Avalanche Forecast

A weak upper ridge should move across the area Wednesday, causing further clearing with little change in freezing levels.  However, solar effects should cause significant daytime warming.  This should again lead to mainly wet snow avalanche concerns.  

As the older storm slab and wind slab layers continue to settle and stabilize Wednesday, the main concern should be mainly wet loose avalanches on steep sun exposed terrain. This should be likely on solar slopes in all three elevations bands and may be also possible on non-solar slopes. Watch for wet surface snow deeper than a few inches, roller balls in surface snow and small natural wet loose releases that usually precede more major wet loose snow avalanches. Avoid terrain traps where a small but powerful wet loose avalanche could have unintended consequences.

Continue to watch for areas of recent wind slab on lee slopes. This is likely on shaded north to east slopes near and above treeline. Watch for signs of cracking or firmer wind transported snow and approach open lee slopes with caution.

Remember to watch for cornices if you venture onto ridges Wednesday and avoid slopes below cornices. Cornice failures are often seen during the transition to spring weather.

A wintery weather pattern was renewed over the Northwest starting last Tuesday lasting until Sunday midday. About 2 feet of snow fell at Hurricane between last Tuesday and Sunday with less snow at lower elevations.

Avalanche conditions also became active through the weekend.  We are now seeing a mix of winter snow conditions mainly on shaded slopes at higher elevations and spring snow conditions on solar slopes and at lower elevations. 

A frontal system passing through on Friday brought moderate south winds and wet snowfall at Hurricane Ridge, with rain likely not far below in elevation. NWAC observer Katy Reid at Hurricane on Friday reported local wind slab along along lee ridges with pit tests giving stubborn but clean shears. She also found some storm snow instabilities giving clean results in hand tests at about 15 cm or 6" below the surface.

By Sunday, additional new snow at slightly colder temperatures was creating additional storm and wind slab concerns, especially with the effects of strong solar input at times.

The Park ranger at Hurricane Tuesday morning reported widespread but shallow loose wet slides that released during warming Monday.

Little or no new snow has fallen since Sunday with periods of sunshine and temperatures in the low 40's allowing storm weaknesses to quickly settle and stabilize.  While we have been in a stabilizing pattern going on three days come Wednesday, making human triggered slides much less likely, there still may be some unstable wind slab or storm slab conditions remaining, especially higher elevation shaded slopes where stabilization has been slower. Continue to choose conservative terrain, watching for previous wind deposits.     

Wind slab cracking from ski at Hurricane Ridge, Near Tree Line, Sunday 3/30 by NWAC observer Katy Reid.

Natural wind slab avalanches likely from Saturday were found at Hurricane by Katy on Sunday with several releases up to size 2 mainly 6-12 inches but stepping up to 2.5 feet on a north slope. Tests indicated a clean interface at about 20 cm in the storm snow.

Natural wind slab avalanches found at Hurricane on Sunday by NWAC observer Katy Reid.