This stuff has been causing all sorts of problems lately, not least a few avalanches with fatal consequences. Locally, a walker died from injuries sustained when he was swept downhill by avalanche on the side of Liathach, which shows how dangerous it can be for walkers as well as climbers on the hills.
Apparently, the severe hoare frosts which form as large ice crystals cause subsequent snowfall to slide off the top. This can occur anywhere there's a slope.
Take care out there & please remember the Mountain Rescue teams when you feel the need to dip into your pocket, it could be any of us in need of them.