Avalanche forecast

Sea To Sky

Mar 30 – 31, 2022Avalanche Canada
View on map
Archived · expired 5 years ago

Avalanche danger

Fri
Sat
Alpine
2 · Moderate
Treeline
1 · Low
Below
1 · Low
Open full map

Highlights

As we transition to spring, you may find different conditions at every aspect, elevation, and time. Watch for snowpack conditions that change through the day, and as you move through terrain. 

Avalanche problems

  • Wind Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible
    Size
    1–2

    Moderate southwest wind and the possibility of new snow may form small, reactive windslabs over firm surfaces. 

    • Watch for signs of instability like shooting cracks and recent avalanches.
    • Windslabs can be most reactive when they are fresh, so tune in to loading patterns when you see blowing snow. 
    • Use small test slopes to see how windslabs are bonding to the old surface.

  • Loose Wet

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Unlikely - Possible
    Size
    1–2

    Freezing levels are below treeline, but mild daytime warming and spots of intense spring sun could make loose wet avalanches possible. 

    The size of these avalanches will be mostly influenced by how deep the loose snow is. 

    • If there is a solid, supportive crust on the surface, avalanches will be unlikely. 
    • If the temperature is above zero, the sun is on a slope, and there is very little wind to keep the surface cool, avalanches will become likely.

Confidence

High - Confidence is due to a stable weather pattern with little change expected.

Weather Forecast

WEDNESDAY NIGHT: Partly cloudy. Light snow/rain expected. Light southwest ridgetop wind. Freezing level falling to around 700 m. 

THURSDAY: Partly cloudy, possible sunny morning in Whistler. Very light snow/rain expected. Light west ridgetop wind, trending to northwest at higher elevations. Freezing level rising to 1400 m through the day.

FRIDAY: Mostly cloudy. 1-4 cm of snow expected at high elevations. Light southwest ridgetop wind trending to strong at high elevations. Freezing level falling to around 750 m overnight, back up to 1400 m through the day.

SATURDAY: Mostly cloudy with a sunny break mid-day. 3-10 cm of snow expected overnight, with the highest amounts being around Squamish. Light snow/rain through the day. Light southwest ridgetop wind trending to moderate west at high elevations. Freezing level falling to 800 m overnight, back up to 1400 m through the day.

Avalanche Summary

No new and notable avalanches were reported on Wednesday before 4 pm. 

On Tuesday, small, natural loose wet avalanches were reported in steep rocky terrain, along with thin, natural windslab avalanches up to size 1.5 on isolated features in the alpine. Explosive avalanche control produced a few small to large cornice avalanches. 

Snowpack Summary

Around 5 cm of recent snow that fell with moderate southwest wind may have formed small, reactive windslabs on old, firm surfaces. With freezing levels much lower than earlier in the week, a frozen crust is expected on all aspects into the alpine. On the highest peaks, above 2200 m, cold, winter snow may be found in shaded alpine terrain, with a sun crust on south facing slopes.

The rest of the upper snowpack consists of a number of crust/facet/surface hoar interfaces buried in March that seem to have bonded during the recent warm weather. 

The mid and lower snowpack are generally strong and well bonded. 

Terrain and Travel

  • Be alert to conditions that change with aspect and elevation.
  • When a thick, melt-freeze surface crust is present, avalanche activity is unlikely.
  • Watch for wind-loaded pockets especially around ridgecrest and in extreme terrain.
  • A moist or wet snow surface, pinwheeling and natural avalanches are all indicators of a weakening snowpack.

Regions covered