Quick report
- Red Flags
- Rapid Warming, Poor Snowpack Structure
- Red Flags Comment
- <p>See below.</p>
Thanks much for the hospitality of Park City ski patrol and Mark Saurer and Robby Young in particular.
Snowpack
- Instability Comment
- <p>Looking at structure ahead of the warm-up. The saying is that if you have depth hoar or facets that continue to trouble you during the winter, watch out during the big warm-up. </p> <p>Still with this structure, Robby Young got a PST30/100 on the drought facets 40 cm down. Upper layers were not dry. </p> <p>Robby Young comments: Curiosity on all solars over the next couple days, but really most interested in east and west aspects where weaker/larger FC exists. I’d be more concerned if they were wet, rather than just moist today, but tomorrow is a new day.</p> <p>Forecasting wet snow is difficult, especially when looking for wet slabs and glide avalanches. </p> <p>In the photo below, I poured Kook-Aid down into the snowpack on an east facing slope at 9650' along the PC ridgeline. The Kool-Aid represents free water moving and pooling at suspect interfaces. You'll see the pink water pooling along crust and facet/crust interfaces as denoted by the photo/blue lines. </p> <p>In their 2004 ISSW paper, Chris Lundy and Blase Reardon talked about needing the following for wet slabs:</p> <p>Water factory to introduce water into the layers - we have this from last weekend's small storm.</p> <p>Slab - this is all the snow after the drought.</p> <p>Funny Business - this is the Jan/Feb PWL facets, along with crust interfaces. </p> <p> </p> <p>Interestingly enough, Reardon/Lundy said that in their work in Montana, even though water pooled above crusts, in the 03/05 wet cycles in Glacier NP, it was <em><strong>below</strong></em> the crusts at the facet/crust interface where the wet slabs fractured. </p>