Archived

Avalanche Forecast

Nov 20th, 2024–Nov 21st, 2024

Alpine

2: Moderate

The avalanche danger rating in the alpine will be moderate

Treeline

2: Moderate

The avalanche danger rating at treeline will be moderate

Below Treeline

1: Low

The avalanche danger rating below treeline will be low

Alpine

2: Moderate

The avalanche danger rating in the alpine will be moderate

Treeline

2: Moderate

The avalanche danger rating at treeline will be moderate

Below Treeline

1: Low

The avalanche danger rating below treeline will be low

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

Regions: Glacier.

Be aware that stubborn wind slabs are present in the Alpine and in open Treeline features.

With limited early season options to ride, overcrowding is an issue. Avoid putting yourself below other groups, and if you are above a party, communicate with them and avoid dumping an avalanche on top of them.

Confidence

Moderate

Avalanche Summary

Wednesday, backcountry reports of rider triggering wind slab from reverse loading winds, on S/SW aspects.

On Tuesday, we had reports of a few rider triggered slabs in the Connaught valley, size 0.5-1.5. The reactivity and distribution of these wind slabs is hard to predict.

Few small natural avalanche along the highway corridor have been observed in the last three days.

Riders are reporting minor sluffing in steep terrain.

Snowpack Summary

24 hours of N/NE winds have formed fresh wind slabs on S/SW terrain. 50 to 70 cm of settling HST sits over the November 9 crust. This crust is present up to 2100 m and higher on solar facing terrain. Moderate winds last week created wind slabs in open terrain and on lee features. These slabs are buried by 10 cm on low density snow. Below Treeline, the snowpack tapers to 40cms or less, making ski outs treacherous! Expect glaciers to have poor coverage and thin bridging.

Weather Summary

A break in the weather Thursday, before the next low pressure system brings strong winds, rising freezing levels and moderate precipitation.

Wed Night: Flurries, Alp low -9*C, light SE winds.

Thurs: Cloudy/Flurries, Alp high -2*C, light SE winds, 1200m FZL

Fri: Flurries, 10-15cm, Alp high -3*C, light SE winds gusting to strong, 1800m FZL

Sat: Flurries, 10-20 cm, Alp High -5*C, light gusting to mod winds, 1400m FZL

Terrain and Travel Advice

Be alert to conditions that change with elevation, aspect, and exposure to wind.
Recent wind has varied in direction, so watch for wind slabs on all aspects.
Carefully evaluate steep lines for wind slabs.

Avalanche Problems

Wind Slabs

Reverse loading winds Tuesday have created fresh slabs on S/SW terrain features in open terrain at Treeline and in the Alpine. Buried wind slabs from weekend winds can be found in exposed terrain. Use caution in steep terrain where a small avalanche could have large consequences.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood: Possible - Likely

Expected Size: 1 - 2.5