Mountain Conditions Summary for the Rockies and Interior Ranges. July 29th,
2005
Summer is definetly here in the valleys and up to treeline. However, above 3000
meters it still feels more like June than late July. This situation in the
Alpine has been a bit of a blessing and a curse.
First, the blessings.
Snow cover is still extensive on the glaciers. Travel on glaciers has been
generally excellent. All normal glacier travel precautions should be taken but
almost all reports from guides in the field refer to good travel conditions and
crevasses are generally well bridged for midsummer. Bare ice is starting to
appear on the icefields and all low elevation glacial tongues are mostly bare
ice. Alpinists are well advised to take crampons for all glacier travel. I
personally haven't had to use crampons once this season but the odds of being
that lucky diminish every sunny day. A good example of the excellent snow cover
for late July is the Bugaboo/ Snowpatch col in the Purcells. All reports from
the Bugaboos to date still speak of good snow cover, no bare ice and that the
midslope bergschrund is just starting to require some careful navigation to get
around. I am sure this situation is staring to deteriorate quickly but by this
date in the past two summers it was very icy, required some tricky crevasse
crossing and was subject to lots of potentail rockfall.
Alpine rock routes in the Selkirks, Purcells and Rockies are generally in
excellent conditions on all aspects, with the caveat that low angle ridges
above 3000 meters may still put up a good fight with deep snow and cornices.
Now, the curse.
The big classic snow and ice faces and ridges also still have extensive snow
cover. The June monsoons have left the moderately steep terrain above 3000m
with a spring snowpack that is still trying to adjust to summer. The long spell
of poor weather never gave the snowpack a chance to settle and gain strength as
it "often" does in June and July. Alpinists can get in some fantastic snow and
ice climbing right now but you must be very aware of where the snow is in the
melt/freeze cycle. Clear nights are almost mandatory for safe travel on the
big,steep,snow slopes. Do not rely on simply kicking the snow surface to test
it strength. Consider digging down, probing or at least poking with your ice
axe to estimate the depth of the overnight freeze. Think ahead about how the
daytime heating and the sun will cause the slopes on your route to lose
strength during the day. Remember that generally, the higher you go, the more
like Spring rather than summer it will feel. My personal observation has been
that the snowpack consists of unusually large snow grains for this time of year
and therefore it has the potential to lose strength faster than we are used to
in summer.
After five days of good weather and more in the forecast conditions are
obviously in a period of change. Avalanche hazard forecasting will generally
become more predictable (generally stable conditions with a good freeze,
deteriorating stability with daytime heating and solar radiation) if the
forecast is correct and more rock and ice will start to appear. The downside of
this is that our old summer nemisis, rockfall, shall start to increase. The
retreat of permanent ice has meant LOTS of rockfall in terrain that hasn't seen
the sun in hundreds of years and is now melting out. Think hard about where you
are going and when and where you might expect spontaneous rockfall.
Larry Stanier
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