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.

Yesterday's snow showers only produced up to 1 inch of new snow across the forecast area. This morning left-over clouds and moisture may produce some isolated snow showers north of Highway 50. South of Highway 50 should be mostly clear today. The winds should shift to the north and increase ahead of a high pressure system building over the forecast area. Warmer temperatures and clearing skies should precede this system today.  By tomorrow the high pressure should bring even warmer temperatures, sunny skies, and moderate westerly winds.

By mid afternoon yesterday, the strong southwest winds had used the new snow in combination with older unconsolidated snow to form wind slabs on leeward slopes. Due to the lack of snow available for transport, these wind slabs remained small and isolated. Only one of the many test slopes in the Mt. Judah area produced a small failure. A 4 foot wide, 4 inch deep wind slab failed on an ENE 39 degree test slope near treeline. This slide only ran for about 3 feet down hill. Other observations from the Mt. Judah area indicated that faceting around the January 2nd rain crust has slowed down. Snowpit tests and hand pits showed that the bond between this layer and the layers of softer snow above and below it are gaining strength. The deeper layers in the snowpack also continue to gain strength.

Even though the snowpack seems to be gaining some strength, two avalanche concerns exist today. First, the north and northwest winds may continue to cross-load the NE-E aspects near and above treeline. This cross-loading could help to increase the size of the wind slabs on these aspects.  Natural failure of these wind slabs remains unlikely today. However, human activity could still trigger small, isolated avalanches involving the snow above the rain crust in the most heavily wind loaded areas. Use clues like wind ripples, drifts, and blowing snow to determine which slopes are wind loaded. Use caution around these slopes.

If the skies do clear, today's second avalanche concern will be instabilities due to daytime warming. The forecast calls for temperatures to rise 8-10 degrees above yesterday's highs. The moderate north winds, low sun angle, and cloud cover should offset this rapid rise in temperature.  These cooling factors should help limit warming instabilities to pinwheels and point release avalanches on sun exposed southerly aspects.

The bottom line:

This morning the avalanche danger is LOW with pockets of MODERATE danger on NE-E aspects near and above treeline. If the sun comes out more pockets of MODERATE danger could develop on sun exposed SE-S-SW-W aspects steeper than 35 degrees by this afternoon.

Andy Anderson - Avalanche Forecaster, Tahoe National Forest

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

0600 temperature:	32 deg. F.
Max. temperature in the last 24 hours:	32 deg. F.
Average wind direction during the last 24 hours:	SW shifting to the NW overnight
Average wind speed during the last 24 hours:	40 mph decreasing to 25 mph
Maximum wind gust in the last 24 hours:	73 mph
New snowfall in the last 24 hours:	0-1 inches
Total snow depth:	64 inches

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

For 7000-8000 ft:
	Tuesday:	Tuesday Night:	Wednesday:
Weather:	Mostly cloudy this morning with a chance for isolated snow showers. Partly cloudy this afternoon. South of Highway 50 partly sunny all day.	Partly cloudy then clearing overnight.	Sunny and warm.
Temperatures:	38-45 deg. F.	24-30 deg. F.	46-52 deg. F.
Wind direction:	Northwest shifting to north	West	West
Wind speed:	10-15 mph with gusts to 25 mph	10 mph	10 mph
Expected snowfall:	O in.	O in.	O in.
For 8000-9000 ft:
	Tuesday:	Tuesday Night:	Wednesday:
Weather:	Mostly cloudy this morning with a chance for isolated snow showers. Partly cloudy this afternoon. South of Highway 50 partly sunny all day.	Partly cloudy then clearing overnight.	Sunny and warm.
Temperatures:	34-41 deg. F.	27-33 deg. F.	41-48 deg. F.
Wind direction:	Northwest shifting to north	North	West
Wind speed:	10-20 mph increasing to 20-30 mph with gusts to 45 mph this afternoon	15-20 mph with gusts to 40 mph	15-20 mph with gusts to 35 mph
Expected snowfall:	O in.	O in.	O in.