The storm is moving across the interior regions tonight resulting in HIGH avalanche danger by morning. Heavy snowfall and strong winds are expected to develop new storm slabs.
Summary
Confidence
Fair - Timing, track, or intensity of incoming weather system is uncertain
Weather Forecast
A moist Pacific storm is moving across the interior mountain regions from the Southwest on Sunday, and is expected to collide with cold arctic air that is anchored on the East side of the Rockies. Areas where the warm moist air meets the cold air should result in moderate to heavy snowfall. The cold air has setup in a Northwest to Southeast tilt which should result in greater amounts of snow in the South and West of the region, and continued cold air with flurries or light snow in the North and East of the region. Overnight snowfall amounts should vary from 5-15 cm combined with strong Southwest winds. On Monday expect moderate Westerly winds and 3-5 cm of snow. Overnight and into Tuesday morning expect 5-15 cm, and another 3-5 before the storm ends on Wednesday.
Avalanche Summary
No new avalanches reported. Expect the developing new storm slab to result in easy triggering or natural avalanches.
Snowpack Summary
New snow and moderate Southwest winds developed isolated pockets of touchy windslab in the alpine and at treeline. Since previous winds were from the north or northwest, wind slabs should be suspected on a wide variety of aspects in exposed terrain. A thin layer of surface hoar with variable distribution was buried on December 27th by about 5-10 cm of light dry snow. As more snow accumulates, this interface could become one to watch. Deeper, at about 40-60 cm below the surface, a persistent crust/surface hoar layer from mid-December can be found. This persistent slab problem is reasonably widespread across the region and is not expected to improve quickly. A deeper crust/facet layer which formed early in the season may still be triggerable from thin or rocky snowpack areas.
triley,
Avalanche Canada
