Avalanche Canada mconlan, Avalanche Canada

Sea to Sky Avalanche Forecast

Feb 19th, 2020 4:00PM

The alpine rating is low, the treeline rating is low, and the below treeline rating is low. Known problems include Wind Slabs.

Another day of sunny skies to enjoy. Isolated wind slabs may linger in steep alpine terrain. Sunny skies may wet the snow on sun-exposed slopes and weaken cornices.

Summary

Confidence

High - Confidence is due to a stable weather pattern; little change is expected for several days.

Weather Forecast

WEDNESDAY NIGHT: Clear skies, light south wind, alpine temperature -3 C, freezing level 1100 m.

THURSDAY: Clear skies, light to moderate southwest wind, alpine temperature -3 C, freezing level 1400 m.

FRIDAY: Mix of sun and cloud, light to moderate southwest wind, alpine temperature -5 C, freezing level 1000 m.

SATURDAY: Cloudy with light snowfall and afternoon clearing, accumulation 5 cm, light northwest wind, alpine temperature -8 C, freezing level 1000 m.

Avalanche Summary

No new avalanches were observed on Tuesday.

Snowpack Summary

Clear skies have formed a melt-freeze crust on sun-exposed aspects, which will moisten during daytime heating. Soft snow should prevail on shaded aspects, which overlies hard surfaces and potentially surface hoar in sheltered terrain around treeline. Isolated wind slabs may still linger in steep, lee terrain features in the alpine. The clear skies are allowing for surface hoar to grow, which may become problematic after the next large snowfall.

The midpack is well-settled. Faceted snow and crusts exist near the base of the snowpack in much of the region. Avalanche activity was recently noted on Curtain Glacier in the Spearhead Range, although it is unclear if the avalanches released on this basal instability. This layer is largely dormant at the moment but appears to be most likely a problem on the eastern side of the region, in alpine terrain, and where there is relatively smooth ground (e.g., glaciers, scree slopes, rock slabs).

Terrain and Travel

  • Carefully evaluate steep lines for wind slabs.
  • Avoid sun exposed slopes when the solar radiation is strong, especially if snow is moist or wet
  • Pay attention to cornices and give them a wide berth when traveling on or below ridges.

Problems

Wind Slabs

An icon showing Wind Slabs

Likelihood

Unlikely

Expected Size

1 - 1.5

Isolated pockets of wind slab may linger in steep, alpine terrain.

Aspects:

North, North East, East, South East, North West.

Elevations:

Alpine.

Valid until: Feb 20th, 2020 5:00PM