Kootenay Boundary

Watch for fresh wind slabs which may exist in atypical terrain features. Westerly wind may have southerly or northerly components, depending on elevation. Isolated surface hoar may exist beneath recent snow at lower elevations, approach steep tree line convexities with caution.

Saturday night: Increasing cloud, alpine temperature around -10. Wind light southwest at lower elevations, increasing to strong west to northwest above 2000 m.

Sunday: A mix of sun and cloud, possible flurries. Freezing level rising to 1500m. Wind light to moderate southwest at lower elevations, moderate to strong west to northwest at ridgetop.

Monday: Flurries bringing a trace of snow. Freezing level 1600 m. Moderate to strong southwest wind.

Tuesday: A mix of sun and cloud with isolated flurries. Freezing level 1500 m. Moderate southwest wind.

Recent reports have indicated quite limited natural storm slab activity size 1-2. On Thursday and Friday, storm slabs were touchy to skier and explosive control work size 1-2.5 on a variety of aspects above 1800 m. By Saturday, wind slabs were stubborn to human triggers, and we had report of a single size 2 explosive control result.

At upper elevations, 20-40 cm of recent snow has seen some wind affect and is likely undergoing continued transport as winds pick up into Sunday morning. Wind direction has been predominantly westerly but may also have southerly or northerly components, depending on elevation. Rising freezing levels on Sunday may promote settlement and slab development in the previously cold, dry snow at lower elevations. This could result in isolated reactivity where this snow sits over surface hoar.

A couple of persistent layers exist 60-80 cm and 80-150 cm below the surface, having formed in mid-February and late January, respectively. These are composed of combinations of surface hoar, crusts and facets. Steep, open slopes at treeline elevations have been the most likely spots to trigger large avalanches on these layers. While avalanche activity on these layers has dwindled significantly in the past week, they continue to show results in snowpack tests. So while overlying snow is likely promoting bonding at these interfaces, they're still on our radar for now.

Shallow snowpack areas in the east of the region may harbor a facetted basal snowpack as described in this MIN report. This structure is often a constant for thin snowpacks and can be managed with good travel habits of avoiding shallow rocky areas where the snowpack transitions from thick to thin.

• Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
• Approach steep open slopes at and below treeline cautiously, buried surface hoar may exist.
• Watch for signs of instability like whumpfing, hollow sounds, shooting cracks or recent avalanches.