Dashboard Regions Weather Stations Radar Alerts Glossary
Contact About
Log In

Register for an account and never miss a forecast again!

Register

Avalanche Forecast

Archived

Jan 8th, 2022–Jan 9th, 2022

Alpine
Natural avalanches possible, human triggered probable.
Treeline
Natural avalanches possible, human triggered probable.
Below Treeline
Natural avalanches possible, human triggered probable.
Alpine
Natural avalanches possible, human triggered probable.
Treeline
Natural avalanches unlikely, human triggered possible.
Below Treeline
Natural avalanches unlikely, human triggered possible.
Alpine
Natural avalanches possible, human triggered probable.
Treeline
Natural avalanches unlikely, human triggered possible.
Below Treeline
Natural avalanches unlikely, human triggered possible.

Regions

South Rockies.

Wind will impacted any loose snow, pay attention to avalanche conditions that change with aspect and elevation.

Confidence

Moderate - Uncertainty is due to how the snowpack will react to the forecast weather.

Weather Forecast

Saturday night: Cloudy with isolated flurries, up to 5 cm. Strong to extreme SW to NW ridgetop wind. Treeline low around -16 °C and rising. 

Sunday: Mostly sunny. Moderate to strong SW to NW wind. Increasing temperatures with a treeline high around -2 °C. Sun, daytime warming, and possible inversion will push temperatures to 0 °C this evening for elevations above 2000 m.

Monday: Sunny. Moderate SW wind. Treeline high around -1 °C.

Tuesday: Incoming flurries, 5 cm. Moderate WSW wind. Treeline high around -1 °C.

Avalanche Summary

On Friday, explosives and skiers easily triggered storm slab avalanches to size 1.5.

On Wednesday, explosive control work produced numerous loose dry and thin wind slab avalanches in alpine terrain. These avalanches started small but entrained mass in tracks, growing to size 2.5 and running up to 1300m. It is worthy to note that no deep slabs were triggered.

On Monday and Tuesday, natural, explosive and skier triggered storm slabs and loose dry avalanches size 1-2 were observed out of NE-SE aspects in the alpine.

The persistent slab problem has produced sporadic and spotty activity in the South Rockies and nearby regions. The most recent avalanche in the region was Dec 31, when explosives triggered a size 2.5 wind slab avalanche that stepped down to the persistent slab layer on a SE aspect near treeline. Otherwise, persistent slab activity has not been observed in the region since before Christmas. A few recent notables from surrounding regions feature in our latest blog, Photos of recent persistent slab avalanches in the southern interior.

Snowpack Summary

Another 10 cm arriving Saturday morning brough last weeks storm totals 30-60 cm. Strong southwest to southeast winds have developed more reactive deposits around convex and lee features. This recent snow covered a hard, faceted snow surface which formed during cold temperatures, and may take a little time to bond. Sun and warm temperatures on Sunday may turn steep solar aspects moist in the afternoon and encourage loose, wet avalanches.

The most notable layer of concern in the snowpack is a crust that was formed in early December and is now typically down 80-150 cm. The most recent avalanche on this layer was a week ago but sporadic activity has been observed in neighboring regions in the past week. This layer has created a tricky low likelihood, high consequence scenario which is best managed through conservative terrain choices and disciplined backcountry travel techniques.

Terrain and Travel

  • Seek out wind sheltered terrain below treeline where you can avoid wind slabs and find great riding.
  • Be aware of the potential for large avalanches due to the presence of a persistent slab.
  • Avoid shallow, rocky areas where the snowpack transitions from thick to thin.

Problems

Wind Slabs

Wind Slab avalanches are the release of a cohesive layer of snow (a slab) formed by the wind. Wind typically transports snow from the upwind sides of terrain features and deposits snow on the downwind side. Wind slabs are often smooth and rounded and sometimes sound hollow, and can range from soft to hard. Wind slabs that form over a persistent weak layer (surface hoar, depth hoar, or near-surface facets) may be termed Persistent Slabs or may develop into Persistent Slabs.

Persistent Slabs

Persistent Slab avalanches are the release of a cohesive layer of snow (a slab) in the middle to upper snowpack, when the bond to an underlying persistent weak layer breaks. Persistent layers include: surface hoar, depth hoar, near-surface facets, or faceted snow. Persistent weak layers can continue to produce avalanches for days, weeks or even months, making them especially dangerous and tricky. As additional snow and wind events build a thicker slab on top of the persistent weak layer, this avalanche problem may develop into a Deep Persistent Slab.