Observation: NWAC Forecaster

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Weather Summary

Thick valley fog made lower elevations feel soggy, although there was no precipitation. Once above the cloud deck at around 4000-4500ft, partly cloudy skies and sunshine were a nice treat. Winds were calm in the morning, then picked up in the afternoon. Ridgeline winds in the afternoon were moderate but enough to drift snow around.

Snowpack Observations

A thin snowpack exists at lower elevation trailheads, particularly on these southerly aspects. There was a dusting of new snow in the parking lot and minimal new snow depths until around 4000ft.

At approximately 5000ft on a south aspect, I found a shallow HS of 30cm, with 20cm of recent snow over the Christmas Crust. The new snow had a favorable bond with the underlying crust, and I did not locate any weak faceted grains or surface hoar in this location.

I wanted to target areas that were likely to have buried surface hoar and found a sheltered, sparsely treed meadow on a north aspect as a prime location. At this spot (5800ft, N aspect), there was an HS of 110cm. I found the layer of buried surface down 27cm mixed with other types of decomposing particles. Snow stability tests and nearby test slopes produced unremarkable results. ECTN15, PST 33/100 SF (slab fracture) I dug quick pits in a number of other locations and found the distribution of surface hoar to be specific to well sheltered north-facing terrain with sparse trees. The Christmas Crust was buried approximately 50cm deep, snow on top of this crust seemed to be bonded well in most locations.

At ridgelines, there was blowing snow and moderate winds. It was enough to fill back in my snowmobile tracks in a short period of time.