Avalanche Forecast Northwest Coastal

Date Issued: Valid Until:

Avalanche Canada ghelgeson, Avalanche Canada

Avalanche Forecast

Sun Apr. 14th ยท 3:00PM

Alpine

Danger Ratings Moderate

Treeline

Danger Ratings Moderate

Below Treeline

Danger Ratings Low
Storm Slabs Storm Slabs
Loose Wet Loose Wet

Alpine

Danger Ratings Moderate

Treeline

Danger Ratings Moderate

Below Treeline

Danger Ratings Low

Alpine

Danger Ratings Considerable

Treeline

Danger Ratings Moderate

Below Treeline

Danger Ratings Low
Winter is coming... back and new snow has likely improved riding quality, especially in the alpine. But new snow and wind are likely forming fresh slabs, so you need to carefully check out the bond of the new snow before committing to your line.

Confidence

Moderate - Timing, track, or intensity of incoming weather system is uncertain on Tuesday

Weather Forecast

A fairly juicy pattern is setting up that should deliver significant snow and wind to the Coast beginning Monday night carrying on through at least Friday. These systems are pretty convective which makes it difficult to pin down accurate snowfall amounts, but it looks like winter is coming, back, at least to the alpine over the next few days.SUNDAY NIGHT: Freezing level around 500 m, light to moderate southwest wind, trace to 3 cm of snow possible. MONDAY: Broken cloud cover, freezing level rising to around 1000 m, light to moderate southwest wind, trace to 3 cm of snow possible. TUESDAY: Overcast, freezing level around 1000 m, moderate to strong southwest wind, 5 to 15 cm of snow possible, with another 5 to 10 cm possible Tuesday evening.WEDNESDAY: Broken cloud cover, freezing level around 1200 m, moderate to strong southwest wind, 1 to 5 cm of snow possible during the day with 5 to 15 cm possible Wednesday night.

Avalanche Summary

Ne new avalanche activity to report from yesterday, but most of the snow fell late in the day.We received a great MIN report on Friday. It details a few avalanche occurrences including a size 3 on an east facing slope and lots of loose wet activity from steep terrain.

Snowpack Summary

The region received 5 to 20 cm of snow Saturday into Saturday night. There is now about 20 cm of dry snow on high elevation north facing slopes and a 5 to 10 cm melt freeze crust on all other aspects. As we enter into mid-April we're dealing with a classic warm snowpack. At and below treeline the snowpack is becoming isothermal. We're tracking the April 4th crust which is down 20 to 80 cm below the surface on high elevation north facing slopes. Surface hoar and facets have been observed on this crust and it continues to produce sudden planar results in snowpack tests. We have not heard of any activity on this interface recently, but this week's cycle of storms have potential to activate it. Digging deeper, north facing alpine terrain also has a layer of facets down approximately 100 cm below the surface which are thought to be dormant at this time.

Problems

Storm Slabs

Storm Slabs

Watch for fresh slab development, especially in high elevation north facing features where human triggering is most likely near ridgecrest. High elevation south and west slopes could produce heavy sluffing as the new snow slides on a crust.

Avoid freshly wind loaded features, especially near ridge crests, roll-overs and in steep terrain.Look for signs of instability: whumphing, hollow sounds, shooting cracks, and recent avalanches.Recent new snow may be hiding windslabs that were easily visible before the snow fell.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Likely - Possible

Expected Size

1 - 2

Loose Wet

Loose Wet

Periods of sunshine may initiate a loose wet avalanche cycle in the new snow. The likelihood of loose avalanches increases as temperatures warm throughout the day and/or if the sun comes out for a prolonged period of time.

A moist/wet snow surface, pinwheeling and natural avalanches all indicate a weakening snowpack.Loose avalanches may start small but they can grow and push you into dangerous terrain traps.Avoid exposure to steep, sun exposed slopes, especially when the solar radiation is strong.

Aspects: South East, South, South West.

Elevations: Alpine, Treeline.

Likelihood

Likely - Possible

Expected Size

1 - 2