ACMG conditions report summary
ACMG Mountain Conditions Report Summary for the Rockies and Columbia Mountains issued May 06, 2010
There has been spotty reporting in the past week, typical for this time of year. What we do know is that winter is alive and well in all the ranges with fresh snow reported everywhere. In a drive from the Okanagan to Banff on May 5, I observed new snow levels well below treeline in the Monashees, Selkirks and Rockies. The main activity people have been reporting on has been skiing.
There is 30-50 cm of storm snow above treeline in the Rockies and one can expect similar amounts in the Columbia Mountains. This new snow is lying atop a thick, hard melt-freeze crust all the way to mountaintop. The good news is that the powder skiing is good and until we get a big heat wave we don't need to be concerned about persistent weak layers. The primary concern at the moment is how the recent snowfalls are bonding to that hard crust. Lee and cross loaded slopes where wind has caused slabs to form will be one type of terrain that should be avoided.
Many of the rock climbing areas in the Rockies, such as Yamnuska, are snow covered. Head for valley-bottom venues in the short term. Spilli near Golden or the Revelstoke crags may be an option. I just came from the Skaha cliffs near Penticton and although most of the time we dodged rain showers and belayed in down jackets it was climbable every day.
Only the highest elevation north facing ice climbs are still in but expect it to be winter up there. The same goes for mountaineering activities.
Forecasts are looking optimistic for more seasonal weather to begin in the coming week. If it heats up rapidly expect a major spring avalanche cycle to occur with the recent snowfalls sliding on the hard crust beneath. If an extended heat wave or rain occurs the old weak layers deep in the snowpack could wake up and produce very large slab avalanches. On rock climbs expect rockfall to be a factor with warming temperatures and avoid areas where there is snow or wet rock above you.
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