Avalanche Forecast

Issued: Apr 20th, 2023 4:00PM

The alpine rating is moderate, the treeline rating is moderate, and the below treeline rating is low. Known problems include Storm Slabs and Deep Persistent Slabs.

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It's a challenge to manage different avalanche concerns that vary by elevation and aspect. Observe local conditions and use that information to help select terrain and travel techniques. Match terrain to conditions!

Summary

Confidence

Moderate

Avalanche Summary

Only report is of solar triggered avalanches up to size 2.5 in the afternoon. Please remember there are few eyes still out there regularly reporting field observations.

Snowpack Summary

Anywhere from a trace to 50 cm of recent snow is settling and bonding at higher elevations and north-facing slopes towards treeline. Windslabs are possible in immediate lee features.

On solar aspects at all elevations, and north aspects treeline and below, the recent snow either overlies a widespread melt-freeze crust or there is a crust at the surface. Watch for surface snow becoming moist in the afternoon.

The middle of the snowpack is generally well-settled and strong. A weak layer of facets at the base of the snowpack remains a concern, primarily in alpine terrain with shallow or variable (thick and thin) snowpack depths but also where there's overhead hazard (for example from cornices).

Weather Summary

Thursday Overnight

Mostly cloudy with flurries and anywhere from a trace to 5 cm of snow. Light to moderate southerly ridgetop winds in the Cariboos. Moderate to strong easterly upslope winds in the North Rockies. Treeline temperatures around -5 to -10 C. Freezing level at valley bottom.

Friday

A mix of sun and cloud with only a trace of precipitation. Light, gusting moderate, east (North Rockies) or southerly (Cariboos) ridgetop winds. Treeline temperatures around -5 C. Freezing level around 1900 m.

Saturday

Mostly cloudy with scattered flurries. Just a trace of new snow with 5 cm in favoured snow holes in the North Rockies. Light southwest ridgetop winds. Treeline temperatures around -5 C. Freezing level around 1900 m.

Sunday

Cloudy with flurries, accumulations around 5 cm. Moderate southerly winds. Treeline temperatures around -3 and freezing level around 2100 m.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • If you are increasing your exposure to avalanche terrain, do it gradually as you gather information.
  • Be alert to conditions that change with elevation and sun exposure.
  • Investigate the bond of the recent snow before committing to your line.
  • Be carefull around freshly wind loaded features.
  • In areas where deep persistent slabs may exist, avoid shallow or variable depth snowpacks and unsupported terrain features.

Problems

Storm Slabs

An icon showing Storm Slabs

With recent wind, and various amounts of new snow, anticipate fresh wind slab development. Watch for these wind slab pockets, primarily at higher elevations where cold, dry snow persists. Dial back your terrain choices if you encounter more than 20 to 30 cm of new snow.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 2

Deep Persistent Slabs

An icon showing Deep Persistent Slabs

A weak layer of facets exists near the base of the snowpack. Thinner snowpack areas and areas with variable thick and thin coverage at alpine elevations is where this problem is most likely found. April's warming temperatures may gradually increase the sensitivity of this layer, especially in thin snowpack areas.

Aspects: All aspects.

Elevations: Alpine.

Likelihood

Unlikely

Expected Size

2.5 - 4

Valid until: Apr 21st, 2023 4:00PM