Avalanche Forecast

Issued: Nov 16th, 2017 3:00PM

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

Alberta Parks mike.koppang, Alberta Parks

15-25cm recent new snow. If the forecasted strong SW winds arrive overnight we can expect windslabs to quickly build and the danger push into Considerable in Alpine areas.  Keep an eve on overhead terrain and local weather.

Summary

Confidence

Moderate - Wind speed and direction is uncertain on Friday

Weather Forecast

The snow will taper off overnight giving us a mix of sun and cloud on Friday.  Winds are forecast to increase overnight into the moderate to strong range so we can expect windslabs to rapidly build if the forecaster winds arrive. Temperatures will be around -8C.

Avalanche Summary

A few natural avalanches were observed on N aspects in Alpine terrain.  These slides were sz 1.5-2 and were likely fresh windslabs that had been newly building along ridgelines in Alpine areas.  They occurred on N aspects but ran far down into treeline areas. A few loose dry slides were also observed

Snowpack Summary

15-25cm of new storm snow over the past 36hrs that fell with only light winds (15cm at Highwood and 25cm at Smith Dorried).  Throughout the day winds began to increase out of the SW and windslabs were observed building in Alpine areas. Easy sheers within the HST and a Moderate RP was being observed below the 1031 crust. Still lots of variability of snowpack depths.

Problems

Wind Slabs

An icon showing Wind Slabs
If the forecasted winds arrive, we can expect windslabs to quickly build in open alpine areas. 
Avoid lee and cross-loaded terrain near ridge crests.Be careful with wind loaded pockets while approaching and climbing ice routes.Avoid freshly wind loaded features.

Aspects: North, North East, East, South East.

Elevations: Alpine.

Likelihood

Possible - Likely

Expected Size

1 - 3

Valid until: Nov 17th, 2017 2:00PM