Observation: NWAC Forecaster

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Weather Summary

The morning was mild, but temperatures at the trailhead were below freezing, and surfaces were frozen and supportable. We enjoyed blue skies and pleasantly warm temperatures throughout the early part of the day. However, around 1:30 pm, high clouds began to expand from west to east, and the sky was overcast by the time we were back to the SnoPark.

We saw widespread D1-D2 wet loose avalanche cycle from earlier in the week, and there were a few smaller, more recent wet loose avalanches off of steep rocks and cliffs that occurred today. Many cornices had also sagged, shed, or failed with the recent warm temperatures.

Snowpack Observations

We traveled from 2400ft to 4700ft via snowmobile before switching to human-powered travel methods to climb to 5300ft on east and north aspects. Snow surfaces were frozen in the morning, which made stopping to cool down the snowmobiles necessary. While slopes are melting out quickly on steeper southerly aspects, travel on groomed trails to access high elevations is still easy going. Surfaces softened nicely on sunny slopes, while shady terrain remained icy but edge-able. While you could find a few soft spots, most surfaces remained supportable with just a few inches of boot penetration.

Evidence of the widespread wet loose avalanche cycle from earlier in the week was easy to find. However, today any wet loose avalanche activity was limited to snow shedding off very steep rocky terrain.

We dug into the snow at 5300ft on a north aspect to look for any weak faceted snow that may have been buried on March 8th. We did not find any faceted grains over the Early March Crust in this location. The surface had a 4cm thick melt-freeze crust over 30cm of 1F+ small rounded grains on top of the Early March Crust. While we may not have been high enough in elevation to locate the facets, the most notable observations we made was a lack of slab avalanche activity in near treeline and above treeline terrain up to 7000ft. We even observed a large cornice collapse that landed on a very steep north-facing slope and stuck there without triggering a slab. These high elevation northern slopes had some small rollerball activity, and looked shiny and icy in the bright sun.