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 Friday, March 23nd, 2007 at 7:05 am

The bottom line: Avalanche danger is LOW for all elevations and aspects. As daytime warming occurs the avalanche danger will increase slightly but should remain in the LOW category. A few small, isolated pockets of wet snow instabilities may develop and should be limited to pinwheel and roller-ball activity and maybe a small wet loose sluff on SW-S-SE slopes 35 degrees and steeper that are exposed to the sun today. Most of these will be south of Highway 88 where more new snow accumulated.

High pressure has built back into the forecast area bringing sunny skies, warmer air temperatures, and northeasterly winds. As this system settled over the area yesterday ridgetop winds began to calm down and should continue to decrease through Saturday when a low pressure system should start pushing the high off to the east. The low should cause the winds to start shifting back to the southwest and increasing on Sunday before it fully arrives over the forecast area on Monday. A decent amount of precipitation is forecasted to travel with this storm. The bulk of this precipitation should arrive after the weekend, but some shower activity could begin occurring as early as Sunday.

After 2 days of colder weather the warmer air temperatures are gradually returning with daytime highs reaching into the mid 40's. Overnight lows have been below freezing and the skies have been clear allowing the snowpack to undergo a solid refreeze each night. These melt-freeze cycles will continue to increase the stability of the current snowpack. The new snow that fell earlier in the week is quickly changing to melt-freeze snow as the diurnal cycles occur. The melting phase of the current melt-freeze cycles is much less intense than it was last week due to more gradual warming, lower high temperatures, stronger refreezes, and a moderate east to northeast wind. Therefore the chance of wet snow instabilities should be less widespread and severe. In some isolated areas South of Hwy 88, where more new snow accumulated there may still be a small chance of isolated human triggered wet snow instabilities today in wind protected areas below treeline, especially in the 7,000' to 8,000' elevation range. These instabilities should be small, isolated and limited to pinwheel and roller-ball activity and maybe a small wet loose sluff on SW-S-SE slopes 35 degrees and steeper that are exposed to the sun today. In most other areas avalanche activity is unlikely today but not impossible. Any instabilities that do form today should from as a result of daytime warming on sun exposed SW-S-SE slopes. Remember to step off you equipment and check boot penetration in the snowpack. If boot penetration exceeds boot tops in wet snow it is time to move on away from that slope and slopes like it.

As the day warms up good corn conditions should develop on the sun exposed SW-S-SE-E aspects across the forecast area. There should be a good supportable base under the corn due to the solid refreezes. Remember to continually evaluate the conditions as they change over the course of the day and be willing to change plans accordingly.

The bottom line: Avalanche danger is LOW for all elevations and aspects. As daytime warming occurs the avalanche danger will increase slightly but should remain in the LOW category. A few small, isolated pockets of wet snow instabilities may develop and should be limited to pinwheel and roller-ball activity and maybe a small wet loose sluff on SW-S-SE slopes 35 degrees and steeper that are exposed to the sun today. Most of these will be south of Highway 88 where more new snow accumulated.

At this time, SAC is still short $1,700 in operating funds for this season and we have no money with which to start next season. Our next fundraiser is this Sunday, March 25th at Sugar Bowl Ski Area. We are selling $30 lift tickets that have been donated to us by Sugar Bowl. All proceeds from each ticket sale go directly to our operating budget. Tickets are only available online through Snowbomb.com. Tickets can be easily obtained up to the night before the event. Click here to purchase your lift ticket. Come on out and join us for wonderful day of spring sun on the deck, corn snow on the slopes, and a gear raffle from Backcountry Access, Black Diamond, and Patagonia. We are very appreciative of the financial support already received this winter from a variety of users. If you have not yet shown your financial support for us this winter, please do so!

Andy Anderson , Avalanche Forecaster
Today's Central Sierra Weather Observations:
0600 temperature at Sierra Crest (8,700 feet):
31 deg. F
Max. temperature at Sierra Crest past 24 hours:
45 deg. F
Average wind direction at Sierra Crest past 24 hours:
Easterly
Average wind speed at Sierra Crest past 24 hours:
25-35 mph
Maximum wind gust at Sierra Crest past 24 hours:
60 mph
New snow fall at 8,200 feet past 24 hours:
0 inches
Total snow depth at 8,200 feet:
67 inches
Mountain Weather Forecast For Today:
Sunny skies.
Temperature forecast for 8,000 to 9,000 feet:
39 to 44 degrees F.
Ridgetop winds forecast for the Sierra Crest:
Northeasterly 20-30 mph decreasing in the afternoon.
Snowfall expected in the next 24 hours:
0 inches
2 Day Mountain Weather Forecast:

7000 to 8000 Feet:
Today, sunny skies with daytime highs 43 to 49 degrees F. Northeast winds at 10 to 15 mph. Tonight, clear skies with overnight lows 30 to 37 degrees F. East winds at 5 to 10 mph. Tomorrow, partly cloudy skies with daytime highs 46 to 52 degrees F. West winds at 10 to 15 mph are expected.

Above 8000 Feet:
Today, sunny skies with daytime highs 39 to 44 degrees F. Northeast winds at 20-30 mph decreasing in the afternoon. Tonight, clear skies with overnight lows 28 to 34 degrees F. East winds at 15 to 20 mph. Tomorrow, partly cloudy skies with daytime highs 42 to 47 degrees F. West winds at 10 to 20 mph with gusts to 30 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:
	Friday:	Friday Night:	Saturday:
Weather:
Temperatures:	deg. F.	deg. F.	deg. F.
Wind direction:
Wind speed:
Expected snowfall:	O in.	O in.	O in.
For 8000-9000 ft:
	Friday:	Friday Night:	Saturday:
Weather:
Temperatures:	deg. F.	deg. F.	deg. F.
Wind direction:
Wind speed:
Expected snowfall:	O in.	O in.	O in.