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 28, 2008 6:40 AM

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

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Today's Advisory:

Today, avalanche danger is LOW in the vast majority of areas for all elevations and aspects. Very isolated pockets of MODERATE danger may develop below 8,500' on E-SE-S aspects, 40 degrees and steeper in response to daytime warming.

Another cold front is on track to pass through the forecast area this afternoon and evening. Increasing cloud cover, strong winds, and isolated snow showers are expected today. Ridgetop winds have remained southwest for the past several days. Wind speed is beginning to increase this morning and is expected to become strong this afternoon. Remote sensors are reporting below freezing air temperatures this morning at all locations above 6,000'.

Yesterday, high thin cloud cover limited the amount of incoming solar radiation, slowing the melting of surface snow. Observations made on Silver Peak (North of Squaw) showed that only the top 1 inch of the snowpack had melted on E-SE aspects in sun exposed areas at 8,000' by noon. Areas where isolated shadows fell across sun exposed E-SE aspect slopes remained mostly frozen in this area at 1 pm. Overnight, below freezing air temperatures have allowed wet surface snow that formed yesterday to refreeze in all areas.

Today, some melting of surface snow will occur, mainly below 8,500' to 9,000'. Cloud cover and wind is expected to slow the melting of surface snow today, limiting any significant melting of surface snow to lower elevation E-SE-S aspects. Well established melt water pathways exist within the snowpack on E-SE-S-SW aspects. On northerly aspects, recent snowpit data indicates that free water percolation has been limited to the top 1 to 2 feet of the snowpack, well above any basal faceted layers. Instability deep within the snowpack remains unlikely at this time. Any areas of wet snow instability that occur today will be very isolated and limited in size. Some isolated human triggered wet loose avalanche activity may occur in sun exposed areas on very steep E-SE-S aspects below 8,500'. Natural avalanche activity remains unlikely.

The bottom line: Today, avalanche danger is LOW in the vast majority of areas for all elevations and aspects. Very isolated pockets of MODERATE danger may develop below 8,500' on E-SE-S aspects, 40 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.

Brandon Schwartz, Avalanche Forecaster

Today's Central Sierra Weather Observations:
0600 temperature at Sierra Crest (8,700 feet): 19 deg. F
Max. temperature at Sierra Crest past 24 hours: 34 to 40 deg. F.
Average wind direction at Sierra Crest past 24 hours: Southwest
Average wind speed at Sierra Crest past 24 hours: 22 mph
Maximum wind gust at Sierra Crest past 24 hours: 56 mph
New snowfall at 8,200 feet past 24 hours: 0 inches
Total snow depth at 8,200 feet: 78 inches

Mountain Weather Forecast For Today:
Mostly cloudy skies and windy with isolated snow showers.
Temperature forecast for 8,000 to 9,000 feet: 35 to 41 deg. F
Ridgetop winds forecast for the Sierra Crest: Southwest at 25 to 35 mph with gusts to 50 mph. Winds increasing to 40 to 50 mph with gusts to 90 mph in the afternoon.
Snowfall expected in the next 24 hours: trace to 2 inches

2 Day Mountain Weather Forecast:

7000 to 8000 Feet:
Today, mostly cloudy skies with isolated snow showers in the afternoon. Daytime highs 41 to 49 deg. F. Southwest winds at 20 to 30 mph with gusts to 35 mph. Gusts increasing to 50 mph in the afternoon.

Tonight, cloudy skies with scattered snow showers. Little or no snow accumulation. Overnight lows around 25 deg. F. Southwest winds 25 to 35 mph with gusts to 60 mph.

For Saturday, mostly cloudy skies with a slight chance of snow showers. Daytime highs 37 to 45 deg. F. Southwest winds around 10 mph.

Above 8000 Feet:
Today, mostly cloudy skies with isolated snow showers. Daytime highs 35 to 41 deg. F. Southwest winds at 25 to 35 mph with gusts to 50 mph. Winds increasing to 30 to 40 mph with gusts to 80 mph in the afternoon.

Tonight, cloudy skies with scattered snow showers. Snow accumulation up to 2 inches. Overnight lows around 21 deg. F. Southwest winds at 30 to 45 mph with gusts to 85 mph.

For Saturday, mostly cloudy skies with a slight chance of snow showers. Daytime highs 31 to 37 deg. F. Southwest winds at 20 to 30 mph with gusts to 40 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:
	Friday:	Friday Night:	Saturday:
Weather:
Temperatures:	deg. F.	deg. F.	deg. F.
Wind direction:
Wind speed:
Expected snowfall:	O in.	O in.	O in.
For 8000-9000 ft:
	Friday:	Friday Night:	Saturday:
Weather:
Temperatures:	deg. F.	deg. F.	deg. F.
Wind direction:
Wind speed:
Expected snowfall:	O in.	O in.	O in.