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 April 19, 2008 6:48 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 cold front is approaching the forecast area. Maximum daytime air temperatures for today are forecast at around 12 deg. F. colder than what was observed yesterday. Cloud cover is expected to increase late today, especially over the northern portion of the forecast area. Southwest ridgetop winds are expected to remain moderate to strong in speed into Sunday morning. Snow showers may occur over the far northern portion of the forecast area tonight. Remote sensors are reporting air temperatures this morning are at or below freezing above 8,000'. At locations below 8,000', air temperatures are in the mid to upper 30s.

Recent observations from around the forecast area indicated that melt-freeze conditions exist in all sun exposed areas. Any wet snow instabilities that have formed over the past week have been limited to very small human triggered wet snow sluffs. Layers deeper within the snowpack remain well bonded in all areas. Overnight, a combination of below freezing air temperatures at the upper elevations and good radiational cooling is expected to have refrozen the snow surface at all elevations.

Today, colder air temperatures will limit the amount of snow surface melting that occurs. The upper snowpack is expected to remain supportable throughout the day today. Any minor wet snow instabilities that occur will be very small and limited to human triggered sluff activity on very steep southerly aspects. Natural avalanche activity remains unlikely.

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): 28 to 32 deg. F
Max. temperature at Sierra Crest past 24 hours: 42 to 50 deg. F.
Average wind direction at Sierra Crest past 24 hours: Southwest
Average wind speed at Sierra Crest past 24 hours: 39 mph
Maximum wind gust at Sierra Crest past 24 hours: 63 mph
New snowfall at 8,200 feet past 24 hours: 0 inches
Total snow depth at 8,200 feet: 62 inches

Mountain Weather Forecast For Today:
Partly to mostly cloudy skies and cooler.
Temperature forecast for 8,000 to 9,000 feet: 33 to 41 deg. F
Ridgetop winds forecast for the Sierra Crest: Southwest 30 to 45 mph with gusts to 75 mph.
Snowfall expected in the next 24 hours: 0 to trace inches

2 Day Mountain Weather Forecast:

7000 to 8000 Feet:

Today, partly to mostly cloudy skies with daytime highs 39 to 47 deg. F. Southwest winds at 20 to 35 mph with gusts to 45 mph. Gusts increasing to 55 mph in the afternoon.

Tonight, mostly cloudy skies with a chance of snow showers. Overnight lows 13 to 19 deg. F. Southwest winds at 25 to 35 mph with gusts to 55 mph. Winds becoming west at 10 to 20 mph with gusts to 40 mph after midnight.

For Sunday, mostly cloudy skies with a slight chance of snow showers. Daytime highs 27 to 33 deg. F. West winds at 10 to 20 mph with gusts to 30 mph.

Above 8000 Feet:

Today, partly to mostly cloudy skies with daytime highs 33 to 41 deg. F. Southwest winds at 30 to 45 mph with gusts to 75 mph.

Tonight, mostly cloudy skies with a chance of snow showers. Overnight lows 9 to 17 deg. F. Southwest winds at 35 to 45 mph decreasing to 25 to 35 mph after midnight. Wind gusts up to 85 mph.

For Sunday, mostly cloudy skies with a slight chance of snow showers. Daytime highs 19 to 25 deg. F. West winds at 10 to 20 mph with gusts to 30 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:
	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.