Avalanche Forecast

An upper ridge should drift across the Northwest on Friday. In the Olympics and Cascades this should cause some high clouds, light winds and gradually moderating temperatures west of the crest and at higher elevations.

Recent wind slabs should be primarily on N-W-S aspects. The benign weather should bring a little more stabilizing to these layers on Friday. Remember that firmer wind transported snow is always your best sign of wind slab layers.

The wind slab compass indicator below shows loading for the recent dominant wind direction but some areas may have experienced other loading patterns, so be alert on all terrain aspects for firmer wind transported snow.

Small loose dry avalanches might be possible in steep wind sheltered terrain but will not be listed as an avalanche problem. 

Weather and Snowpack

A pair of warm fronts moved across the Northwest Saturday and Sunday causing see-sawing temperatures to near or above freezing for areas away from the Passes with milder Pacific air finally dislodging colder air in the Passes late Sunday night. 5-10 inches of snow fell through Monday morning with snow showers depositing another 5 inches in the Mt. Baker area through Monday afternoon.

A weak low pressure system, tracking across southern Washington Tuesday morning through Wednesday afternoon, deposited another 3-6 inches of snow with light winds from Stevens Pass and southward, with Paradise adding another 12 inches. A period of strong E to NE winds increased Tuesday afternoon through early Wednesday before diminishing Wednesday afternoon. 

Recent Observations

NWAC pro-observer Dallas Glass was in the Kendall Peak area below treeline Tuesday. Dallas found the new snow generally right side-up with good snow conditions. A freezing rain or rain crust at 25 cm was ski supportable. The crust disappeared above 4800 feet. The only direct signs of instability noted, were small loose dry sluffs on steeper slopes. Coming home via the highway, strong east wind were beginning to transport snow on Granite Mountain by mid-afternoon. 

NWAC pro-observers Dallas and Ian Nicholson were back in the Crystal backcountry Wednesday to assess the distribution and sensitivity of fresh wind slabs from recent strong E-NE winds.  They found that wind slabs were becoming larger as they moved into the near tree line band and exposed ridges. NE-E-SE facing slopes were stripped of recent snow with new reactive wind slabs on N-W-S facing terrain and cross loaded features. Their travel in this area was therefore conservative. In wind sheltered terrain below treeline, the storm snow was right side up and lacked slab structure with excellent skiing conditions.

A couple worthwhile reports are available via the NWAC Observations page. A skier on Mt Herman near Mt Baker triggered a 12 inch wind slab on a W slope near some shallowly buried rocks on Wednesday. Skiers in the N facing Slot Couloir on Mt Snoqualmie on Wednesday reported reactive layers stepping down to 30-45 cm. Snow was less reactive on S slopes.