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 Avalanche Advisory was published on April 6, 2008:


April 6, 2008 at 0:00 am

Forecast Discussion:


This advisory was posted on April 6, 2008 7:00 AM

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

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Today's Advisory:

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

A series of low pressure systems should move across the forecast area over the next few days. As the first of these systems moves through the area today, cloud cover and winds should increase and temperatures should decrease. This first system has very little moisture associated with it. Some small, isolated showers could occur tonight, but no significant accumulation is expected. Areas north of I-80 have the best chance for these showers.

Yesterday turned out to be a sunny spring day. Observations from the backcountry near Kirkwood and in the Mount Rose area indicated that the intense April sun did soften the refrozen snow surface on southerly, sun exposed slopes. These snow surfaces that softened yesterday should have undergone a solid refreeze last night due to some radiational cooling and below freezing air temperatures. Observations from across the forecast area continue to show a strong, well bonded snowpack below the surface layers at all elevations and on all aspects. On the southerly aspects this snowpack is capped by melt/freeze snow. On all other aspects a mix of frozen melt/freeze crusts, wind crusts, and wind scoured areas exists on the snow surface. Some isolated, small, shallow pockets of unconsolidated snow still exist on the most north facing slopes.

Today, increased cloud cover combined with cooler air temperatures should prevent most of the frozen snow surfaces from softening. Some of the most sun exposed SE-S-SW aspects could see some melting of the refrozen surface snow; however, this softening should be limited to the top few inches of snow. What little melting that does occur today should not be enough to create significant wet snow instabilities and avalanche activity will remain unlikely today.

The bottom line: Avalanche danger is LOW for all elevations and aspects. Normal caution is advised.

Andy Anderson, Avalanche Forecaster

Today's Central Sierra Weather Observations:
0600 temperature at Sierra Crest (8,700 feet): 23 deg. F
Max. temperature at Sierra Crest past 24 hours: 34-39 deg. F.
Average wind direction at Sierra Crest past 24 hours: Southwest
Average wind speed at Sierra Crest past 24 hours: 35 mph
Maximum wind gust at Sierra Crest past 24 hours: 52 mph
New snowfall at 8,200 feet past 24 hours: 0 inches
Total snow depth at 8,200 feet: 76 inches
Mountain Weather Forecast For Today:
Mostly cloudy and cooler.
Temperature forecast for 8,000 to 9,000 feet: 25 to 35 deg. F
Ridgetop winds forecast for the Sierra Crest: Southwest at 30 to 45 mph with gusts to 65 mph.
Snowfall expected in the next 24 hours: 0 inches
2 Day Mountain Weather Forecast:

7000 to 8000 Feet:

Today, mostly cloudy skies with daytime highs 35 to 45 deg. F. Southwest winds at 10 to 15 mph increasing to 15 to 25 mph with gusts to 40 mph this afternoon.

Tonight, mostly cloudy skies with a few isolated snow showers. Overnight lows 20 to 26 deg. F. Southwest winds at 15 to 25 mph with gusts to 40 mph decreasing to 10 to 15 mph with gusts to 30 mph after midnight.

For Monday, partly cloudy skies with daytime highs 34 to 44 deg. F. West winds at 10 to 15 mph.

Above 8000 Feet:

Today, mostly cloudy skies with daytime highs 25 to 35 deg. F. Southwest winds at 30 to 45 mph with gusts to 65 mph.

Tonight, mostly cloudy skies with a few isolated snow showers. Overnight lows 15 to 23 deg. F. Southwest winds at 20 to 35 mph with gusts to 65 mph decreasing to gusts to 45 mph after midnight.

For Monday, partly cloudy skies with daytime highs 27 to 37 deg. F. West winds at 20 to 30 mph decreasing to 10 to 15 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:

  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.