I've been in Rogers Pass the past 4 days. No snow for 11 days and good
stability meant there were
tracks everywhere, both up and down. However, today it snowed (5 cm at the Pass
and 7 cm at
Fidelity) and things are changing, so here are a few observations on what to
expect in the next
little while.
The big issue are the surfaces that got buried today. There is a lot of
variability in this regard and as
such forecasting instability will be complex for the next while. North and west
aspects had
windcrust, steep solar aspects (SE through S through SW) had suncrust,
protected east facing
slopes at all elevations and shaded below treeline terrain had decomposing and
faceted grains on
the surface. On top of these surfaces, on virtually every slope, there was
surface hoar. The size of
these crystals varied, at 2000m and below in sheltered areas it was huge, 20 mm
or more. It was
sluffing downhill in rivulets like water. On other slopes it was smaller, but
still will be very much a
concern. With any sort of load this February 4 surface hoar layer will be very
reactive and
avalanches will occur on it.
Heads up once we get more than a few cms over the next few days!
Mark Klassen
Mountain Guide
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