Avalanche Forecast

Issued: May 2nd, 2014 8:08AM

The alpine rating is below threshold, the treeline rating is below threshold, and the below treeline rating is below threshold. Known problems include Loose Wet, Persistent Slabs and Storm Slabs.

chris gooliaff, Parks Canada

Glacier.

May 2 is the final day for the Winter Permit System. Contact the Visitor Safety staff at Glacier National Park for help with safe trip planning in the spring and summer seasons.

Summary

Weather Forecast

Watch for periods of warming in the form of sun or rain to weaken the surface crusts. If above freezing conditions persist through overnight periods, the poor recovery of surface crusts and further heating may affect deeper layers. Spring storms will undoubtedly bring additional snow to the area, so watch for new wind slabs to form .

Snowpack Summary

Melt/freeze cycles have created surface crusts on all but high North facing slopes. As new snow accumulates over these crusts, watch for storm slab and wind slab problems to arise. Cornices will weaken with warm spring temp's. Overall, expect the snowpack to become less stable during the heat of the day.

Avalanche Summary

As the snowpack continues to warm and lose strength, large avalanche events will occur into the spring and summertime. Cornices will begin to droop and will cause sizeable avalanches as the spring progresses.

Confidence

Problems

Loose Wet

Short bursts of solar heating can rapidly affect the snowpack at this time of year. With warmer temperatures arriving with spring/summer, the sun-effect is amplified and loose avalanches are likely during the heat of the day.

Start and finish early before the surface crusts melt.Avoid exposure to sun exposed slopes.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible - Likely

Expected Size

1 - 3

Persistent Slabs

Sustained heating will weaken the snowpack as the days become warmer., allowing avalanches to step-down to deeper persistent layers. Remember, cornices or smaller avalanches hitting a slope could trigger these serious slabs.

Be aware of the potential for full depth avalanches due to deeply buried weak layers.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible

Expected Size

2 - 3

Storm Slabs

As spring storms continue to bring new snow, watch for storm or wind slabs to develop on surface crusts in the alpine or tree-line.

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible

Expected Size

1 - 2

Valid until: May 3rd, 2014 8:00AM