Avalanche Forecast

Becoming cloudy Saturday with occasional light snow, mainly during the afternoon. Only light amounts of new snow are expected through the day Saturday. Winds should be mostly southerly and light to moderate. 

Strong to locally very strong E-NE winds Tuesday night and Wednesday loaded unusual aspects and built wind slab in all elevation bands. These wind slabs continue to heal and bond, but the cold temperatures are slowing that process. 

Watch for lingering wind slabs and avoid terrain where even a small slab avalanche could have unintended consequences. Remember to watch for firmer wind transported snow on all slope aspects or cross loaded slopes, especially in areas with varied terrain and modified wind directions. 

By late Saturday afternoon, there may be shallow, fresh wind slabs forming on wind loaded terrain. A more rapid increase in danger can be expected if greater snowfall and stronger winds than expected occur.  

Weather and Snowpack

A low pressure system moved across western Washington on Saturday night, followed by cold Arctic air. NWAC stations in the Mt Hood area received about 5 inches of snowfall by Sunday morning with SW winds.

An unusual reverse orographic east flow caused snow mainly in the central to south Cascades Sunday afternoon and night. NWAC stations at Mt Hood had a shift to NE winds and another 10-12 inches of snow on Monday morning and further cooling as the Arctic air mass further moved into the Northwest.

Very strong E-NE winds changed the snowscape dramatically on Mt. Hood Tuesday night and Wednesday. Winds near treeline regularly gusted into the 50s and 60s, while the upper stations at Meadows and Timberline had multiple gusts to 100 mph. Winds were still strong, but starting to moderate Wednesday afternoon.

Sunny and relatively calm weather has been enjoyed Thursday and again Friday with moderating temperatures.

Recent Observations

The Mt Hood Meadows pro-patrol on Monday reported that the recent wind shift was moving snow to S-W slopes. On avalanche control on Monday morning sensitive 4-6 inch storm slabs were released by skis on most test slopes. Deeper storm slab to about 2 feet was expected in loaded areas which could release to the Solstice crust. The shift to NE winds as also building new local soft 8-24 inch wind slab on S-W slopes.

NWAC pro-observer Laura Green was on E-NE slopes on Elk Mountain on Monday and found minor wind transport in the above tree in the 4200-5400 foot range but no signs of instability.

No reports were received on Wednesday and fierce winds that kept the ski areas from running most of their lifts also likely prevented anyone from venturing into the near or above treeline on Mt. Hood. 

Laura was at the Mt Hood Meadows Ski Area on Thursday and again Friday, following some of the strongest winds experienced on Mt Hood for a very, very long time. Similar observations were recorded both Thursday and Friday, indicating a mix of wind sculpted conditions, ranging from deep hard slabs, likely 1-2 meters or more in depth as well as scoured slopes to crust layers, sastrugi, and a thin melt-freeze sun crust on many south aspects. These deep slabs are unlikely to be triggered by a solo traveler, however, more shallow wind slabs may be a different story. Settled and stable powder was found on wind sheltered terrain, where skiing conditions remained very nice.