A stable high pressure system with record breaking warm days and cool
clear nights dominated the Rockies and Columbias over the last week.
The fresh snow from early September has mostly melted off and as of
September 16th only high glaciated terrain and upper elevation north
aspects were still holding the snow.
All this changed today. The high pressure ridge started breaking down
last night, and today (Sept. 17) the Rockies saw the arrival of rain
showers and unsettled weather. Peaks along the Continental Divide got
a dusting of new snow above 10,500 feet. No recent reports have come
in from the Selkirks or Purcells, but unless you hear otherwise, I
would expect a fresh dusting of snow on the higher peaks in these
areas as well.
The forecast for the weekend is calling for a westerly flow with
cooler temperatures, mixed sun and cloud, and showers in some areas
west of the Continental Divide.
The alpine rock routes and ridges are mostly dry, but expect some
snow on the rock at higher elevations. The alpine ice routes will have
to be evaluated for rock fall potential, but the cool nights and bit
of new snow sticking to the ice is starting to bring these routes back
into shape. The key thing to keep in mind is that the weather is
somewhat unsettled and, unlike the last week of perfect weather, there
may be some afternoon build up and rain showers.
Weak snow bridges on the glaciers are still a significant hazard. Many
of the crevasses will be covered over (and hard to see) by a thin
layer of new snow, but the bridging strength of this snow will be
minimal. Lots of probing and conservative route choices are in order
on the glaciers at this time of year.
Brian Webster
Mountain Guide
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These observations and opinions are those of the person who submitted them. The
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continuity. Conditions differ greatly over time and space due to the variable
nature of mountain weather and terrain. Application of this information
provides no guarantee of increased safety. Do not use the Mountain Conditions
Report as the sole factor in planning trips or making decisions in the field.
Please check out http://acmg.ca/mcr for more information.
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