Avalanche Forecast

Issued: Apr 5th, 2019 3:00PM

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

Avalanche Canada ghelgeson, Avalanche Canada

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There is quite a bit of uncertainty with forecast snowfall amounts and wind speed this weekend. This forecast is based on around 20 cm of snow falling Friday night. If less than 10 cm of snow falls, then alpine danger should be moderate.

Summary

Confidence

Low - Timing, track, or intensity of incoming weather system is uncertain

Weather Forecast

The weather models are having a pretty tough time getting a handle on the current weather pattern and even the professional meteorologists are pulling out their hair. The freezing levels are thought to be fairly accurate, but the wind and precipitation values should be taken as a suggestion at best.FRIDAY NIGHT: Strong to extreme southwest wind, freezing level around 1000 m, 5 to 15 mm of precipitation expected which could translate to 5 to as much as 20 cm of snow in favored locations.SATURDAY: Broken cloud cover, freezing level rising to 1500 m, moderate to strong south/southeast wind, trace to 10 cm of snow. 2 to 20 mm of precipitation Saturday night which could produce significant snowfall.SUNDAY: Overcast, freezing level around 1200 m, strong south/southwest wind, 2 to 10 cm of snow possible.MONDAY: Overcast, freezing level holding around 1200 m, moderate to strong south/southwest wind, 0 to 5 cm of snow.

Avalanche Summary

There have been no recent avalanche observations in the region. If you're out this weekend we'd love it if you would submit what you're seeing to the Mountain Information Network.

Snowpack Summary

Storm snow falling through the weekend is unlikely to bond well to the mix of old surfaces that include both crust and surface hoar. This will likely only be a problem at and above treeline. Below treeline the snowpack is isothermal throughout much of the forecast region.Previously, sun exposed slopes in the alpine and all aspects at treeline and below were becoming moist to wet during the heat of the day. Dry snow may remain on north-facing slopes in the alpine. In these locations, 50-100 cm of snow sits on a layer of facets (sugary snow) that was buried around March 10th.

Problems

Storm Slabs

An icon showing Storm Slabs
As much as 20 cm of snow could fall Friday night accompanied by strong to extreme wind. Fresh slabs are not expected to bond well to the old snow surface, at least not initially. New snow will need some time to settle and stabilize.
Dial back your terrain choices if you are seeing more than 20 cm of new snow.Fresh snow may rest on a touchy weak layer, don't let good riding lure you into complacency.Watch for rapidly changing conditions during periods of heavy loading from new snow, wind, or rain.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 2

Valid until: Apr 6th, 2019 2:00PM