01Plan in Phases
Good planning happens in phases, starting days before and continuing to the moment you leave the parking lot. It is not rigid — it includes flexibility for changing conditions.
Certainty rises as your options run out
Schematic 0–100 index, not measured data — the two curves illustrate the tradeoff, not real percentages. Lock the go/no-go calls in the amber window, before certainty is complete.
Lock the big go/no-go calls in the narrow window where you finally know enough but haven't yet spent your options — the day before and the morning of. Wait for full certainty and your bailouts are already gone.
02Step 1: Choose Your Objective (3-7 days before)
Match the route to your group fitness, technical ability, and experience. Research with guidebooks, trip reports, route databases, topo maps, GPX tracks, and local knowledge. Gather: distance and vertical, estimated time, trailhead/parking, approach conditions, max slope angles and aspects, avalanche exposure, escape routes, and available huts.
03Step 2: Terrain Analysis (2-3 days before)
Study topo maps (1:25,000 ideal). Identify **slope angles** (count contour lines; use shading tools like CalTopo or Gaia GPS), **aspects** (sun/wind implications), and terrain features (ridges, bowls, gullies, cliff bands). Plan safe travel corridors that minimize time in avalanche terrain, and identify multiple descent options and safe regrouping zones.
Where slab avalanches release
The heart of the curve, containing the 38° peak. Maximum slab exposure — the default 'step back' band when danger is Considerable or higher.
Illustrative dry-slab frequency vs. angle (peak set to 100 at 38°). Caps are the reduction-method ceilings by EAWS danger level. Educational only.
04Step 3: Weather & Avalanche Forecasts (1-2 days before)
Check mountain weather (freezing levels, precip, wind, visibility, trend) and the avalanche forecast (danger rating, problems, elevation bands, aspects, likelihood and size).
Consider postponing if danger is Considerable (3)+, after heavy snow/rain, with strong winds building slabs, rapid warming, poor visibility, or extreme cold.
05Step 4: Detailed Planning (day before)
Timing: alpine starts (5-7am) are common; estimate ~300-400m vertical/hour ascent and add a 25-50% buffer. Set a firm turnaround time.
Navigation: offline maps, marked waypoints, GPX tracks, compass bearings, backups.
Gear: beacon/probe/shovel (test the beacon!), layers for the forecast, food/water + extras, first aid, communication, emergency bivy, headlamp.
Communication plan: share your route and expected return with someone not going.
How long is that climb, really?
Add 20-40% for transitions, breaks, navigation and group size.
Moving time only — add the descent and your transitions. The Munter unit = horizontal km + vertical m ÷ 100, divided by your rate. An estimate, not a guarantee; conditions and judgement always rule.
06Steps 5-6: Go/No-Go and Continuous Reassessment
The morning of: recheck weather and the (daily-updated) avalanche forecast, confirm with partners, do a group beacon check at the trailhead, and review the plan.
During the tour, monitor red flags (recent activity, whumpfing, shooting cracks, heavy loading), weather changes, and group dynamics. Set decision points in advance where you will reassess and potentially turn around.
Will you be off the face before it goes?
Illustrative day plan. The deadline is when a sun-exposed face starts to go wet — pull it earlier on south aspects. Set a turnaround at the trailhead and honour it, summit or not. Educational only; the bulletin and your judgement always rule.
07Build Flexibility & Avoid Common Mistakes
Always carry options: Plan A (ideal), Plan B (less exposure), Plan C (low-angle), Plan D (go home).
Common mistakes: summit fever, underestimating time, ignoring forecasts, poor communication, no bailout options, and overestimating abilities.
08Sources & further reading
Sources & further reading. This guide reflects the consensus of the major avalanche-safety organisations and the standard references. Always defer to your local daily avalanche bulletin and hands-on training over any single article:
- Werner Munter, “3×3 Lawinen” — the 3×3 filter and reduction method behind structured trip planning
- **EAWS** — the danger scale and bulletin reading that anchor a plan
- **SLF** — terrain, weather and bulletin science
- **Avalanche.org** — trip-planning resources and education
- Bruce Tremper, “Staying Alive in Avalanche Terrain” — terrain selection and human factors
Key takeaways
- Plan in phases, starting 3-7 days out and reassessing up to the trailhead and throughout the tour.
- Study topo maps for slope angles, aspects, and terrain traps to find safe travel corridors.
- Check both weather and avalanche forecasts and be willing to postpone on red flags.
- Set a firm turnaround time and add a 25-50% time buffer; tours take longer than expected.
- Build flexibility with Plan A/B/C/D and share your plan and return time with someone not on the tour.
Frequently asked questions
How far in advance should I start planning a ski tour?+
Choose your objective 3-7 days before, do terrain analysis 2-3 days out, review forecasts 1-2 days before, finalize logistics the day before, and make a final go/no-go decision the morning of the tour.
What slope angles are avalanche terrain?+
Roughly 30-45 degrees is the primary avalanche terrain. Use slope-angle shading tools and count contour lines (closer = steeper), and watch for terrain traps below steeper slopes.
How do I estimate how long a tour will take?+
Use about 300-400m of vertical per hour on the ascent, add time for breaks, transitions, and route-finding, then add a 25-50% buffer.