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 Sunday, January 7, 2007 at 6:50 am

Air temperatures are on the rise this morning and are expected to reach several degrees higher at the upper elevations than observed during the past few days. Interesting ridgetop winds this morning as the most of the Sierra Crest will experience easterly winds today, but higher elevation areas such as the Carson Range (Mount Rose) and Sierra Crest above 9,000' will experience northerly winds. A major cool down is expected to impact the forecast area beginning Tuesday night.

Yesterday's ridgetop winds were lower than expected, creating only small amounts of wind transport and minimal wind loading in lee areas. This allowed the snowpack to bond and stabilize. The snowpack above 8,000' along the Sierra Crest is now 5 to 6 feet deep and recovering nicely from the shallow early season with much rounding and sintering of snow crystals observed in many areas. Below 8,000' along the Sierra Crest and on northerly aspects in the Mount Rose area, a more shallow snowpack exists that is still plagued by strong temperature gradients and faceting processes within the snowpack. Recent winds have created areas of hard wind slab on the majority of aspects above treeline. These hard slabs are stable at this time, but normal caution should still be taken as an avalanche event is unlikely, but not impossible. Expose only one person at a time to steep slopes. Avoid trigger points such as slope convexities, areas near isolated rocks, single trees, and near cliff bands. Any areas where the snow near you sounds hollow should be avoided. Avoiding trigger points is the fine art of the uphill and the down hill line made by backcountry travelers. Very little snow remains available for wind transport. The creation on new areas of wind loading and instability are not expected to occur today, despite ridgetop winds that are strong enough to move snow. Wonderful, unconsolidated snow can still be found below treeline in wind protected areas.

Avalanche danger is LOW at all elevations and on all aspects at this time.

Brandon Schwartz, Avalanche Forecaster

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Today's Central Sierra Weather Observations:
0600 temperature at Sierra Crest (8,700 feet): 22 deg. F
Max. temperature at Sierra Crest past 24 hours: 30 deg. F
Average wind direction at Sierra Crest past 24 hours: westerly shifting to easterly
Average wind speed at Sierra Crest past 24 hours: 30 mph
Maximum wind gust at Sierra Crest past 24 hours: 59 mph
New snow fall at 8,200 feet past 24 hours: 0 inches
Total snow depth at 8,200 feet: 42 inches

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Mountain Weather Forecast For Today:
Mostly sunny skies
Temperature forecast for 8,000 to 9,000 feet: 35 - 45 degrees F.
Ridgetop winds forecast for the Sierra Crest: Northerly to easterly 30 - 40 mph, G 50 mph
Snowfall expected in the next 24 hours: 0 inches

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2 Day Mountain Weather Forecast:
7000 to 8000 Feet
For today, mostly sunny skies. Day time highs 38 to 48 degrees F. East winds 5 to 15 mph. Overnight, clear with lows 22 to 32 degrees F. East winds at 5 to 15 mph. Monday will be sunny with daytime highs 38 to 48 degrees F. East winds at 10 to 20 mph are expected.

Above 8000 Feet
For today, mostly sunny skies. Daytime highs 27 to 37 degrees F. North to east winds 30 to 40 mph with gusts to 50 mph. Overnight, clear with lows 25 to 35 degrees F. North to east winds at 25 to 35 mph. Monday will be sunny and with daytime highs 37 to 47 degrees F. Northeast winds at 15 to 25 mph are expected.

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.