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.

This advisory was posted on March 25, 2008 7:00 AM

A map of the SAC forecast area is available on our home page.

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Today's Advisory:
The avalanche danger is LOW for most elevations and aspects. Below 8000 ft. isolated areas of MODERATE danger could develop on sun exposed SE-S-SW aspects, 38 degrees and steeper in response to daytime warming.

An approaching cold front should bring increased cloud cover and cooler temperatures to the region today. Southwest winds have already started to increase and should continue to strengthen through tomorrow. As the front moves through the area some isolated snow showers could develop. This front will be coming in from the north and should affect the areas north of Highway 50 the most.

Remote sensors above 7500 ft indicate that air temperatures quickly dropped near and below freezing overnight, and satellite imagery shows that cloud cover was patchy for most of the night. This combination of mostly clear skies and below freezing temperatures should have allowed the snow surfaces that melted yesterday to refreeze overnight. Temperatures should be slightly cooler today with highs only forecast to reach the mid 30's to low 40's above 8000 ft. The clouds that have moved in this morning should increase through the day and should prevent most of the snow surfaces from seeing as much sun today. These conditions should allow the snow surface to remain frozen longer today and should limit any softening and melting that does occur to the top few inches of the snowpack.

If slopes see more sun than is forecasted some areas could experience enough melting and weakening for some isolated pockets of human triggerable wet snow instabilities to form. These pockets should be limited to steep, southerly, sun-exposed aspects below 8000 ft where air temperatures could reach into the high 40's today. Wet snow instability that occurs today should be limited to surface snow because the deeper snowpack remains well bonded with established melt water channels to drain free water through the snowpack. Melting of surface snow on higher elevation northerly aspects is not expected to cause wet snow instability at this time. Natural avalanche activity remains unlikely.

The bottom line: The avalanche danger is LOW for most elevations and aspects. Below 8000 ft. isolated areas of MODERATE danger could develop on sun exposed SE-S-SW aspects, 38 degrees and steeper in response to daytime warming.
Public donations to the avalanche center this season are below our fundraising goal. We are going to raffle a beacon, shovel, probe, and backpack package as a way give back to those who donate $100 or more before March 30th. For more information on the raffle and amount of donations received click here.

Andy Anderson, Avalanche Forecaster

Today's Central Sierra Weather Observations:
0600 temperature at Sierra Crest (8,700 feet): 28-32 deg. F
Max. temperature at Sierra Crest past 24 hours: 42-46 deg. F.
Average wind direction at Sierra Crest past 24 hours: Southwest
Average wind speed at Sierra Crest past 24 hours: 35 mph
Maximum wind gust at Sierra Crest past 24 hours: 72 mph
New snowfall at 8,200 feet past 24 hours: 0 inches
Total snow depth at 8,200 feet: 79 inches
Mountain Weather Forecast For Today:
Partly cloudy, cooler, and windy.
Temperature forecast for 8,000 to 9,000 feet: 36 to 44 deg. F
Ridgetop winds forecast for the Sierra Crest: Southwest at 25 to 35 mph with gusts to 50 mph.
Snowfall expected in the next 24 hours: Trace
2 Day Mountain Weather Forecast:

7000 to 8000 Feet:
Today, partly cloudy skies with daytime highs 43 to 51 deg. F. Southwest winds at 10 to 15 mph with gusts to 25 increasing to 15 to 25 mph with gusts to 45 mph in the afternoon.

Tonight, partly cloudy skies with overnight lows 24 to 30 deg. F. Southwest winds at 20 to 30 mph with gusts to 45 mph.

For Wednesday, mostly cloudy skies with a chance of snow showers. Daytime highs 35 to 43 deg. F. Southwest winds at 25 to 35 mph with gusts to 60 mph.

Above 8000 Feet:

Today, partly cloudy skies with daytime highs 36 to 44 deg. F. Southwest winds at 25 to 35 mph with gusts to 50 mph.

Tonight, partly cloudy skies with overnight lows around 23 deg. F. Southwest winds at 20 to 35 mph with gusts to 55 mph increasing to 40 to 50 mph with gusts to 70 mph after midnight.

For Wednesday, mostly cloudy skies with a chance of snow showers. Daytime highs 27 to 35 deg. F. Southwest winds at 40 to 60 mph with gusts to 90 mph.

The bottom line:

Andy Anderson - Avalanche Forecaster, Tahoe National Forest

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

0600 temperature:	deg. F.
Max. temperature in the last 24 hours:	deg. F.
Average wind direction during the last 24 hours:
Average wind speed during the last 24 hours:	mph
Maximum wind gust in the last 24 hours:	mph
New snowfall in the last 24 hours:	O inches
Total snow depth:	inches

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

For 7000-8000 ft:
	Tuesday:	Tuesday Night:	Wednesday:
Weather:
Temperatures:	deg. F.	deg. F.	deg. F.
Wind direction:
Wind speed:
Expected snowfall:	O in.	O in.	O in.
For 8000-9000 ft:
	Tuesday:	Tuesday Night:	Wednesday:
Weather:
Temperatures:	deg. F.	deg. F.	deg. F.
Wind direction:
Wind speed:
Expected snowfall:	O in.	O in.	O in.