Glacier National Park Avalanche Forecast

Issued: Mar 23rd, 2021 8:00AM

Mon Mar 22nd Current Conditions
Alpine Moderate Treeline Moderate Below Treeline Moderate
Tue Mar 23rd 2 Day Outlook
Alpine Considerable Treeline Moderate Below Treeline Moderate
Wed Mar 24th 3 Day Outlook
Alpine Moderate Treeline Moderate Below Treeline Moderate

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

Moderate winds will encourage slab development and increase the hazard this afternoon.

Summary

Weather Forecast

A ridge of high pressure will break down later today as a fontal system pushes in from the NW.  A mix of sun and cloud today with an alpine temperature of -7, moderate SW winds and freezing level at 1400m.  The incoming frontal system will deliver 5-10cm of new snow Wednesday with an alpine temperature of -5 and freezing levels around 1400m.

Snowpack Summary

30-45cm of recent storm snow is covering a melt-freeze crust on solar aspects and isolated pockets of surface hoar on polar aspects. Recent high freezing levels have created a moist upper snowpack at lower elevation which is now topped with a breakable crust. Cornices are large and fragile.

Avalanche Summary

A group triggered a skier accidental size 1.5 on the top of Puff Daddy , where the storm slab has gained more cohesion.  Three size 2-2.5 natural avalanches were observed on steep N facing terrain in the highway corridor in the gullies on Mt MacDonald.

Confidence

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

Problems

Wind Slabs

An icon showing Wind Slabs

Likelihood

Likely

Expected Size

1 - 2.5

Moderate winds have coaxed 30-45cm of recent storm snow into a cohesive and reactive slab in exposed areas. This slab sits atop a crust on steep solar aspects and surface hoar on shaded aspects. This layer is reactive to skier triggers.

  • Be careful with wind loaded pockets, especially near ridge crests and roll-overs.
  • Carefully evaluate terrain features by digging and testing on adjacent, safe slopes.

Aspects:

All aspects.

Elevations:

Alpine, Treeline.

Loose Dry

An icon showing Loose Dry

Likelihood

Likely - Possible

Expected Size

1 - 2

Today's weather forecast calls for sunny periods. Although the day is starting off cold, intense spring sun combined with recently deposited snow will lead to loose avalanches on steep solar terrain this afternoon.

  • Minimize exposure to sun exposed slopes when the solar radiation is strong.
  • Recent snow may be more sensitive to human triggering on solar aspects where it sits on sun crust

Aspects:

South East, South, South West, West.

Elevations:

All elevations.

Valid until: Mar 24th, 2021 8:00AM

Forecast Trend

The latest forecast danger ratings, broken down to elevation. See how an elevation is trending.