Washington Terrain Ratings

Well -- I don't quite agree with the criteria for assigning the risk of the back bowl approach route. Yes the Paradise Valley road crosses some slopes with very high avalanche potential -- cliffy even.

However 90+% incidents are skiier triggered and a skiier is far less likely to trigger a release skiing on the roadbed itself. So assigning this degree of risk seems overly conservative to me.

I think it is important to risk assements and warnings reflect real world conditions and not be excessively conservative -- lest skiiers discount them.

However 90+% incidents are skiier triggered and a skiier is far less likely to trigger a release skiing on the roadbed itself. So assigning this degree of risk seems overly conservative to me.

I've updated the ratings here:

avalanchesafety.blogspot.com/2010/02/was...terrain-ratings.html

I moved the Mazama listing to "challenging".

The ATES rating system was developed in response to the Strathcona-Tweedsmuir avalanche in 2003. This avalanche released on the north side of Cheops and descended into Connaught Valley where it engulfed a party of high school students and their teachers. This tragedy was an extremely rare mix of timing and bad luck, but the degree of exposure was poorly understood by the teachers who planned the trip.

An objective view of exposure has to include a variety of sizes and types of avalanches, including unexpected natural releases.

Can anyone here suggest some more "Simple" and "Challenging" routes that are actually fun?

Thanks -- at some point it would be useful to provide more detail about the routes being rated.

For example:

"Narada Falls to Reflection Lakes" is listed as "Simple".

I agree with this when following the marked route over Inspiration Saddle.

However a fairly large number of people skin/snowshoe/hike directly up the open slope above the Narada falls comfort station (walking right past the "Avalanche Slope" warning sign" to gain the road and then proceed to Reflection lakes -- a route that might be more appropriate in the "Challenging" category.

Thanks for your efforts in making these rating -- I hope they will help avoid needless tragedy.

Thanks -- at some point it would be useful to provide more detail about the routes being rated.
Thanks for your efforts in making these rating -- I hope they will help avoid needless tragedy.

More detail. Anyone is welcome to submit additional information for each rating. However, I think this type of information belongs here, rather than on my blog. The main trip reports page has several sections of ski route photos for important regions in WA. Maybe the ratings, along with additional trip data, could be posted in that section?

I don't have time to delve into the methodology used to assign the ratings, and this subject is of little interest to most people. In addition to examination of contour maps, aerial photos, and guidebook data, these ratings were in validated in part by extensive computer analysis of digital terrain models.

Thanks for the kind words. I'm not sure if the ratings serve any practical purpose for many of the skiers on this board, but it is interesting work.