Avalanche Forecast

Issued: Apr 5th, 2015 8:59AM

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

Avalanche Canada rbuhler, Avalanche Canada

Snowpack and avalanche observations are becoming scarce. If you've been in the backcountry, please tell us what you've seen here on the Mountain Information Network.

Summary

Confidence

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

Weather Forecast

A system to the south of the border will bring unsettled conditions to the region Sunday overnight and Monday. 5-10mm of precipitation is expected with moderate alpine winds from the SE to E. Freezing levels are expected to reach around 1500m on Monday afternoon. On Tuesday, a ridge of high pressure moves over the interior and becomes the dominant feature for the rest of the week. A mix of sun and cloud is expected for Tuesday with light alpine winds and freezing levels reaching around 2000m. On Wednesday, mainly sunny conditions are expected with light alpine winds and freezing levels reaching around 2200m.

Avalanche Summary

Observations are becoming more limited as we enter spring. If you're out in the mountains, please consider posting your observations to our webpage. On Saturday, explosives triggered small wind slabs and thin storm slabs that ran on a melt-freeze crust.  On Friday and Saturday, natural loose dry sluffing was reported from steep terrain. On Monday, it may be possible to trigger new wind slabs in the alpine and exposed areas at treeline. Reverse loading may occur and wind slabs should be expected on all aspects.

Snowpack Summary

Melt-freeze surface conditions exist on sun-exposed slopes.  On shaded slopes, 10-20cm of new snow overlies a thick supportive melt-freeze crust. At higher elevations these accumulations have been blown around by variable winds and new wind slabs may exist on a variety of aspects. The mid-March crust/facet complex is buried around 50cm below the surface. This layer is generally considered dormant while the cooler temperatures prevail. The mid and lower snowpack are strong and well settled.

Problems

Wind Slabs

An icon showing Wind Slabs
New snowfall with moderate winds may form new wind slabs in exposed higher elevation terrain. Watch for triggering in the lee of ridge crests and in gullies.
Travel on ridgetops to avoid wind slabs on slopes below, but be careful with cornices!>Be careful with wind loaded pockets, especially near ridge crests and roll-overs.>

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 2

Valid until: Apr 6th, 2015 2:00PM