Avalanche Forecast

Fair - Timing or intensity of solar radiation is uncertain

There is no precipitation in the forecast. The freezing level should drop down to the valley bottoms overnight and then rise up to about 1500 metres during the day on Monday. This pattern is expected to continue for Tuesday and Wednesday. The only uncertainty is how much sun we will see over the next few days. There is a chance of valley cloud and high cloud each day.

On Saturday there was one loose wet avalanche size 2.0 that released from a steep northeast aspect at treeline. I suspect that cooler alpine temperatures and the re-freezing has reduced the likelihood of triggering deeply buried weak layers. Some loose wet avalanche activity may continue if we see strong solar radiation.

Alpine temperatures dropped down to about -7 overnight and the freezing level dropped down close to valley bottoms. This cooling down of the snowpack is expected to develop new melt-freeze crusts on the surface and reduce fracture propagations at buried weak layers. During the warm-up we found approximately 65-100 cm of recent storm snow that is bonding well to a crust buried at the beginning of February; however, this bond is much weaker where surface hoar overlies the crust. Below that, recent snowpack tests gave moderate to hard but sudden collapse results on the mid-January surface hoar where it was found down 70-80 cm on a northeast facing treeline slope. This persistent weakness has been found as deep as 110 cm, or deeper on wind-loaded slopes. The mid-December crust/facet/surface hoar weakness may be persisting in the mid to lower snowpack at higher elevations.