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 9, 2008:


April 9, 2008 at 0:00 am

Forecast Discussion:


This advisory was posted on April 9, 2008 6:50 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.

The weather system that passed through the forecast area yesterday has moved off to the east. High pressure has built in over the region and skies are clear this morning. New snow amounts from the past 24 hours are minimal, ranging from a trace to 1 inch of accumulation. Ridgetop winds shifted to the north overnight and have decreased to light in speed this morning. Winds are forecast to shift to northwest and increase to moderate speed as the day progresses. Remote sensors report air temperatures well below freezing at all locations within the forecast area this morning.

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 southerly aspects, the snowpack is well adjusted to the near daily melt-freeze conditions that have occurred over the past 6 weeks. On northerly aspects, snow surface conditions are a mix of frozen melt-freeze crust and wind scoured areas. High density, well bonded snow layers exist below the surface. Some small and isolated pockets of shallow unconsolidated snow linger on north aspects at the upper elevations.

Today, sunny skies and significant solar radiation will cause melting of surface snow in sun exposed areas, especially below 8,500'. Wet snow that forms in response to daytime warming is expected to remain limited to the top 1 to 2 inches of the snowpack. The amount of surface snow melting that occurs today is not expected to lead to wet snow instability. Natural and human triggered avalanches remain unlikely at this time.

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

Brandon Schwartz, Avalanche Forecaster

Today's Central Sierra Weather Observations:
0600 temperature at Sierra Crest (8,700 feet): 13 deg. F
Max. temperature at Sierra Crest past 24 hours: 26 deg. F.
Average wind direction at Sierra Crest past 24 hours: Southwest shifting to north
Average wind speed at Sierra Crest past 24 hours: 23 mph
Maximum wind gust at Sierra Crest past 24 hours: 57 mph
New snowfall at 8,200 feet past 24 hours: trace to 1 inch
Total snow depth at 8,200 feet: 75 inches

Mountain Weather Forecast For Today:
Sunny skies.
Temperature forecast for 8,000 to 9,000 feet: 23 to 33 deg. F
Ridgetop winds forecast for the Sierra Crest: Northwest at 10 to 20 mph with gusts to 40 mph.
Snowfall expected in the next 24 hours: 0 inches

2 Day Mountain Weather Forecast:

7000 to 8000 Feet:

Today, partly cloudy skies with daytime highs 33 to 43 deg. F. Northwest winds at 10 to 15 mph.

Tonight, clear skies with overnight lows 26 to 36 deg. F. Northwest winds at 10 to 15 mph shifting to north after midnight.

For Thursday, sunny skies with daytime highs 43 to 53 deg. F. Light winds becoming north around 10 mph in the afternoon.

Above 8000 Feet:

Today, partly cloudy skies with daytime highs 23 to 33 deg. F. Northwest winds at 10 to 20 mph with gusts to 40 mph.

Tonight, clear skies with overnight lows 20 to 30 deg. F. North winds at 10 to 15 mph with gusts to 30 mph.

For Thursday, sunny skies with daytime highs 35 to 45 deg. F. North winds around 10 mph with gusts to 25 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:

  Wednesday: Wednesday Night: Thursday:
Weather:
Temperatures: deg. F. deg. F. deg. F.
Wind direction:
Wind speed:
Expected snowfall: O in. O in. O in.

For 8000-9000 ft:

  Wednesday: Wednesday Night: Thursday:
Weather:
Temperatures: deg. F. deg. F. deg. F.
Wind direction:
Wind speed:
Expected snowfall: O in. O in. O in.