BACKCOUNTRY AVALANCHE FORECAST FOR THE OLYMPICS WASHINGTON CASCADES AND MT HOOD AREA NORTHWEST WEATHER AND AVALANCHE CENTER SEATTLE WASHINGTON 900 AM PST SAT FEB 7 2009 NWAC Program administered by: USDA-Forest Service with cooperative funding and support from: Washington State Department of Transportation National Weather Service National Park Service Washington State Parks and Recreation Commission Pacific Northwest Ski Area Association Friends of the Avalanche Center and other private organizations. This forecast applies to back country avalanche terrain below 7000 feet and does not apply to highways or operating ski areas. WAZ513-518-519-019-042-501-502-ORZ011-081700- && ZONE AVALANCHE FORECASTS * OLYMPICS- * WASHINGTON CASCADES NEAR AND WEST OF THE CREST- * STEVENS SNOQUALMIE WHITE PASSES- * EAST SLOPES WASHINGTON CASCADES- * MT HOOD AREA- Saturday and Sunday: Generally low avalanche danger below 7000 feet. Sunday night: Avalanche danger slightly increasing remaining generally low below 7000 feet. SNOWPACK ANALYSIS The last significant snowfall was back on about 28 January when about 6-12 inches of snow was seen near and west of the crest. Some light amounts of snow and some mild periods have been seen since that time. Trace or 1 inch amounts of new snow are reported Saturday morning along with some drizzle at Snoqualmie on Friday. This weather should have caused the snow pack in most areas to stabilize. Some good spring like conditions have been reported the past couple days on some south facing slopes such as on the Turns All Year web site. Conditions on north slopes mostly seem quite varied with some lingering shallow loose cold surface snow, or surface crusts, or hard rough skiing, or hard rough surfaces or avalanche debris. A back country skier on Turns All Year reported some surviving surface powder and some sluffs in the Mt Baker area the past 2 days. A general expected upper snow pack structure on south slopes seems to be fairly homogenous firm or hard melt freeze or equi-temperature snow. A general expected upper snow pack structure on north slopes might be more varied where one might find shallow crusts and colder snow from the past few days, over consolidated snow from late January, over harder snow from the inversion pattern of mid January. There are occasional reports of some facets lingering in the mid pack on north slopes. But these layers should generally be well protected by overlying thick firm snow or are dormant at this time. The last avalanches seem to be 2nd hand reports of 2 isolated triggered avalanches on north slopes reported on the FOAC Info Exchange from 2 and 3 February near Washington and Stevens Passes. DETAILED FORECASTS SATURDAY AND SATURDAY NIGHT Light winds and sunny warmer weather is expected Saturday. This should cause little change in generally stable snow conditions. Use normal caution on Saturday. Shallow surface softening or melting may occur on south slopes. This should cause some good spring like conditions on south slopes. Use extra caution on any steep slope if soft warmed surface snow becomes deeper than a few inches. Mostly clear weather should be seen Saturday night. This should allow any shallow wet surface snow to refreeze to some extent. SUNDAY AND SUNDAY NIGHT Light winds and fair weather should continue Sunday morning. Increasing high clouds should be seen by Sunday afternoon in the Olympics and Cascades. This should cause little change in overall stable snow conditions and a low avalanche danger. Shallow surface softening or melting may occur on south slopes so some more good spring like conditions may be seen on these aspects. Remember to use extra caution on any steep slope if soft warmed surface snow becomes deeper than a few inches. The next splitting weather system should move to the area Sunday night to Monday morning. This should cause increasing southeast to southwest crest level winds, increasing mostly light snow and lowering snow levels. Snow amounts should be light at most sites so a significant changes or a significant increase in the avalanche danger is not expected. Remember this is a regional forecast and to do your own on site assessments especially if you find your self in an area where more than a few inches of snow accumulates Sunday night and Monday morning. Backcountry travelers should be aware that elevation and geographic distinctions are approximate and that a transition zone between dangers exists. Remember there are avalanche safe areas in the mountains during all levels of avalanche danger. Contact local authorities in your area of interest for further information. NWAC weather data and forecasts are also available by calling 206-526-6677 for Washington, 503-808-2400 for the Mt Hood area, or by visiting our Web site at www.nwac.us. Also note that field snowpack information is often available on the FOAC website at www.avalanchenw.org, and weather and avalanche glossaries for commonly used terms in the forecasts can be found on the NWAC education page. Ferber/Northwest Weather and Avalanche Center $$