Good evening, this is Sue Burak with the Eastern Sierra Avalanche Center. A BACKCOUNTRY AVALANCHE WARNING HAS BEEN ISSUED FOR THE EASTERN SIERRA BACKCOUNTRY FROM SONORA PASS TO MT. WHITNEY. TWO TO THREE FEET OF SNOW AND OVER 3 OF WATER HAVE ACCUMLATED IN THE LAST 12 HOURS. STRONG WINDS HAVE CREATED WIDESPREAD AREAS OF UNSTABLE SNOW AND WIND SLABS PARTICULARLY ON NORTH AND WEST SLOPES ABOVE 8,000 FEET. AVALANCHES ARE CERTAIN ON MOST ASPECTS AND SLOPE ANGLES GREATER THAN 30 DEGREES. AVALANCHES WILL BE LARGE AND DESTRUCTIVE. TRAVEL IN AVALANCHE TERRAIN SHOULD BE AVOIDED. STICK TO LOW ANGLE TERRAIN WELL AWAY FROM AVALANCHE PATH RUNOUTS. MOUNTAIN WEATHER Several feet of dense snow has fallen in the last 18 hours. The storm continues to dump snow at rates of 2-3 inches per hour in all mountain locations from Leavitt Lake to Cottonwood Pass. The National Weather Service forecasters in Reno assure me that another 27-33 inches will fall tonight into Saturday morning above 8,000 feet. The 7,000 ft elevation areas of Lee Vining, Crowley Lake and Toms Place could see another 12-18 inches. Bishop was drenched with 3.5 of rain in the last 18 hours. Highs today will be in the mid 20s at most mountain locations with lows dropping to the teens Saturday night as a cold front moves through the area. Snow levels will fall to the Owens Valley floor Sunday. The blizzard warning is in effect until 10 AM Saturday morning. Winds will diminish tonight from the 80-100 mph range to a more reasonable 60-80 mph. The highest wind gust today was 132 mph at the top of Mammoth Mountain. Snowfall rates will calm down tomorrow but another storm moves into the area Saturday night. Expect snowfall Sunday with diminishing snowfall by Sunday afternoon. SNOWPACK AND AVALANCHE DISCUSSION Amazing snowfall and precipitation rates are the story of the day. NWS estimates of 2-3 per hour have verified at most backcountry sensors. Hurricane force winds did not occur. However, in the past 24 hours, wind speeds have been consistently ripping at 50-80 mph. Wind directions have been pegged at SW and ESE. The storm certainly does compare favorably with the Jan 10-17 2005 storm, except we may get 10 of water in 2 days instead of a week. It really is foolish to think about skiing anywhere except Mammoth Mountain. You will certainly trigger an avalanche if you venture out onto a wind loaded slope. With the amount of new snow and wind that has accumulated, avalanches will be large and deep. Imagine trying to find and shovel out your buddy buried under the heavy dense snow we have been shoveling all day. BOTTOM LINE BOTTOM LINE: Avalanche danger is EXTREME on all aspects above 8,000 feet. Widespread and large natural avalanches are certain. Human triggered avalanches are certain. Avalanche terrain and runout zones should be avoided. Please note that the avalanche danger rating in this advisory expires in 24 hours. This advisory is our best interpretation of snow pack conditions and NWS forecasts issued today. Backcountry travelers should be aware that elevation and geographic distinctions are approximate and that a transition zone exists between upper and lower elevations. Avalanches do not happen by accident and most human involvement is a matter of choice not chance. Most avalanche accidents are caused by slab avalanches that are triggered by the victim of member of the victim's party. Even small slides can be dangerous. Always practice route finding skills and carry avalanche rescue gear. Remember that avalanche danger ratings are only general guidelines. Distinctions between geographic areas, elevations, slope aspects and slope angles should be made.