Avalanche Forecast

Issued: Mar 14th, 2019 6:16PM

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

ghelgeson, Avalanche Canada

Sea To Sky.

Seek out cold dry snow on higher elevation north and east aspects but watch for wind slabs which remain sensitive to triggering. The sun could produce loose wet avalanches on unshaded slopes, especially in the afternoon.

Summary

Confidence

Moderate - Timing or intensity of solar radiation is uncertain on Friday

Weather Forecast

Friday offers one last day of temperatures on the cool side before the heat really comes on for the first time this season. THURSDAY NIGHT: Freezing level around 800 m, light to moderate west/southwest wind, 1 to 3 cm of snow possible.FRIDAY: Broken cloud cover, freezing level rising to 1500 m, light southwest wind, no precipitation expected.SATURDAY: Broken cloud cover, freezing level rising to 1800 m, light southwest wind, no significant precipitation expected.SUNDAY: A few clouds, freezing level approaching 3000 m, light variable wind, no precipitation expected.

Avalanche Summary

Wednesday was an active day for avalanche activity. Loose wet releases were common on steep solar aspects to size 2. This MIN from Decker Meadows does a great job of showing just how quickly the very strong spring sun can produce avalanches with some great photos and a positive outcome. We suspect activity like that described in this MIN will probably pick up over the next few days as the region warms considerably. A size 2 natural wind slab avalanche was reported from a north facing feature at 1900 m. A size 1 remote triggered storm slab avalanche was also reported from a north facing feature between 2200 and 2000 m.Small loose wet avalanches were reported on Tuesday on south-facing slopes. There was also a size 1.5 remote-triggered avalanche reported at 1400 m.During the previous storm, there was an avalanche cycle to size 2.5. Operators noted some avalanches showed wide propagations.

Snowpack Summary

Another 15-20 cm new snow added to previous amounts to give storm totals in the range of 30-50 cm. Towards the end of the storm, winds shifted to the north, potentially creating some unusual wind slabs on south-facing slopes. Beneath the recent snow you may find hard wind-affected snow at higher elevations, soft faceted snow in shaded and sheltered areas, and crusts on steep southerly slopes. The middle and lower snowpack is well-settled.

Problems

Wind Slabs

Winds shifted to the north at the end of the last storm, building wind slabs on south-facing slopes. These wind slabs likely remain susceptible to human triggering and the increasingly strong spring sun is capable of producing natural avalanches too.

Be careful with wind slabs, especially in steep, unsupported and/or convex terrain features.Approach lee and cross-loaded slopes with caution.

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

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 2

Loose Wet

Loose wet activity will probably be limited to solar aspects Friday, but even brief periods of sun could produce loose wet avalanches surprisingly quickly. This activity is expected to pick up as temperatures continue to warm this weekend.

Loose avalanches may start small but they can grow and push you into dangerous terrain.Avoid exposure to steep, sun exposed slopes, especially when the solar radiation is strong.Back off slopes as the surface becomes moist or wet with rising temperatures.

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

Elevations: Treeline, Below Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 2

Valid until: Mar 15th, 2019 2:00PM