Avalanche Forecast

Issued: Mar 25th, 2023 4:00PM

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

Avalanche Canada jpercival, Avalanche Canada

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Expect the sun and warm temperatures to rapidly unconsolidated the upper snowpack and promote the creation of both wet and dry loose avalanches. Carefully consider your terrain choices prior to committing to steep avalanche terrain, especially as daytime temperatures rise and the sun appears.

Watch for lingering wind slabs that may remain reactive to human triggering.

Summary

Confidence

Moderate

Avalanche Summary

On Friday, a few large (size 2) glide slab avalanche releases occurred and noted cracking and buckling was observed on know areas with basal rock slab features. A few ridgetop cornice failures that tested slopes below with no slab release.

On Wednesday, avalanche activity has begun to subside as only a few small ( size 1) loose wet avalanche were reported and initiated from very steep south aspect terrain at treeline elevations and below. On specific terrain features such as smooth rock slabs, glide slab cracking and buckling was reported,

On Tuesday A few naturally triggered small loose wet avalanches were observed with one large (size 2) that initiated in a steep rocky feature in the alpine running onto the glacier below. A noted natural small (size 1) wind slab avalanche on a northeast aspect in the alpine was reported. Additional reports of large (size 2) glide slab avalanches occurring on a south aspect in terrain with rock slab features being the ground roughness characteristic.

On Monday, numerous small wet loose avalanches (size 1) were observed on steep, rocky solar slopes at higher elevations.

If you head out in the backcountry, let us know what you are seeing by submitting a report to the Mountain Information Network.

Snowpack Summary

Variable winds have built wind slabs on exposed terrain features near ridgetop. Below 1800 m moist snow or a refrozen melt freeze crust covers the surface. The crust extends up to 2000 m on solar aspects. During periods of daytime warming surfaces on all aspects below 1300 m are becoming unconsolidated and moist. Above this elevation only direct solar aspects are affected by the sun.

The middle of the snowpack is strong and contains numerous hard crusts.

The lower snowpack is composed of weak basal facets. This layer has produced limited recent avalanche activity, however it can quickly become active again with any significant change to the snowpack, such as rapid loading (heavy snowfall or rain) or prolonged and extensive warming.

Weather Summary

Saturday Night

Cloudy with periods of clearing, no new precipitation. Light northwest winds at ridgetop. Treeline temperature -6°C. Freezing levels descending to sea level.

Sunday

Cloudy with some periods of clearing no new precipitation. Light to moderate southeast winds at ridgetop. Treeline temperature 0°C. Freezing levels 1100 m.

Monday

Cloudy , becoming clear in the afternoon. No new precipitation. Light to moderate northeast winds at ridgetop. Treeline temperature 0°C. Freezing levels 1100 m.

Tuesday

Cloudy , becoming clear in the afternoon. No new precipitation. Light to moderate northeast winds at ridgetop. Treeline temperature 0°C. Freezing levels 1500 m.

More details can be found in the Mountain Weather Forecast.

Terrain and Travel Advice

  • Be carefull around freshly wind loaded features.
  • Avoid thin areas like rock outcroppings where you're most likely to trigger avalanches failing on deep weak layers.
  • Pay attention to cornices and give them a wide berth when traveling on or below ridges.

Problems

Wind Slabs

An icon showing Wind Slabs

Storm snow has been redistributed by switching winds and creating deeper deposits in exposed alpine and treeline features.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 2

Deep Persistent Slabs

An icon showing Deep Persistent Slabs

Weak, sugary faceted grains exist near the base of the snowpack. Riders are most likely to trigger this layer on steep, rocky slopes where the snowpack is thin and shallow. The likelihood of avalanche activity on this layer will increase during periods of rapid change to the snowpack, such as heavy snowfall, rain, or rapid warming. Cornices are also very large at this time of year and a cornice failure could trigger this layer.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely

Expected Size

2 - 3.5

Loose Wet

An icon showing Loose Wet

When temperatures rise and the sun appears expect on steep south aspect terrain that a natural wet loose avalanche cycle will occur. Even a small loose wet avalanche has enough mass to push a skier into a terrain trap such as a cliff or gulley.

Aspects: South East, South, South West, West.

Elevations: All elevations.

Likelihood

Likely

Expected Size

1 - 2

Valid until: Mar 26th, 2023 4:00PM