Northern San Juan

Snowpack

Susan Hale · Jan 15, 2012 · Northern San Juan

Weather

Mostly sunny with scattered clouds building from the south. Chilly. Breezy. Windy near treeline or open areas (15-20mph). Winds kept most snow surfaces cold today (incoming snow will not bond well).

Snowpack

Note: Stayed near and below treeline. Only a couple of surprises today....otherwise, mostly what one would expect - facets, facets, facets, with some weak crusts on top. Surprise #1 - Crust on the W aspect was weaker than expected with large, loose facets underneath to the ground. Long, hollow chains of facets/depth hoar were hanging below these very friable MF crusts (made of well formed but sintered facets..). Thought we'd see a (little bit) stronger crust here. Surprise #2 - An E aspect with a very thin weak crust over large and loose facets to the ground. Thought the crust might be stronger here too... Found other E aspects with varying crust strengths (but generally breakable under skis). Slightest aspect change or steepness made a big difference on these easterlies... Near treeline N aspect had significant wind damage with highly variable wind-slab formation - a pocket of soft, then a pocket of supportive slab to a pocket of breakable. Not skiable - at least not by me. Northerly below TL was (surprise, surprise) generally large loose facets (except for old tired ski tracks - that were almost chewed up by the faceting process). Were able to push out a few small facet sluffs on steeper terrain. Last week's newer snow is faceted. What we could see above treeline on N - NE aspects was also wind damaged and would expect these zones to have varying depths of hard slab. S aspects below TL had strong supportive crusts. NOTE - All surfaces on most aspects were dusted with facet forms! An inch of water on a given slope would trend hazard up (example - 8" plus wind...). Watch for propagation to steeper or more heavily loaded slopes. Reminder about potential to trigger steeper slopes above you from lower angle slopes below.