Avoid avalanche terrain, and areas seeing rainfall at higher elevations. Forecasted snow/rainfall amounts vary greatly across the region, so continually evaluate snowpack conditions throughout the day.
Strong southwest wind has formed wind slabs in lee terrain features at higher elevations.
These wind slabs may remain the main avalanche problem in the east side of the region, where less new snow and rain are expected, and freezing levels may stay below treeline.
These slabs may be touchiest if they are sitting on a weak layer of surface hoar or faceted snow.
On the western edge of the region, moderate to heavy snowfall is likely to build reactive storm slabs as temperatures rise.
Rain will fall up to treeline in most of the region, and into the alpine west of Smithers. In many places, this rain is hitting dry snow for the first time. Expect widespread wet loose avalanches in steep terrain that is seeing moderate to heavy rainfall.
Freezing levels are generally rising to treeline for Wednesday, but weather models are not agreeing on how much precipitation will make it inland. We could see a range of 15 to 40 cm of snow in the alpine and rain below, but areas right around Smithers and east from there may see almost none.
TUESDAY NIGHT: Cloudy. 0-5 cm of snow expected. Strong southwest wind. Alpine temperature around -2 C, freezing level around 1100 m.
WEDNESDAY: Cloudy with snow and rain. 0-40 cm of snow expected above 1500 m and rain below. Strong southwest wind. Freezing level around 1500 m, possibly as high as 2500 m in the southwest of the region.
THURSDAY: Mostly sunny. 0-15 cm of snow in the alpine overnight, rain treeline and below. Strong to extreme southwest wind. Alpine low -5 C. Freezing level dropping to 900 m.
FRIDAY: Partly cloudy. Possible trace of snow expected. Moderate to strong southwest wind. Freezing level rising to between 1000 m and 1500 m.
On Wednesday, we expect moderate precipitation, rising freezing levels, and strong wind to cause a widespread natural avalanche cycle. In areas that see less than 15 cm of snow or 15 mm of rain in 24 hours, natural avalanches will be less likely, but rider triggered avalanches will still be likely.
On Tuesday in the Seaton riding area, our Northwest field team saw a similar avalanche to what they saw on Monday in Sinclair. They also had concerning results in their snowpack tests, and chose a safe path down accordingly. See more details here.
On Monday in the Sinclair riding area, our Northwest field team saw several, size 2, natural wind slab avalanches. These avalanches occurred in alpine terrain on east and northeast aspects. See their MIN report here for more details.
Many large (size 2) wind and storm slab avalanches were observed on the weekend, being triggered naturally and by riders (for example, here).
Expect snowpack conditions to be quite variable across the region. Freezing levels are generally rising to treeline or higher, and the west edge of the region is likely to see moderate to heavy snow/rainfall and strong winds. This will form touchy storm slabs, and the potential for unstable, wet surface snow at treeline and below. Areas near Smithers and east from there will still see freezing levels around treeline, but may only have light snow/rain fall. Strong southwest winds in the drier parts of the region may reduce the effect of the warm temperatures and promote wind slab development.
New snow and rain will fall on mostly unconsolidated snow, and some wind slab in lee terrain features at higher elevations. Storm totals have reached 50 to 70 cm for much of the region since early February. Expect the upper snowpack to be the most unstable where February's snowfall sits on weak faceted snow or surface hoar crystals.
Two weak layers may exist around 70 to 120 cm deep in the snowpack. The first is a surface hoar layer from mid-January and the second is a layer of faceted snow from early January. These layers haven't produced recent avalanches, but the potential remains until these layers bond to the snowpack.
