South Coast Inland

A strong winter storm system is expected Monday night into Tuesday. Significant snow is expected, however amounts are uncertain. If local snowfall amounts exceed forecasted values, avalanche hazard will increase.

Moderate - Forecast snowfall amounts are uncertain

Forecasted snowfall amounts for Monday night & Tuesday are uncertain. Higher amounts are expected for areas near the Coquihalla.TONIGHT: Snow. Accumulation 10-20 cm. Ridge wind strong to extreme, southwest. Alpine temperature near -3. Freezing level 1200 m.TUESDAY: Cloudy, snow. Accumulation 5-20 cm. Ridge wind strong to extreme, west. Alpine temperature near -3. Freezing level 1400 m.WEDNESDAY: Mix of sun and cloud. Ridge wind light to moderate, northwest. Alpine temperature near -5. Freezing level 1400 m.THURSDAY: Cloudy, flurries. Accumulation up to 5 cm. Ridge wind light to moderate, west. Alpine temperature near -5. Freezing level 1200 m.

On Sunday there was a report of a skier triggered storm slab (size 1) on a westerly aspect in the high alpine, as well as sloughing in steep terrain.Saturday there was a report of a skier triggered size 1 storm slab on a north aspect at 1800 m, as well as a natural, size 2 on a west aspect at a similar elevation.Last week, on Thursday and Friday there were reports of isolated natural and skier triggered storm slab avalanches (size 1-1.5) from 15 to 30 cm deep on wind-affected convex and ridge top features in the alpine.All reports of recent avalanche activity have been from the northern part of the region. In the south only sloughing in steep terrain and thin wind slab activity in recent storm snow has been observed.

Another 10-15 cm of snow Sunday night adds to last week's storm snow bringing totals to 20-40 cm of recent storm snow that sits on a crust that is present at all elevations on solar aspects as well as low elevation northerly aspects. On northerly and east aspects at treeline and alpine elevations the storm snow sits on a mix of large surface hoar and surface facets.Deeper in the snowpack in the north of the region, polar aspects (those that face north and east) are harboring cold snow and a surface hoar interface buried early March that is about 30-50 cm below the surface. This layer exists at alpine and treeline elevations, but it is not everywhere. This layer has produced large human triggered avalanches in the north of the region in the past week.Also in the north of the region a weak layer buried mid-February is about 60 to 80 cm below the surface and has been reactive in snowpack tests. The layer is composed of sugary facets, a sun crust on solar aspects, and surface hoar that is present at and below treeline. In the south of the region, around the Coquihalla and in Manning Park, the recent storm snow overlies a recent crust that caps a well settled snowpack.