[MCR] spring avalanche cycle

Subject: [MCR] spring avalanche cycle
Date: Fri, 13 May 2011 07:19:39 -0700
The Canadian Avalanche Centre posted this week’s avalanche bulletins for all forecast regions yesterday. You can find these bulletins here: http://www.avalanche.ca/cac/bulletins/latest. Many of you sent information and observations that were very helpful in preparing these updates. Thanks. Keep the information coming over the weekend and next week: send to forecaster@xxxxxxxxxxxx or call/email me directly (contact info below). Our final update for the season will be issued on Thursday, May 19.
 
Of note this week are reports of a widespread avalanche cycle in the Rockies but I suspect it’s also happening in other areas of the interior. Numerous size three avalanches are failing deep in the snowpack, on the ground, and running to the snowline. I’d guess that really big ones might even run into the grass and brush below the snowline so climbers, hikers, ATVers, and hunters beware. What details we have are in the bulletins mentioned above. This cycle is likely to continue through the weekend with warm temperatures and sunny conditions forecast for most of the interior. Where this is happening, it’s the first big spring cycle of the season and, while it will likely slow down a bit after a couple of days, conditions will remain challenging and somewhat unpredictable until a decent freeze occurs. Once we’ve had a couple of cold, clear nights I expect to see more normal spring avalanche conditions where the diurnal melt-freeze cycle is the primary driver of avalanche danger.
 
The coasts have been a bit cooler and wetter and we have not heard of widespread, unusual avalanches there but it’s definitely spring out west as well so keep an eye on the effects of gradually warming temperatures and rain. When the sun comes out, expect avalanche activity to pick up and it’s not impossible that some of them will be big, deep ones.
 
In all areas, obtain information about conditions from knowledgeable locals before venturing into avalanche terrain. And this season, you’ll want to ensure that everyone in your party has avalanche rescue equipment even though it’s mid-May—there’s still huge amounts of snow in the mountains.
 
Keep your head up if you are going into the mountains this weekend.
 
Karl Klassen
Public Avalanche Warning Service Manager
Canadian Avalanche Centre
Revelstoke, BC
250-837-2141 ext 227 (office)
250-814-3756
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