Ask these questions during tour planning, at the time of actual route selection on the day of the tour, and when traversing individual slopes during a tour.

Check the three key factors that affect avalanche risk, snow+weather, terrain, people, at every step asking at least the questions in the table below. The answers to these questions and your own competence and knowledge determines your decisions.

There is no absolute standard. What might be safe for a highly skilled group that takes every precaution and modifies its behaviour and route according to the risks would be absolute folly for an inexperienced group quite unable to do this.

If in doubt, assume the worst case.

There is no such thing as zero risk. Hoar frost and graupel layers can persist in the snowpack all winter long with a correspondingly high slab avalanche risk throughout the winter even though all other factors might suggest otherwise. Check.

Route Selection Checklist

Snowpack/WeatherTerrainPeople
Tour planningPlan in checkpoints and alternatives.Avalanche Bulletin.
Weather forecast.
Information from locals.
1:25,000 Map.
Gradients from map
Guide books.
Photos.
Own knowledge.
Size of group ?
Motivations?
Expectations?
Skill level?
Equipment.
Who responsible?
Route selectionUse checkpoints and alternatives.Avalanche Bulletin Risk Factor and type of risk.
First day after new snow? Fresh snow still on the trees?
Temperature?
Actual snow conditions. WUMM sounds?
Wind direction?
Drifting?
Avalanches?
Oddities.
Visibility.
Check terrain on sight.
Gradient.
Terrain traps.
Existing ski tracks
-how many? How old?
Orientation, steepness of risk slopes.
Reports from others.
Who’s in my group?
Competitive atmosphere?
Time plan for tour?
Itinerary left with someone?
Backmarker.
Appoint possible search leaders and stress need for discipline.
Check all transceivers transmitting before leaving the hut/car.
Individual slopes during the tourGo / No GoHow much new snow?
Signs of wind?
Lee or windward?
Visibility?
Solar radiation?
Temperature?
Snowpack stability?
Possible slab risk?
Alarm signs?
Actual gradient?
Steepest part of slope?

Risk FactorWhat slope is important?
1on slope nearby
2slope up to 40m away
3over whole slope
4whole slope and runout areas

At factor 3 limit route to 30° slopes maximum.
At factor 4 limit route to 25° slopes maximum.
What’s above me?
What’s below me?,
Convex slope?
Near the ridge?
Any wind pockets?

How many people on the slope?
Do not be pressured by presence of other groups.
Group discipline?
Tiredness?
Technique?
Spacing?
Think!

 

Risk Assessment Checklist

Low riskSome riskModerate riskConsiderable riskHigh riskHigh risk
Snowfall
Depth of new snow0cm10cm20cm40cm80cm160cm+
Time since last snow4 weeks2 weeks1 week4 days2 days1 day
Wind
StrengthNo windLight windStrong wind, Heavy driftingStorm
Lee or windward?Windward slopeWind dunes, Wind ripplesLee slope
Time since last wind4 weeks2 weeks1 week4 days2 days< 1 day
Temperature
during snowfall0° C-2° C-4° C-8° C-15° C-25° C
Temperature changeIncreased to 0° C for >2daysMidday, Full sunIncreased to 0°C in last hours.
Föhn
Snowpack
What surface below new snowOld consolidated snowFine powderPowderCrustFirm IceLoose snow, Hoar frost
Old snow structureStable fine crystal layersFrozen snowpack (becomes wet and dangerous
in sun)
Wet ground (grass), Warm, wet snowpackGraupel or Hoar frost between layers.
Terrain
Gradient of slope<20°<30°>30°> 40°
Form of slopeFlat, No bumps or gulleysConcave, Many old ski tracksConvexNear crest of ridge, Gulley, Funnel
Group
Fully trained, Analytical, DisciplinedOther groups skiing powder nearbyExcitable, Excited, Competitive, Targets


Last updated on 9th July 2018