THIS AVALANCHE FORECAST EXPIRED ON April 9, 2019 @ 6:46 am
Avalanche Forecast published on April 8, 2019 @ 6:46 am
Issued by Brandon Schwartz - Tahoe National Forest

MODERATE avalanche danger continues today at all elevations due to an ongoing loose wet avalanche problem. Unstable surface wet snow is expected all day today due to poor overnight refreeze and warm air temperatures.

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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    Very Likely
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A loose wet avalanche problem exists right from the start today as last night's snow surface refreeze is expected to have been weak to nonexistent. Air temperatures were above freezing last night at all locations below 9,000'. Cloud cover will have limited any snow surface refreeze from radiational cooling. A warm mostly cloudy day today with a chance of rain to 9,500' this afternoon will keep conditions prime for loose wet avalanches on all aspects at all elevations. Avalanche size is expected at D1 to D2.

Don't expect to use aspect to avoid surface wet snow instability today. This makes slope angle the go to strategy for reducing loose wet avalanche hazard. When the snow surface is marginally supportable to unsupportable with rollerballs and pinwheels present, make the move to lower angle terrain. Pre plan routes that give options for choice of slope angle so that you have the ability to reduce avalanche hazard.

recent observations

* Observations made yesterday on Stevens Peak (Carson Pass area) noted loose wet avalanche activity of size D1 on a variety of aspects in the area at all elevations. Little to no snow surface refreeze had occurred the night before in areas below about 8,500'. A weak refreeze on top of several inches of weak wet snow existed above 8,500'.

* Debris from a size D2 loose wet avalanche were noted on a SE aspect in the Emerald Bay Chutes early yesterday afternoon. The avalanche is believed to have occurred sometime mid to late morning yesterday. Trigger type is unknown. No report was received.

* Observations targeting wind slabs yesterday on Stevens Peak revealed no evidence of ongoing instability for this avalanche problem. No wind slab avalanches were reported in the past 24 hours.

Weather and CURRENT CONDITIONS
weather summary

High pressure from yesterday is moving off to the east with low pressure approaching the region. For today expect increasing cloud cover this morning, rain this afternoon or evening, well above freezing air temperatures all day, and continued moderate to strong SW ridgetop winds. Snow level will be up around 9,000' to 9,500' today, falling slowly after midnight tonight and then falling rapidly around sunrise tomorrow. Most precipitation with this system is expected as rain with a few inches of snow possible. A chance of thunderstorms exists for Tuesday afternoon. A break in the weather is forecast for Wednesday ahead of more weak precipitation events for the remainder of this week.

Weather observations from along the Sierra Crest between 8200 ft. and 8800 ft.
0600 temperature: 34 to 41 deg. F.
Max. temperature in the last 24 hours: 43 to 49 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: 79 mph
New snowfall in the last 24 hours: 0 inches
Total snow depth: 109 to 158 inches
Two-Day Mountain Weather Forecast Produced in partnership with the Reno NWS
For 7000 ft. to 8000 ft.
Monday Monday Night Tuesday
Weather: Mostly cloudy. Slight chance of rain in the afternoon. Snow levels 9000 to 9500 feet. Chance of precipitation is 15%. Mostly cloudy. Rain likely in the evening, then rain and snow after midnight. Snow levels 9000 feet falling to 7000 feet late. Chance of precipitation is 100%. Mostly cloudy. Chance of snow in the morning, then scattered snow showers and slight chance of thunderstorms in the afternoon. Snow levels below 7000 feet. Chance of precipitation is 50%.
Temperatures: 48 to 54 deg. F. 25 to 30 deg. F. 33 to 39 deg. F.
Mid Slope Winds: Southwest 10 to 20 mph with gusts to 30 mph increasing to 20 to 30 mph with gusts to 50 mph in the afternoon. Southwest 20 to 30 mph with gusts to 60 mph. West 15 to 30 mph with gusts to 50 mph.
Expected snowfall: No accumulation. | SWE = less than 0.10 inch. Up to 2 inches. | SWE = 0.30-0.55 inch. Up to 1 inch. | SWE = less than 0.10 inch.
For 8000 ft. to 9000 ft.
Monday Monday Night Tuesday
Weather: Mostly cloudy. Slight chance of rain and snow in the afternoon. Snow levels 9000 to 9500 feet. Chance of precipitation is 15%. Mostly cloudy. Rain likely in the evening, then snow and rain changing to all snow after midnight. Snow levels 9000 feet falling to 7000 feet late. Chance of precipitation is 100%. Mostly cloudy. Snow likely in the morning, then scattered snow showers and slight chance of thunderstorms in the afternoon. Snow levels below 7000 feet. Chance of precipitation is 50%.
Temperatures: 39 to 49 deg. F. 21 to 27 deg. F. 26 to 32 deg. F.
Ridge Top Winds: Southwest 25 to 45 mph with gusts to 70 mph. Southwest 30 to 45 mph with gusts to 85 to 105 mph. West 20 to 35 mph with gusts to 50 mph.
Expected snowfall: No accumulation. | SWE = less than 0.10 inch. 70% probability of 2 to 4 inches. 30% probability up to 2 inches. | SWE = up to 0.60 inch. Up to 1 inch. | SWE = less than 0.10 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