South Coast Inland Avalanche Forecast

Issued: Mar 20th, 2021 4:00PM

Sun Mar 21st Current Conditions
Alpine Moderate Treeline Moderate Below Treeline Low
Mon Mar 22nd 2 Day Outlook
Alpine Considerable Treeline Moderate Below Treeline Low
Tue Mar 23rd 3 Day Outlook
Alpine Moderate Treeline Moderate Below Treeline Low

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

Heightened avalanche conditions exist on steep slopes that have been loaded by the wind.

Summary

Confidence

Moderate - Uncertainty is due to the timing of the incoming weather system.

Weather Forecast

A cold front crossing the region on Sunday night will bring 10-20 cm of new snow.

SATURDAY NIGHT: Cloudy with some isolated flurries, 20-40 km/h southwest wind, treeline temperatures drop to -8 C.

SUNDAY: Cloudy with flurries picking up in the afternoon with 5-10 cm of snow by the evening, 40-60 km/h southwest wind, treeline temperatures around -5 C.

MONDAY: Another 5-10 cm of snow by the morning then sunny in the afternoon, 20-30 km/h southwest wind, treeline temperatures around -5 C.

TUESDAY: Mostly cloudy, 20-30 km/h southwest wind, treeline temperatures around -5 C.

Avalanche Summary

On Friday there were reports of a few small cornice releases around the Duffey area and some glide slab releases in the Cascades. With continued wind and snowfall on Sunday, wind slabs could be reactive to human triggering on steep terrain features.

Snowpack Summary

Another 5-10 cm of new snow by Sunday afternoon will add to the 15-30 cm of recent snow from the past few days. This snow has been accompanied with moderate to strong wind from the south and west, so reactive wind slabs could be found in lee terrain features. This new snow overlies a melt-freeze crust up to around 1700 m and higher on sun-exposed slopes or dry snow on northerly aspects at high elevations.

Remember that cornices along ridgelines are large at this time of year and always have the possibility of failing naturally or from the weight of a human.

Terrain and Travel

  • Watch for newly formed and reactive wind slabs as you transition into wind affected terrain.
  • Back off if you encounter whumpfing, hollow sounds, or shooting cracks.
  • 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

Possible-Likely

Expected Size

1 - 2

Continual flurries and moderate to strong southwest wind will likely form wind slabs at upper elevations. Assess for the formation of slabs if you venture to steep, leeward terrain.

Aspects:

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

Elevations:

Alpine, Treeline.

Valid until: Mar 21st, 2021 4:00PM

Forecast Trend

The latest forecast danger ratings, broken down to elevation. See how an elevation is trending.