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 24, 2008 7:00 AM

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

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Today's Advisory:
This morning, avalanche danger is LOW for all elevations and aspects. Areas of MODERATE danger will develop on sun exposed E-SE-S-SW-W aspects, 38 degrees and steeper in response to daytime warming.

Sunny skies should prevail today although a series of low pressure systems moving through the Pacific Northwest should cause temperatures to be a few degrees cooler today. As these low pressure systems begin to erode the high pressure more winds, some clouds, and a chance for some precipitation should develop starting tonight and lasting for the next few days.

Air temperatures reached the mid 40's above 8000 ft yesterday and should climb close to this range today. Warm air temperatures and intense March sun will melt and soften the snow that refroze last night due to clear skies and overnight air temperatures below freezing. As the snow warms up bonds between the snow grains and snowpack layers will melt and the snow will lose strength until it refreezes. This melt-freeze cycle should affect the snow at all elevations and wet snow instabilities could form on slopes at any elevation today.

Most melting and weakening will occur on the E-SE-S-SW-W aspects due to the sun exposure of these aspects. Wet snow instability that occurs today should be limited to surface snow because the deeper snowpack remains well bonded with established melt water channels in place on southerly aspects. Melting of surface snow on higher elevation northerly aspects is not expected to cause wet snow instability at this time. Human triggered avalanches will become possible, on steep E-SE-S-SW-W aspects as the day warms up. Natural avalanche activity remains unlikely.

The bottom line: This morning, avalanche danger is LOW for all elevations and aspects. Areas of MODERATE danger will develop on sun exposed E-SE-S-SW-W 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): 31 deg. F
Max. temperature at Sierra Crest past 24 hours: 46 deg. F.
Average wind direction at Sierra Crest past 24 hours: Southwest
Average wind speed at Sierra Crest past 24 hours: 20 mph
Maximum wind gust at Sierra Crest past 24 hours: 41 mph
New snowfall at 8,200 feet past 24 hours: 0 inches
Total snow depth at 8,200 feet: 81 inches
Mountain Weather Forecast For Today:
Sunny and warm.
Temperature forecast for 8,000 to 9,000 feet: 40 to 48 deg. F
Ridgetop winds forecast for the Sierra Crest: Southwest at 15 to 20 mph with gusts to 30 mph increasing to 20 to 30 mph with gusts to 50 mph in the afternoon.
Snowfall expected in the next 24 hours: 0 inches
2 Day Mountain Weather Forecast:

7000 to 8000 Feet:
Today, sunny skies with daytime highs 48 to 56 deg. F. Southwest winds at 10 to 15 mph with gusts to 30 mph in the afternoon.

Tonight, mostly cloudy skies with overnight lows around 29 deg. F. Southwest winds at 10 to 20 mph with gusts to 35 mph decreasing to 25 mph after midnight.

For Tuesday, mostly cloudy skies with daytime highs 43 to 53 deg. F. Southwest winds at 10 to 15 mph increasing to 15 to 25 mph with gusts to 35 mph.

Above 8000 Feet:

Today, sunny skies with daytime highs 40 to 48 deg. F. Southwest winds at 15 to 20 mph with gusts to 30 mph increasing to 20 to 30 mph with gusts to 50 mph in the afternoon.

Tonight, mostly cloudy skies with overnight lows around 27 deg. F. Southwest winds at 20 to 30 mph with gusts to 50 mph decreasing to 25 mph after midnight.

For Tuesday, mostly cloudy skies with daytime highs 36 to 44 deg. F. West winds at 15 to 25 mph with gusts to 45 mph shifting to the southwest and increasing to 25 to 35 mph with gusts to 60 mph in the afternoon.

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