Avalog
Register
Get forecast notifications
Create an account to receive email notifications when forecasts are published.
Register
Login
Archived

Avalanche Forecast

Mar 1st, 2018–Mar 2nd, 2018
Alpine
3: Considerable
The avalanche danger rating in the alpine will be considerable
Treeline
3: Considerable
The avalanche danger rating at treeline will be considerable
Below Treeline
2: Moderate
The avalanche danger rating below treeline will be moderate
Alpine
3: Considerable
The avalanche danger rating in the alpine will be considerable
Treeline
2: Moderate
The avalanche danger rating at treeline will be moderate
Below Treeline
2: Moderate
The avalanche danger rating below treeline will be moderate
Alpine
3: Considerable
The avalanche danger rating in the alpine will be considerable
Treeline
2: Moderate
The avalanche danger rating at treeline will be moderate
Below Treeline
2: Moderate
The avalanche danger rating below treeline will be moderate

Regions: South Rockies.

A strong southeast flow is expected to bring more snow Thursday night into Friday. Amounts are uncertain but expect to find new storm slabs building especially at upper elevations.

Confidence

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

Weather Forecast

TONIGHT: Snow. Accumulation 5-15. Ridge wind moderate, east. Temperature near -8. Freezing level lowering to valley bottom.FRIDAY: Cloudy, snow. Accumulation 5-15 cm. Ridge wind light, northeast. Temperature near -4. Freezing level 600 m.SATURDAY: Mainly cloudy, light flurries. Accumulation 2-5 cm. Ridge wind light, northeast. Temperature near -6. Freezing level 600 m.SUNDAY: Mix of sun and cloud. Ridge wind light, west. Temperature near -6. Freezing level 500 m.

Avalanche Summary

Over the past week there have been reports of both natural and skier triggered loose dry avalanches in steep terrain, as well as skier and explosive triggered storm slab avalanches up to size 1 that were reported on Monday.Last weekend there were two reports of snowmobilers triggering a size 1.5 and size 2 wind slab releases on northeast to east aspects between 2000-2100 m in the Window mountain area.

Snowpack Summary

About 15-30 cm of new snow now covers previously wind-scoured, westerly slopes and old hard and soft wind slabs on leeward, easterly alpine and treeline slopes. Beneath these old wind slabs lies a well-settled mid-pack. The lower snowpack is weak with two primary concerns that are generally widespread:1) A widespread weak layer from mid-December composed of facets, crusts, and surface hoar that is 100-150 cm deep.2) A rain crust with sugary facets buried in late November near the bottom of the snowpack.

Avalanche Problems

Storm Slabs

New snow and wind may form touch storm slabs particularly on lee and cross-loaded slopes at and above treeline.
Be cautious as you transition into wind affected terrain.If triggered, the wind slabs may step down to deeper layers, resulting in large avalanchesWatch for signs of instability such as whumpfing, or cracking.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood: Possible - Likely

Expected Size: 1 - 2.5

Deep Persistent Slabs

Deeply buried weak layers are most likely to be triggered from thin or variable snowpack areas; or with a large load, like a cornice fall.
Avoid steep convexities or areas with a thin or variable snowpack.Pay attention to overhead hazards like cornices which could easily trigger the deep persistent slab.

Aspects: All aspects.

Elevations: All elevations.

Likelihood: Unlikely - Possible

Expected Size: 2 - 3.5