We are barely out of the natural cycle. That puts us in the human triggering phase of the cycle. Be aware of your surroundings and keep tabs on the snow as you travel through the terrain. We are expecting a sudden temperature spike tomorrow.
Weather Forecast
Another warm day is coming down the pipe. We are expecting a rapid warming trend late tomorrow morning. Freezing levels will rise from 1400m to 2200m over a few hours! There may also be some sun poking through the clouds at the same time. Watch for the quick temperature rise! Aside from the temps, there will be some flurries, but no significant accumulation. The ridge top winds will range from 15-30 km/hr.
Avalanche Summary
No new avalanches were confirmed today, however there were too many fresh crowns to rule out the end of the natural cycle. Public photo submissions yesterday informed us of significant avalanches at Burstall Pass. A sz2,5 was remotely triggered near a windloaded alpine feature. In Hero's Bowl, some paths went to valley bottom.
Snowpack Summary
The recent storm snow has settled at all elevations. Below treeline the new snow is a heavy, dense, 30cm thick layer that is sitting on a relatively weak mid pack. There was widespread whumphing in many open, untouched areas today. Shaded areas were slightly drier, but still dense. The moist snow didn't disappear until 2050m. 2050m to treeline still had a distinct slab, but the stronger midpack seemed to handle the load a little bit better. Having said that, whumphing was still observed with very isolated cracking. The Jan31st was down 40 on a west aspect and up to 70cm's on an East(lee)Upper alpine and alpine terrain had obvious wind loading. The certainty of the windslabs prevented us from directly assessing their reactivity, but it is fair to say human triggering is almost certain right now. The load of this recent storm is significant, the snowpack will takes its time adjusting.
Problems
Storm Slabs
Storm Slab avalanches are the release of a cohesive layer (a slab) of new snow that breaks within new snow or on the old snow surface. Storm-slabs typically last between a few hours and few days (following snowfall). Storm-slabs that form over a persistent weak layer (surface hoar, depth hoar, or near-surface facets) may be termed Persistent Slabs or may develop into Persistent Slabs.
Wind Slabs
Wind Slab avalanches are the release of a cohesive layer of snow (a slab) formed by the wind. Wind typically transports snow from the upwind sides of terrain features and deposits snow on the downwind side. Wind slabs are often smooth and rounded and sometimes sound hollow, and can range from soft to hard. Wind slabs that form over a persistent weak layer (surface hoar, depth hoar, or near-surface facets) may be termed Persistent Slabs or may develop into Persistent Slabs.
Deep Persistent Slabs
Deep Persistent Slab avalanches are the release of a thick cohesive layer of hard snow (a slab), when the bond breaks between the slab and an underlying persistent weak layer deep in the snowpack. The most common persistent weak layers involved in deep, persistent slabs are depth hoar or facets surrounding a deeply buried crust. Deep Persistent Slabs are typically hard to trigger, are very destructive and dangerous due to the large mass of snow involved, and can persist for months once developed. They are often triggered from areas where the snow is shallow and weak, and are particularly difficult to forecast for and manage.