Avalanche Forecast

You can still trigger a Wind Slab on northerly aspects at Hurricane Ridge on Sunday. Several inches of moist new snow expected to fall Friday night with generally light winds will disguise older, healing wind slabs formed during the Wednesday through Friday night time-frames.  You can use visual clues to identify wind loaded slopes. Blowing snow, snow drifts, and fresh cornices all indicate that wind slabs may exist in nearby terrain. Avoid slopes greater than 35 degrees where you see wind loading has occurred.

Expect Loose Wet avalanche problems to extend into near treeline or above treeline terrain on southerly aspects if the sun makes an appearance on Sunday. In this case, keep your slope angle down or avoid slopes where roller-balls are forming. At lower elevations, rain has saturated snow near the surface and without radiation cooling due to cloudy skies on Saturday night, the cooler air mass coming in may not be sufficient to consolidate the moist upper snowpack. Where you encounter active rainfall or wet snow surface conditions  indicated by roller balls or fan-shaped avalanche debris, stay off of slopes greater than 35 degrees. Loose Wet avalanches have the ability to entrain more snow than you might expect and may carry you into areas with higher consequences, such as trees, creeks or gullies.

Other spring hazards exist in the mountains. As water drains the snowpack, Glide avalanches are possible on slopes with smooth ground surfaces. Minimize your exposure to slopes with crevasse-like glide cracks. Glide avalanches are difficult to predict and can occur without warning.

Recent warm weather and rain resulted in many creeks beginning to open. Be cautious if your intended route takes you over larger creeks as snow bridges may have grown thin and weak.

Wet snow is falling Saturday afternoon with light winds at Hurricane ridge, following a break in the action Saturday morning.

At Hurricane ridge, 6.5" of new snow fell Friday night with over a foot of new snow accumulated since Wednesday. Moderate south winds Wednesday and again Thursday night through Friday night transported snow, likely forming wind slabs, particularly on northerly aspects.The snow has fallen at temperatures near freezing and has warmed with mid-day temperatures each of the last 3 days rising into the mid-30's at the weather station. The warm temperatures should have helped to quicken the stabilization of recently formed Wind Slabs formed primarily on northerly aspects. Observations indicate that the recent snow fell on an underlying strong and supportable crust.

The upper snowpack generally consist of layers of melt-form snow and strong rounded grains. This has produced a strong snowpack without any layers of concern.

Older weak snow had been observed on N-E aspects near and above treeline. Small facets were found just above a crust about 1.5 ft (45cm) below the snow surface. This interface is likely no longer an issue due to recent rain and warm temperatures. 

Observations

On Thursday NPS Rangers reported 6” (15cm) of heavy new snow over the most recent crust (4/11). The recently formed crust was strong and supportable.

On Friday 4/6, NWAC professional observer Matt Schonwald found glide cracks in isolated areas. The snowpack on solar aspects is becoming patchy, especially below treeline.