THIS AVALANCHE FORECAST EXPIRED ON April 3, 2020 @ 6:59 am
Avalanche Forecast published on April 2, 2020 @ 6:59 am
Issued by Steve Reynaud - Tahoe National Forest

Unstable snowpack conditions will continue today.  A mix of wind slab, persistent slab, and loose wet avalanche problems will exist.  MODERATE avalanche danger will continue at all elevations.

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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Gale force SW winds continued through yesterday transporting snow at the higher elevations.  Below 8500', limited available snow remained for wind transport as warm and wet conditions on Tuesday left wet surface snow and breakable crusts on most aspects.  Above 8500', active snow transport continued with signs of recent wind slab avalanches.  Winds became light overnight and shifted to the NE, they are forecasted to increase this morning with moderate gusts before returning back to light.

Look for signs of previous blowing snow, cornice formation, and wind pillows.  These wind slabs will be dense and could be stubborn to trigger.  Increased warming today could make cornices more fragile.   

 

 

Avalanche Problem 2: Persistent Slab
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Isolated persistent slab avalanches continue to remain a concern throughout the forecast region.  A layer of buried surface hoar sits 1 to 3 feet deep below the snow surface.  Weak layer stabilization is occurring at different rates at different locations, with some areas still showing signs that this weak layer can propagate and cause an avalanche.  On a regional level, these avalanches have become unlikely, but not impossible.  The last persistent slab avalanche occurred 3 days ago on Monday of this week.

These persistent slabs exist on NW-N-NE aspects at all elevations.  An avoidance strategy could utilize slope angles below 30 degrees, pick aspects where the problem does not exist, and avoid terrain connected to where this problem might exist.  Complex terrain with multiple trigger points and areas where other avalanche problems could step down to this persistent weak layer remain potential locations for these avalanches to occur.   Avalanches associated with this weak layer would be large with dense heavy slabs of snow.

Avalanche Problem 3: Loose Wet
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Loose wet avalanches could form today as daytime warming occurs.  High sun angles and intense April sunshine will warm the snow surface on all aspects and elevations throughout the day.  After a good refreeze of the snowpack overnight, snow surface conditions will melt quickly with warmer daytime temperatures and mostly light winds forecasted for today.  Rollerballs and pinwheels will be an indicator that larger loose wet avalanches are possible.   

recent observations
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Observations came in from Red Lake Peak in the Carson Pass area yesterday.  Gale force SW winds with intense snow transport was observed over the higher peaks in this area.  Recent avalanche activity was observed in some of these wind loaded areas.   

Observations from Carpenter Ridge (Independence Lake area) showed breakable crusts from a warm and wet Tuesday.  Blowing snow was limited due to the wet or firm snow surface.  Mixed results were seen on the buried surface hoar layer along with unreactive wind slabs.

Weather and CURRENT CONDITIONS
weather summary

Slightly warmer temperatures with sunny skies are forecasted for our area today.  NE winds should be light with some higher gusts at the upper elevations keeping it cool.  Friday will be warmer before we return back to winter over the weekend.  A moderate Sierra storm is forecasted to start on Saturday with increasing winds and snow that will continue well into next week.

CONDITIONS ALONG THE SIERRA CREST BETWEEN 8200 FT. AND 9200 FT. IN THE LAST 24 HOURS
Weather Station Map
Weather Station Table
6am temperature: 13 to 20 deg. F.
Max. temperature: 25 to 41 deg. F.
Average ridgetop wind direction: SW
Average ridgetop wind speed: 35 to 55 mph
Maximum ridgetop wind gust: 73 mph
New snowfall: 0 inches
Total snow depth: 56 to 79 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. Snow levels below 7000 feet. Chance of precipitation is 0%. Clear. Snow levels below 7000 feet. Chance of precipitation is 0%. Partly cloudy. Snow levels below 7000 feet. Chance of precipitation is 0%.
Temperatures: 37 to 43. deg. F. 19 to 24. deg. F. 40 to 46. deg. F.
Mid Slope Winds: Light winds. Light winds. Gusts up to 25 mph in the evening. Light winds becoming southwest around 15 mph with gusts to 25 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. Snow levels below 7000 feet. Chance of precipitation is 0%. Clear. Snow levels below 7000 feet. Chance of precipitation is 0%. Partly cloudy. Snow levels below 7000 feet. Chance of precipitation is 0%.
Temperatures: 31 to 37. deg. F. 16 to 21. deg. F. 34 to 40. deg. F.
Ridge Top Winds: East around 15 mph with gusts to 30 mph in the morning becoming light. Southwest 15 to 25 mph. Gusts up to 35 mph increasing to 45 mph after midnight. Southwest 15 to 25 mph with gusts to 40 mph.
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