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Jonathan wrote:
>The “best” one I ever read was a UT fatality under Moderate conditions.  A
>touring partner with some indirect connections to the incident told me it
>undermined his faith in avy bulletins.
>Well, the bulletin that day was indeed Moderate, but highlighted about five
>very specific danger factors to avoid that day.  The USFS incident report
>read almost like the victim had gone out with a checklist for his tour,
>trying to simultaneously expose himself to all the noted factors.

I think the "moderate" descriptor is the most misunderstood of the 5 avi danger ratings. A lot of folks seem to take the attitude "The danger rating is only moderate. It's no big deal" and make arrogant assumptions like "We didn't think there was enough snow to slide. Besides, there were recent tracks."  Even experienced people seem to forget that moderate means:

Natural avalanches unlikely. Human triggered avalanches possible.

Unstable slabs possible on steep terrain.

Use caution in steeper terrain on certain aspects (defined in accompanying statement).


I often wonder how many B/C travelers fully read the morning report on a "moderate" day. For example, here are the pertinent excerpts from today's Wasatch report:


"It’s apparent that we have a slab sitting on a persistent weak layer of facets.  There is a crust associated with this weak layer in some areas as well.  The weakness varies from place to place making hazard evaluation “tricky” as one of our observers puts it.  This is a perfect “booby trap” type snowpack as you will find mostly stable snow in many areas, then, just around the corner you may trigger a slab avalanche.  The weakness is buried deep enough to make the size of these avalanches quite dangerous.

The avalanche danger remains MODERATE on slopes steeper than about 35 degrees, with both loose sluff and slab avalanches possible.  In my opinion, this type of moderate danger makes for some of the most difficult hazard evaluation.  These are conditions that often catch even the most experienced backcountry travelers."

-marc

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