from Porcupine Ridge yielded similar results to data from Hidden Peak and Silver Peak earlier this week and indicated that the old persistent weak layers continue to gain strength.

 

Weather and CURRENT CONDITIONS
weather summary

Cold air trapped in the valleys and with warm air above has led to inversion conditions this morning. Upper elevation remote sensors have already reached temperatures in the upper 20's to low 30's while lower elevations have dropped into the low to mid 20's. East and northeast winds should continue to decrease today before increasing slightly tomorrow. Temperatures should warm over the next few days and skies should remain sunny and clear as a high-pressure ridge builds across the region. 

CONDITIONS ALONG THE SIERRA CREST BETWEEN 8200 FT. AND 9200 FT. IN THE LAST 24 HOURS
6am temperature: 25 to 33 deg. F.
Max. temperature: 38 to 44 deg. F.
Average ridgetop wind direction: W and NW to E and NE
Average ridgetop wind speed: 20 to 25 mph
Maximum ridgetop wind gust: 38 mph
New snowfall: 0 inches
Total snow depth: 67 to 90 inches
Two-Day Mountain Weather Forecast Produced in partnership with the Reno NWS
For 7000 ft. to 8000 ft.
Thursday Thursday Night Friday
Weather: Sunny. Clear. Sunny.
Temperatures: 36 to 41 deg. F. 22 to 27 deg. F. 40 to 45 deg. F.
Mid Slope Winds: East winds around 10 mph. Gusts up to 20 mph. East winds 5 to 10 mph in the evening then becoming light. Light winds becoming northeast around 10 mph in the afternoon.
Expected snowfall: No accumulation. | SWE = none. No accumulation. | SWE = none. No accumulation. | SWE = none.
For 8000 ft. to 9000 ft.
Thursday Thursday Night Friday
Weather: Sunny. Clear. Sunny.
Temperatures: 33 to 38 deg. F. 22 to 27 deg. F. 36 to 41 deg. F.
Ridge Top Winds: Northeast 10 to 15 mph with gusts to 30 mph. East 10 to 15 mph with gusts to 30 mph in the evening becoming light. West 15 to 25 mph with gusts to 45 mph shifting to the north 15 to 30 mph with gusts to 60 mph in the afternoon.
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