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 16, 2008 6:56 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 on wind loaded SE-S aspects, 37 degrees and steeper. Below treeline, avalanche danger is LOW with isolated pockets of MODERATE danger in open areas 40 degrees and steeper.

Isolated snow showers continue across the forecast area this morning. Storm snow totals from the past few days range from 10 to 17 inches in most areas. Cold air is in place over the region this morning with air temperatures between 7,000' and 10,000' in the teens to single digits. Ridgetop winds shifted to the north to northeast yesterday afternoon. Northeast to east ridgetop winds will continue today. Wind speed increased from light to moderate during the overnight hours and is forecast to remain moderate speed today.

Yesterday, light snow shower activity mixed with sun breaks occurred for most of the day. Observations made on Mount Lola (North of Donner Summit) revealed little to no slab formation in near and above treeline areas. New snow up to 34 inches deep in lee areas had a very uniform increase in density from top to bottom. Good bonding of new snow to the 3/13 rain crust was observed. Snowpit data taken above treeline on a 32 degree ENE aspect at 8,900' indicated that loose snow avalanche activity was more likely to occur than slab avalanche activity. Below treeline, a skier triggered sluff was observed on a 40 degree NE aspect at 8,600'. Snowmobile triggered sluffs were also reported on steep below treeline slopes by other travelers in the area. In the Kirkwood area, minimal slab formation and widespread human triggered sluff activity within the upper portion of the storm snow was reported. In the Mount Rose area, continued reports of poor bonding of new snow to the old snow surface have been received.

Today, northeast to east ridgetop winds will redistribute snow to lee areas on SE-S-SW-W aspects near and above treeline. Some wind scouring will occur on N-NE-E aspects, causing further stabilization of the snowpack in these areas. New wind loaded pockets are expected to have formed overnight in lee areas with continued wind loading expected today. Areas of instability are expected mainly on SE-S aspects above treeline. Human triggered avalanches remain possible in steep wind loaded areas. Small natural avalanches are unlikely but not impossible today, especially above treeline in the far northern portion of the forecast area. Isolated human triggered loose snow avalanche activity remains possible today below treeline in very steep open areas.

The bottom line: Near and above treeline, avalanche danger is MODERATE on wind loaded SE-S aspects, 37 degrees and steeper. Below treeline, avalanche danger is LOW with isolated pockets of MODERATE danger in open areas 40 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: West shifting to east
Average wind speed at Sierra Crest past 24 hours: 27 mph.
Maximum wind gust at Sierra Crest past 24 hours: 67 mph
New snowfall at 8,200 feet past 24 hours: trace to 2 inches
Total snow depth at 8,200 feet: 90 inches

Mountain Weather Forecast For Today:
Mostly cloudy with isolated snow showers.
Temperature forecast for 8,000 to 9,000 feet: 17 to 21 deg. F
Ridgetop winds forecast for the Sierra Crest: Northeast at 20 to 35 mph with gusts to 60 mph.
Snowfall expected in the next 24 hours: 0 to 1 inch

2 Day Mountain Weather Forecast:

7000 to 8000 Feet:
Today, mostly cloudy skies with isolated snow showers. Daytime highs 21 to 28 deg. F. Northeast winds at 10 to 15 mph, increasing to 15 to 25 mph with gusts to 35 mph in the afternoon.

Tonight, partly cloudy skies with overnight lows 14 to 19 deg. F. Northeast winds at 10 to 20 mph with gusts to 40 mph.

For Monday, partly cloudy skies with daytime highs 34 to 42 deg. F. East winds around 10 mph with gusts to 25 mph, shifting to the north in the afternoon.

Above 8000 Feet:
Today, mostly cloudy skies with isolated snow showers. Daytime highs 17 to 21 deg. F. Northeast winds at 20 to 35 mph with gusts to 60 mph.

Tonight, partly cloudy skies with overnight lows 13 to 18 deg. F. Northeast winds at 25 to 35 mph with gusts to 70 mph.

For Monday, partly cloudy skies with daytime highs 28 to 33 deg. F. Northeast winds at 20 to 25 mph with gusts to 40 mph. Winds shifting to the north at 10 to 15 mph with gusts to 40 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:
	Sunday:	Sunday Night:	Monday:
Weather:
Temperatures:	deg. F.	deg. F.	deg. F.
Wind direction:
Wind speed:
Expected snowfall:	O in.	O in.	O in.
For 8000-9000 ft:
	Sunday:	Sunday Night:	Monday:
Weather:
Temperatures:	deg. F.	deg. F.	deg. F.
Wind direction:
Wind speed:
Expected snowfall:	O in.	O in.	O in.