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 15, 2008 6:27 AM

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

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Today's Advisory:

Near and above treeline, avalanche danger is MODERATE with pockets of CONSIDERABLE danger on wind loaded N-NE-E aspects, 37 degrees and steeper. Below treeline, avalanche danger is LOW with pockets of MODERATE danger in open areas 37 degrees and steeper.

A storm system moved through the forecast area last night, creating snow showers that were heavy at times. Snowfall has tapered off this morning, but snow shower activity is expected to continue through the day today. New snowfall amounts for the last 24 hours range from 8 to 12 inches along the Sierra Crest and around 5 inches in the Mount Rose area. The snow study plot at Kirkwood Ski Area is reporting overnight new snow density of 8% decreasing to 4%. Storm totals for the past two days range from 10 to 17 inches. The air temperature trend has gone from warm to cold during this storm. Ridgetop winds have remained from the southwest for the past several days. Wind speed increased from moderate to strong overnight and has decreased to moderate this morning. Winds are expected to shift to the west this morning, then shift and decrease to light north this afternoon. A slight chance of thunderstorms exists for this afternoon.

Yesterday, light snow shower activity continued off and on throughout the day, but significant new snow accumulation did not begin until late afternoon. Observations made on Jakes Peak (West Shore Tahoe area) indicated that the previously rain affected snow surface had refrozen. Some wet snow remained below the near surface crust in the 7,000' to 8,000' elevation range. Up to 4 inches of new snow was well bonded to the top of the rain crust. Above treeline, shallow slabs had formed in wind loaded areas on N-NE-E aspects. Skier loading of test slopes above treeline was unable to create surface slab failure. In the Mount Rose area, recent reports of poor bonding of new snow to the old snow surface have been received.

Today, new snow overnight combined with moderate to strong southwest winds has created fresh slabs in wind loaded areas, mainly near and above treeline on N-NE-E aspects. Continued snow shower activity and shifting winds will cause areas of snowpack instability to persist today. Human triggered slab avalanches are possible to probable in steep wind loaded areas. Isolated natural slab avalanche activity is possible today. Human triggered loose snow avalanches are possible in steep wind protected areas.

The bottom line: Near and above treeline, avalanche danger is MODERATE with pockets of CONSIDERABLE danger on wind loaded N-NE-E aspects, 37 degrees and steeper. Below treeline, avalanche danger is LOW with pockets of MODERATE danger in open areas 38 degrees and steeper.

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): 12 deg. F
Max. temperature at Sierra Crest past 24 hours: 23 deg. F.
Average wind direction at Sierra Crest past 24 hours: Southwest
Average wind speed at Sierra Crest past 24 hours: 44 mph.
Maximum wind gust at Sierra Crest past 24 hours: 99 mph
New snowfall at 8,200 feet past 24 hours: 5 to 12 inches
Total snow depth at 8,200 feet: 90 inches

Mountain Weather Forecast For Today:
Cloudy with snow showers. A slight chance of thunderstorms in the afternoon.
Temperature forecast for 8,000 to 9,000 feet: 15 to 21 deg. F
Ridgetop winds forecast for the Sierra Crest: West at 15 to 25 mph with gusts to 50 mph. Winds shifting to north at 10 to 20 mph in the afternoon.
Snowfall expected in the next 24 hours: 4 to 8 inches

2 Day Mountain Weather Forecast:

7000 to 8000 Feet:
Today, cloudy skies with snow showers and a slight chance of thunderstorms in the afternoon. Snow accumulation 3 to 6 inches. Daytime highs 21 to 28 deg. F. West winds at 10 to 15 mph shifting to the north in the afternoon.

Tonight, cloudy skies with snow showers in the evening, then scatted snow showers overnight. Snow accumulation 1 to 2 inches. Overnight lows around 15 deg. F. Northeast winds at 10 to 20 mph.

For Sunday, partly cloudy skies with a chance of snow showers mainly over Alpine County. Daytime highs 22 to 30 deg. F. Northeast winds at 10 to 20 mph with gusts to 30 mph.

Above 8000 Feet:
Today, cloudy skies with snow showers and a slight chance of thunderstorms in the afternoon. Snow accumulation 3 to 6 inches. Daytime highs 15 to 21 deg. F. West winds at 15 to 25 mph with gusts to 50 mph. Winds shifting to north at 10 to 20 mph in the afternoon.

Tonight, cloudy skies with snow showers in the evening, then scatted snow showers overnight. Snow accumulation 1 to 2 inches. Overnight lows around 10 deg. F. North winds at 15 to 25 mph with gusts to 45 mph.

For Sunday, partly cloudy skies with a chance of snow showers mainly over Alpine County. Daytime highs 17 to 23 deg. F. Northeast winds at 20 to 30 mph with gusts to 50 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:
	Saturday:	Saturday Night:	Sunday:
Weather:
Temperatures:	deg. F.	deg. F.	deg. F.
Wind direction:
Wind speed:
Expected snowfall:	O in.	O in.	O in.
For 8000-9000 ft:
	Saturday:	Saturday Night:	Sunday:
Weather:
Temperatures:	deg. F.	deg. F.	deg. F.
Wind direction:
Wind speed:
Expected snowfall:	O in.	O in.	O in.