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 22, 2008 6:12 AM

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

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Today's Advisory:
This morning, avalanche danger is LOW for all elevations and aspects. Areas of MODERATE danger will develop on sun exposed E-SE-S-SW-W aspects, 38 degrees and steeper in response to daytime warming.

High pressure is firmly in place over the forecast area this morning. Remote sensors report that air temperatures at all elevations have fallen below freezing overnight, but are around 10 degrees warmer than 24 hours ago. Ridgetop winds have shifted from west to east overnight and remain light to moderate in speed. Air temperatures are expected to warm a few degrees over the maximum daytime air temperatures observed yesterday.

Yesterday, observations made on the south side of Jakes Peak (West Shore Tahoe area) indicated that recent new snow has undergone sufficient melt-freeze to make it indistinguishable from the older snow below it in most sun exposed areas below 8,000'. Pockets of colder recent new snow linger on southerly aspects above 8,000' and on northerly aspects above 7,000'. Good bonding of the recent new snow to the crust below was observed in all areas. Below freezing air temperatures and clear skies are expected to have caused a solid refreeze of melted surface snow in all areas overnight.

Today, the cycle of melting surface snow will continue in sun exposed areas. With air temperatures at the upper elevations in the upper 20s this morning, melting of surface snow will occur faster today than what was observed yesterday. This will have the greatest impact on E-SE-S-SW-W aspects at all elevations. Wet snow instability that occurs today is expected to involve only surface snow. The deeper snowpack remains well bonded with established melt water channels in place on southerly aspects. Melting of surface snow on higher elevation northerly aspects is not expected to cause wet snow instability at this time. Human triggered avalanches will become possible, especially late in the day on steep E-SE-S-SW-W aspects. Natural avalanche activity remains unlikely.

The bottom line: This morning, avalanche danger is LOW for all elevations and aspects. Areas of MODERATE danger will develop on sun exposed E-SE-S-SW-W aspects, 38 degrees and steeper in response to daytime warming.

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): 28 deg. F
Max. temperature at Sierra Crest past 24 hours: 38 to 45 deg. F.
Average wind direction at Sierra Crest past 24 hours: West shifting to east
Average wind speed at Sierra Crest past 24 hours: 14 mph
Maximum wind gust at Sierra Crest past 24 hours: 29 mph
New snowfall at 8,200 feet past 24 hours: 0 inches
Total snow depth at 8,200 feet: 83 inches

Mountain Weather Forecast For Today:
Sunny skies and warmer.
Temperature forecast for 8,000 to 9,000 feet: 41 to 49 deg. F
Ridgetop winds forecast for the Sierra Crest: East at 10 to 15 mph with gusts to 30 mph in the morning.
Snowfall expected in the next 24 hours: 0 inches

2 Day Mountain Weather Forecast:

7000 to 8000 Feet:
Today, sunny skies with daytime highs 49 to 55 deg. F. East winds at 10 to 15 mph with gusts to 25 mph in the morning.

Tonight, clear skies with overnight lows around 28 deg. F. Light winds expected.

For Sunday, sunny skies with daytime highs 51 to 57 deg. F. Southwest winds at 10 to 15 mph with gusts to 25 mph.

Above 8000 Feet:
Today, sunny skies with daytime highs 41 to 49 deg. F. East winds at 10 to 15 mph with gusts to 30 mph in the morning.

Tonight, clear skies with overnight lows around 29 deg. F. South winds up to 10 mph.

For Sunday, sunny skies with daytime highs 45 to 51 deg. F. Southwest winds at 10 to 15 mph with gusts to 25 mph. Winds increasing to 15 to 25 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:
	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.