Purcells

At upper elevations, where the dry snow sits on a crust, persistent slabs have been propagating widely, are surprisingly deep, and could be triggered by warmth, cornices, or riders.

Remain cognizant that a weak, unpredictable layer continues to lurk near the bottom of the snowpack, avoid thin, rocky start zones and shallow areas with variable snowpack depths.

Check for signs of windslab avalanche danger like shooting cracks, especially near ridgetops and in cross loaded gullies.

• Use caution above cliffs and terrain traps where even small avalanches may have severe consequences.
• Be especially cautious as you transition into wind affected terrain.
• Be alert to conditions that change with aspect and elevation.
• Avoid thin areas like rock outcroppings where you're most likely to trigger avalanches failing on deep weak layers.

Sunday Night

Mostly cloudy. 1-5 cm of snow expected in the alpine. Freezing level 2000 m dropping to 1000 m for the overnight period. Light to moderate southwest ridgetop wind. Treeline high around -3 °C

Monday

Cloudy with afternoon clearing and sun. No new precipitation. Freezing level at 1400 m. Light to moderate southwest ridgetop wind. Treeline high around -1 °C

Tuesday

Clear and sunny becoming cloudy in the afternoon. Possible trace of snow expected nears day end. Freezing level at valley bottom overnight rising to 1600 m. Moderate south east ridgetop wind. Treeline high around 0 °C

Wednesday

Intermittent cloud cover with sunny breaks. 1-5 cm of snow expected. Freezing level around 500 m overnight, rising to 1600 m. Light southwest ridgetop wind. Treeline high around 0 °C

More details can be found in the Mountain Weather Forecast.

On Saturday a widespread natural slab avalanche cycle was observed and reported. These avalanches were very large up to (size 3) and are suspected to be storm snow than ran on a crust buried in early April.

A fatal avalanche occurred on April 15 in the Thunderwater lake riding area, just west of this region. The avalanche was triggered near a rocky area and was very large (size 3). Two riders were caught, one was buried approximately 2 meters deep. Despite immediate extricatio rescue response, the rider did not survive. Any additional information we have on this accident can be found in this MIN

On Friday, near Golden, a small (size 1) naturally trigger wet slab avalanche was observed on a south aspect and failed to ground on smooth shale slopes. Numerous other small (size 1) loose wet avalanches were observed on steep south aspect terrain. Additionally a few storm slab avalanches were trigger on south aspect terrain during a period of warmings and clearing.

We suspect that the weight of a human could still trigger windslab avalanches below ridgetops and in cross-loaded gully features. Also, warm temperatures and intense spring sun can quickly make loose wet avalanches likely.

On Wednesday, west of Golden, a few small, touchy windslab avalanches were reported. They were triggered remotely from 20 meters away, by skiers skinning along a ridge.

If you are getting out in the backcountry, consider making a post on the MIN (Mountain Information Network). You can share riding conditions, avalanche or snowpack observations, or even just a photo or two.

At treeline and above, 15-40 cm of recent snow fell with moderate to strong southwest wind, forming windslabs in leeward terrain and storm slabs. A variety of crust, surface hoar and/or facet layers that were buried in mid March through early April may exist in the upper snowpack. Recent avalanche activity in adjacent regions indicate that these interfaces contributed to the current avalanche problem there. Most professional operations in the forecast area are tracking their own local layer of concern to see if they become active with increasing temperatures, or more load from new rain or snow.

Below treeline, expect to find moist or refrozen surfaces, and shrinking snowpack depths.

The mid snowpack is generally settled and strong, although west of Invermere, some professional operations are still monitoring a layer of weak, feathery surface hoar crystals that was buried in mid January.

The lower snowpack includes a widespread layer of large, weak facets and/or depth hoar crystals. This weak layer has been responsible for several very large and destructive avalanches throughout the season, including one last Thursday.