Recent warm temperatures have started to melt the surface of the snow. South facing aspects will be the most likely place to see the solar effect on the snowpack. Loose wet avalanches are possible at lower elevations. Once you see pinwheeling or loose snow sliding on the surface, it’s already too late to be on that slope. Pockets of wind slabs still exist at high elevations on steep, open and wind loaded slopes.
Wind slabs can be found on windward slopes below ridge lines. Wind etching and cornices are a good indication that wind slabs may be present on the slope in question.
Cornice build on Jeru Peak in the Selkirks. This is the N face of Jeru. This is a good example of a place to find wind slabs.
Wet loose avalanche are possible. The most likely place to find conditions for wet loose would be on aspects in the sunshine (SW-S-SE)
Pinwheeling 2.10.22
Picture- Silver Valley
The last couple of days have brought the most change to the snowpack that we’ve seen in a while. Up until a couple days ago, Cooler air temperatures combined with cloud cover had kept the snowpack cold and preserved.
This week’s weather brought higher temperatures and more sunshine resulting in changes the snowpack based on different aspects and elevations. Warmer temperatures at lower elevations have started to melt the snow. I’ve noticed water running under the snow, snow depths shrinking and creeks flowing higher which are all signs of a warming snow pack. The snow is re-freezing at night which can contribute to tricky travel conditions in the mornings.
Even at 4800’ near tree line, the snowpack is showing signs of warming. I dug a snowpit on a SSE facing slope on Wednesday afternoon and was surprised to see that the temperature of the snow throughout the whole snowpack was 0 degrees. That tells me that the warmth is penetrating all the way through the snowpack. As the warm weather continues, this effect will be stronger and continually increase the chances of wet avalanche activity.
Above treeline is a mixed bag. NE-N-NW are still holding the cold in the snowpack which means the changes haven't have been limited . South faces at high elevations have seen the sun, warm temperatures, and wind transport.
All of this means that decision making is getting trickier. You need to pay attention to the elevation and aspect you are on because warming will be different based on aspect and elevation. Enjoy the sunshine but be aware of what is happening to the snow under your feet. If you’re looking for good skiing, check out low angle, north facing trees. Have a great day!
