ACMG Mountain Conditions Summary for the Rockies and Columbia Mountains issued May 20th, 2010

It has been a warm and wet week in the mountains. Not much overnight freezing up until the evening of the 19th.
Rainfall amounts were quite variable across the ranges but it rained hard most places at some point.
Scattered reports showed a cooling last night. In the Rockies at present(5pm) it is raining off and on up to treeline close to the divide and estimates are of 5-10 cm. recent snow above that. At some point this afternoon it was snowing lightly at Rogers Pass but not sticking to the ground.

The excellent snow and ice climbing conditions of late last week are a warm, wet mess right now. This could heal quickly with a good overnight freeze. It would be worth having a poke at the snowpack with an avalanche probe to see how solid the freeze is. I am guessing the snowpack is presently weak and wet to the ground in most places. If I am out this weekend on steep snow I sure want to know if I am walking on a thin crust over the mush or a full depth layer of "concrete". Glacier travel conditions are also totally temperature dependent. coverage is still pretty good but those thinner low elevation snow-bridges will be especially nasty when it is warm.

Glacier Park Avalanche Control Section staff talked about a few big wet slab avalanche and big cornice falls during the warm rains. Lots of the big alpine rock routes in the Rogers Pass corridor are best climbed before the snow disappears at low elevations. However, it seems wise to wait till things have cooled or at least until this warm wet avalanche cycle is over. The alders will be buried for awhile yet.

It seems Banff and Jasper were cooler and they have seen very little recent avalanche activity. There was certainly a big cycle of wet avalanches and melting snow along the east slope of the rockies between the sun and rain effect in the past 3 days.

East slope rock climbing conditions have improved in the wet and heat. Chinamen's pk East and North faces looks mostly dry. The snow is mostly gone above East End of Mt. Rundle except for a few big drifts. I would hold off on climbing on that face till all the snow is gone and all that choss above the cliff gets to dry out and stop moving around a bit. Closer to the Rockies divide you are probably going to run into snow heading up most valleys towards objectives like Louis, Edith, Castle.

Weekend looks like it may be warm and sunny. You know the deal-start early for the snow, keep your head out from under the melting, dripping rock faces and watch out for the fresh crop of holds that were fractured in the winters MANY melt-freeze cycles. The rivers are coming up and yeah, they are still cold.

Larry Stanier
ACMG/IFMGA Mountain Guide

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