Avalanche Forecast

Saturday

A brief break in precipitation is expected in most areas through early afternoon with gradual warming. Light precipitation at further warming expected later Saturday afternoon spreading from south to north. The warming temperatures Saturday should allow for any recent storm snow to continue to settle in place and stabilize. Only light amounts of precipitation are expected during daylight hours and should appreciably affect the avalanche danger.

Old wet snow conditions should persist, however, and maintain the potential for glide avalanches on steep unsupported terrain features that may not have released during the recent heavy rains. 

The old wet snowpack should continue to drain and stabilize and slowly re-freeze Saturday, especially at higher elevations. 

Watch for the numerous re-emerging ground hazards, such as open creeks, shallowly covered rocks and trees, creating poor and challenging travel conditions, especially below treeline.

Remember that closed ski areas without avalanche mitigation are equivalent to backcountry terrain!  

New resources within your Avalanche Forecast this season! 

The Mountain Weather tab will take you to the most recently issued Mountain Weather Forecast. The Observations & Weather Data tab will allow an easy view of the various weather station graphs within your zone of interest and provide easy access to the most recent avalanche and snowpack observations. 

The great start of winter 2017/18 in the PNW has taken a recent hit as warm wet weather arrived early Monday morning in the Mt Hood area and has just begun to cool as of late Thanksgiving. The Mt Hood weather stations received over 5 inches of rain since Monday morning, reaching well above the Cascade crest level.

No recent avalanche observations have been received from the Mt Hood area, however the warming and rain initially triggered numerous wet snow and glide avalanches earlier this week in the WA Cascades, mostly reported on Tuesday and Wednesday, especially on steep unsupported slopes and rock faces where many glide avalanches released. 

Rain has now melted significant snow with average snow depths decreasing about 50-60% since Monday! This has allowed much of the previously well snow covered terrain to open with many creeks and snow bridges re-appearing, especially near and below treeline. 

The wet or saturated snowpack continues to drain and as of Friday afternoon is beginning to solidify and begin slowly re-freezing.

Cooling since Thursday with additional, mostly light precipitation, has begun to add some new snow above the old wet snowpack. Very shallow new snow, generally less than 2 inches had accumulated as of Friday afternoon.

Observations

No direct snowpack or avalanche observations have been received in the Mt Hood area, however, similar conditions to the WA Cascades are expected and some recent observations are offered below.

A few NWAC observers began assessing the post deluge Friday, Nov 24, both in the Mt Baker and Alpental Valley backcountry. 

In the Baker region, the key take away is just how much the snow cover has diminished with travel becoming significantly more challenging and hazardous due to open creeks and shallow snow. Most of the observed recent wet snow or glide avalanches were estimated to be two or more days old. The most recent storm snow, up to about 6 inches, was reluctant to release on steep test slopes with storm layers appearing to rapidly settle with near freezing temperatures. No direct observations were made above treeline. 

In the Alpental Valley, a similar story is told with evidence of numerous glide avalanche releases from steep unsupported terrain and rock faces. Travel conditions, especially below treeline, are now difficult with numerous early season challenges and hazards having quickly returned.