Observation: NWAC Forecaster

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Weather Summary

A strong but shallow temperature inversion had fog and low clouds pushing up into the pass from a very light E wind at lower elevations. This kept surfaces below 3700' frozen. Above the inversion, significantly warmer temperatures and mostly clear skies were found. High broken clouds began to move into the region during the morning and reduced the impact of the sun on the snow.

Avalanche Observation Comments:

No avalanches observed.

Snowpack Observations

Below the inversion layer, the snow surface was very firm and icy and did not soften at all. This melt-freeze crust is very strong and thick. Small pockets of near-surface facets were seen but appeared to be very limited.

The top of the inversion was around 3700' today. Large 10mm+ surface hoar was seen near this elevation in a sort of "bathtub ring" around the valley. It was spotty across the landscape but found in open areas on a variety of aspects.

>~4000'
SE-SW: a very firm and thick (30cm +) melt-freeze crust was the dominant surface. In some areas, it was very smooth and planar. In others, it was very rough and broken. This barely softened before the high clouds moved into the area.
NW-NE: pockets of near-surface facets (1mm) and a facet-crust sandwich were observed. The facet-crust sandwich consist of a very thin (<1cm) and breakable melt -freeze crust over 8-10cm of small near-surface facets resting on a much firmer and thicker crust.