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 February 26, 2008 6:53 AM
Click here for a detailed map of the SAC forecast area

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Today's Advisory:

Areas of MODERATE avalanche danger are expected at all elevations on E-SE-S-SW aspects 37 degrees and steeper in response to warm air temperatures. On northerly aspects, LOW avalanche danger is expected.

An air temperature inversion is in place over most of the northern half of the forecast area this morning. Many remote sensors above 8,000' are reporting air temperatures in the upper 30s to low 40s prior to sunrise this morning. In the portion of the forecast area south of Lake Tahoe, no air temperature inversion has been observed this morning. Air temperatures warming into the 40s are forecast for all elevations today. Ridgetop winds have been light from the east over the past 24 hours.

Yesterday, continued settlement and increasing layer bond strength were observed within the recent storm snow. Snowpit observations from Jake's Peak (West Shore Tahoe area) taken below treeline at 7,600' on a ENE aspect showed that the density inversion that existed within the storm snow on Sunday had settled out of the snowpack. Layer bonding tests continued to yield moderate force shears, but no evidence of fracture propagation was observed. Small natural point releases and roller ball activity were observed in a variety of locations beginning around mid day on sun exposed E-SE-S aspects below 8,000' as daytime warming occurred.

Today, warm air temperatures are expected to create areas of instability on E-SE-S-SW aspects at all elevations. Areas where a significant air temperature inversion is in place this morning will see instability form faster than areas to the south where air temperatures at all elevations have been well below freezing overnight. As warm temperatures and solar radiation create free water within the surface snow, human triggered avalanches will be possible today, especially in steep sun exposed areas.

The bottom line: Areas of MODERATE avalanche danger are expected at all elevations on E-SE-S-SW aspects 37 degrees and steeper in response to warm air temperatures. On northerly aspects, LOW avalanche danger is expected.

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): 23 to 43 deg. F
Max. temperature at Sierra Crest past 24 hours: 32 to 43 deg. F.
Average wind direction at Sierra Crest past 24 hours: East
Average wind speed at Sierra Crest past 24 hours: 11 mph
Maximum wind gust at Sierra Crest past 24 hours: 31 mph
New snow fall at 8,200 feet past 24 hours: 0 inches
Total snow depth at 8,200 feet: 105 inches

Mountain Weather Forecast For Today:
Sunny and warm.
Temperature forecast for 8,000 to 9,000 feet: 42 to 48 deg. F
Ridgetop winds forecast for the Sierra Crest: Southeast at 10 mph in the morning becoming light.
Snowfall expected in the next 24 hours: 0 inches

2 Day Mountain Weather Forecast:

7000 to 8000 Feet:
Today, sunny skies with daytime highs around 48 degrees deg. F. Light winds expected.

Tonight, partly cloudy skies with overnight lows 19 to 25 deg. F. Light winds expected.

For Wednesday, partly cloudy skies with daytime highs around 54 deg. F. West winds up to 10 mph.

Above 8000 Feet:
Today, sunny skies with daytime highs 42 to 48 deg. F. Southeast at 10 mph in the morning becoming light.

Tonight, partly cloudy skies with overnight lows 22 to 30 deg. F. Light winds expected.

For Wednesday, partly cloudy skies with daytime highs around 51 deg. F. West winds at 10 to 15 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:
	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.