Northern San Juan
AvalancheColin Mitchell · Feb 21, 2020 · Northern San Juan
Weather
Very nice spring-like day. Sunny and warm, very light winds at pass level. Some high thin clouds were around in the morning, with a few lower, thicker clouds moving in later in the afternoon.
Snowpack
The snowpack in this area of the corridor is quickly transitioning to spring. West Lime holds ~120 cm of dry, wintry snow, the only hint of the recent heat wave is a very thin sun crust on the surface. Otherwise, the snowpack is well consolidated 1F-P-hard rounding facets with 10 cm of F-hard NSF at the surface. Steep south and southeasterly slopes have already transitioned into a largely homogenous, isothermal snowpack. Henry Brown had ~100 cm of moist, rounding facets that were changing to melt-forms, with about 6 cm of wet melt-forms at the surface. Water had percolated to the ground here, and the snowpack was full of ice masses and percolation columns. The Engineers had a similar snowpack to Henry Brown where the slopes were steep and open, but a more wintry snowpack remained in the forest below. The start zones were melting fast, and had less than 24" of snow with some dirt and rocks poking through. East Lime was similar with HS varying from 4" down by the road to about 24" up high on the slope. Very little settlement this week, all of the master stakes had basically the same readings as on the 15th.
Avalanche
No new activity other than a few larger chunks of wet snow falling off of the cliffs from Jenny Parker south to Coal Bank pass.