This avalanche advisory is provided through a partnership between the Tahoe National Forest and the Sierra Avalanche Center. This advisory 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 advisory applies only to backcountry areas outside established ski area boundaries. This advisory describes general avalanche conditions and local variations always occur. This advisory expires 24 hours after the posted time unless otherwise noted. The information in this advisory is provided by the USDA Forest Service who is solely responsible for its content.

Another warm, sunny day is on tap for the forecast area with temperatures forecasted to reach into the upper 40's and low 50's above 8000' again. A low pressure system moving through the Pacific Northwest should push a slight disturbance southward causing the southwest winds to increase and causing some high clouds to form over the Central Sierra today. These clouds should become more widespread tonight. By tomorrow there is a slight chance for some showers and maybe even a thunderstorm or two.

Observations:

Observations on Silver Peak (Pole Creek Drainage) showed heavy, wet snow on the surface on all aspects that received sun up to 8000' by mid day. On the E-SE-S aspects 2-3 inches of wet snow existed on the surface. Some skier-triggered roller balls and wet snow sluffs did occur on steep (38-40 degree) E-SE facing test slopes between 7000' and 8000'. On the N-NE aspects, the shaded areas still held cold, soft snow. On the sunny N-NE aspects or in sunny spots on those aspects, sticky, moist snow existed on the surface up to 8000'. Layer bonding tests and snowpit tests near the crown of an avalanche that happened on Friday night (photos) showed that the storm snow weaknesses in the new snow have gained strength leaving a mostly stable snowpack on the NW-N-NE aspects. On Red Lake Peak (near Carson Pass), observers reported similar conditions with 2-4 inches of wet snow on the surface of the S-SE aspects up to 9000'. Above 9000' only the surface (1cm) of the snowpack was wet with cold snow underneath it. On the more northerly aspects on Red Lake Peak the snow remained cold and soft above 9000'.

Avalanche concerns: Warming instability

More sunshine and daytime highs in the mid 40's to low 50's will make avalanches due to daytime warming the main avalanche concern again today. Several melt-freeze cycles over the last few days, a strong overnight refreeze due to radiational cooling, and some increased cloud cover this afternoon will work against the sun and warmth to make these wet-snow instabilities less likely and less widespread today. Most of the wet snow instabilities should manifest as surface instabilities like roller-balls and pinwheels (some of these may even occur on the low elevation northerly aspects). However, some wet snow point releases and slab avalanches will remain possible. Some natural point-release and roller ball activity may also occur today on the most sun exposed aspects especially on steep slopes near rocks and cliffs. The sun-exposed E-SE-S-SW-W aspects below 9000' hold the greatest potential for more serious wet-snow instabilities with the risk increasing at lower elevations.

The bottom line:

On slopes steeper than 35 degrees, the avalanche danger will rise to MODERATE on the sun-exposed E-SE-S-SW-W aspects due to daytime warming today. On the NW-N-NE aspects the avalanche danger will remain LOW.

Andy Anderson - Avalanche Forecaster, Tahoe National Forest

Weather Observations from along the Sierra Crest between 8200 ft and 8800 ft:

0600 temperature:	36 deg. F.
Max. temperature in the last 24 hours:	42-53 deg. F.
Average wind direction during the last 24 hours:	Southwest
Average wind speed during the last 24 hours:	Since noon yesterday: 25 mph
Maximum wind gust in the last 24 hours:	44 mph
New snowfall in the last 24 hours:	O inches
Total snow depth:	91-128 inches

Two-Day Mountain Weather Forecast - Produced in partnership with the Reno NWS

For 7000-8000 ft:
	Tuesday:	Tuesday Night:	Wednesday:
Weather:	Sunny this morning with high clouds developing during the day. Partly sunny by this afternoon.	High clouds becoming more widespread and thicker.	Partly cloudy with a slight chance of showers and maybe some thunderstorms.
Temperatures:	46-53 deg. F.	34-45 deg. F.	46-53 deg. F.
Wind direction:	Southwest	West	Variable
Wind speed:	10-15 mph with gusts to 25 mph	10-15 mph becoming light after midnight	up to 10 mph
Expected snowfall:	O in.	O in.	O in.
For 8000-9000 ft:
	Tuesday:	Tuesday Night:	Wednesday:
Weather:	Sunny this morning with high clouds developing during the day. Partly sunny by this afternoon.	High clouds becoming more widespread and thicker.	Partly cloudy with a slight chance of showers and maybe some thunderstorms.
Temperatures:	40-50 deg. F.	28-35 deg. F.	46-52 deg. F.
Wind direction:	Southwest	Southwest shifting to the south	Variable becoming west in the afternoon
Wind speed:	15-30 mph with gusts to 55 mph	15-30 with gusts to 55 mph decreasing to 10 mph after midnight	up to 10 mph
Expected snowfall:	O in.	O in.	O in.