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 January 15, 2008 6:41 AM
Click here for a detailed map of the SAC forecast area

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Today's Advisory:

Avalanche danger is LOW for all elevations and aspects. Normal caution is advised.

An air temperature inversion remains in place over the forecast area this morning. Despite warmer air temperatures at the upper elevations than on the valley floor, areas above 8,000' have experienced several hours of below freezing temperatures overnight. Moderate west winds this morning are expected to mix the lower atmosphere and break down the inversion. As a cold front passes to the north and east of our area today, ridgetop winds are expected to shift to the northwest in the afternoon. This cold front is expected to bring the possibility of upslope snow showers to the forecast area tonight.

Yesterday, warm air temperatures at all elevations melted surface snow in the vast majority of areas. Slopes that have not yet undergone snow surface melting remain on N-NW aspects above 9,000'. Snowpack observations gathered over the past few days from Relay Peak (Mount Rose area), Castle Peak (Donner Summit area), Ellis Peak (Homewood area), and near Kirkwood Resort (Carson Pass area) all indicate a stable snowpack at this time. While warm air temperatures have melted surface snow in many locations, the snowpack remains dry below the top 1-2 inches of the snowpack. With increased cloud cover and slightly cooler air temperatures forecast for today, the threat of warming instability in the snowpack is minimal.

Widespread melt-freeze snow surface conditions exist in most areas. Above 9,000', enjoyable unconsolidated snow surface conditions exist on N-NW aspects, especially in wind protected areas. Wind scoured surfaces are found on many high elevation NE-E aspects at this time.

The bottom line: Avalanche danger is LOW for all elevations and aspects. Normal caution is advised.
Please send us your snow, weather, and avalanche observations by clicking the submit observations link on our contact page.

Brandon Schwartz, Avalanche Forecaster

Today's Central Sierra Weather Observations:
0600 temperature at Sierra Crest (8,700 feet): 28 deg. F
Max. temperature at Sierra Crest past 24 hours: 39 deg. F
Average wind direction at Sierra Crest past 24 hours: West
Average wind speed at Sierra Crest past 24 hours: 27 mph
Maximum wind gust at Sierra Crest past 24 hours: 45 mph
New snow fall at 8,200 feet past 24 hours: 0 inches
Total snow depth at 8,200 feet: 56 inches

Mountain Weather Forecast For Today:
Partly cloudy skies.
Temperature forecast for 8,000 to 9,000 feet: 37 to 40 deg. F
Ridgetop winds forecast for the Sierra Crest: West at 20 to 25 mph with gusts to 40 mph, becoming northwest 10 to 15 mph with gusts to 35 mph in the afternoon.
Snowfall expected in the next 24 hours: Trace to 1 inch

2 Day Mountain Weather Forecast:

7000 to 8000 Feet:
Today, partly cloudy skies with daytime highs around 39 deg. F. Northwest winds at 10 to 20 mph with gusts to 35 mph in the morning.

Tonight, mostly cloudy skies with isolated snow showers. Overnight lows 14 to 20 deg. F. Northeast winds at 10 to 20 mph with gusts to 30 mph.

For Wednesday, mostly cloudy skies with a slight chance of snow showers in the morning. Daytime highs around 32 deg. F. East winds at 10 to 20 mph with gust to 30 mph, increasing to 15 to 25 mph with gusts to 40 mph in the afternoon.

Above 8000 Feet:
Today, partly cloudy skies with daytime highs around 39 deg. F. West winds at 20 to 25 mph with gusts to 40 mph. Northwest winds at 10 to 15 mph with gusts to 30 mph in the afternoon.

Tonight, mostly cloudy skies with isolated snow showers. Overnight lows 16 to 22 deg. F. North winds at 20 to 25 mph with gusts to 40 mph.

For Wednesday, mostly cloudy skies with a slight chance of snow showers in the morning. Daytime highs around 31 deg. F. Northeast winds at 20 to 30 mph with gusts to 45 mph, increasing to 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:
	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.