Northern San Juan
Avalanchem ackerman · Apr 5, 2020 · Northern San Juan
Weather
29F at Eureka at 0730- Warm morning. Steady SW winds kept it cool ATL but solar impacted slopes and sheltered areas NTL and BTL warmed quickly! West facing aspects that had a marginally frozen temp crust from the last two days had warmed by noon. Some clouds this am gave way to mostly clear this aft. -Bright sun, blue sky, spring temps.
Snowpack
a good look at the alpine northeast of town. BTL temp crusts. NTL & ATL temp and wind crusts. The alpine is a mix of cross loaded, heavily wind impacted topography, bullet proof strugi with softer spots here and there. Cornices small to very large present on N>NE facing ridgelines- evidence of recent cornice fall atop NW facing couli. avg HS 180 @ 12k -Dug on a north northwest facing aspect at 12k- -found a 3 cm surface crust atop 12cms of F hard fresh DFs -faceted layer of concern below this week's fresh snow- ~20cm down -mid pack slab is still present and is stout- approx 80cm thick and composed of many former surface, crust/facet layers> trending from 4 F to 1 F to P -this sits atop 90 cm of 4F facets to the ground Pack was stubborn and didn't give it up on a long column. ECTX- no initation or prop BUT, non-standardized shear tests did get the block to pop 70 cm down (bottom of midpack slab) Clean, fast and hefty. If you could get the persistent slab to go.....it'd be beefy.
Avalanche
Lots of evidence from loose wet cycle earlier in the week- (est. Friday) Loose wet action evident and observed on both East and West>SW aspects NTL East facing gullies and ice flows are melting out quickly and running as wet slides down to CR 2 many debris piles collected at the road/on the road