Home / Guides / TMB variants and bad weather: Arpette, Lac Blanc, lower options
TMB variants and bad weather: Arpette, Lac Blanc, lower options
Last updated 25 October 2026 · Elom ESSAN, founder of Trekalto
In short
In bad weather or snow, prefer standard routes over Fenêtre d’Arpette or Lac Blanc, which are higher and more committing. Arpette: ref ~14.6 km / +1300 m (measured ~14.4 / +1476), max ~2644 m. Lac Blanc: ref ~9 km / +1100 m (measured ~8.7 / +1265), max ~2365 m. Lifts and shuttles can also shorten a day — check official calendars each year.
Fenêtre d’Arpette (Champex → Trient)
Athletic variant versus the standard Champex → Trient stage (~15.8 km, +750 / −890). Variant reference ~14.6 km / +1300 m; Trekalto measured ~14.4 km / +1476 m; max altitude ~2644 m. In fog, storm, or lingering snow, stay on the lower / standard route.
Lac Blanc (Argentière → Flégère)
Versus the standard stage ~9.5 km / +750 / −120: Lac Blanc variant ref ~9 km / +1100 m (measured ~8.7 / +1265), max ~2365 m. Fair weather and fresh legs; otherwise Flégère by the usual path. Lac Blanc is booked off-platform — 2027 booking open dates not announced.
Shortcuts if the day goes sideways
Options named in the Trekalto product: Les Houches–Bellevue gondola, Les Chapieux → Ville des Glaciers shuttle, La Fouly → Champex bus, Flégère / Brévent lifts. Summer 2026 example only: Bellevue about 6 June–13 September 2026; adult one-way about €18.90, return about €23.90 (label as 2026). For 2027: compagniedumontblanc.fr and chamonix.com.
Build buffer into the plan
A 9- or 11-day format leaves more room to postpone a variant. In 7 days, a lost day is hard to recover. Work the scenario in the planner and read the method.
FAQ
Arpette in bad weather?
Not recommended. High col (~2644 m) and significant ascent. Take the standard Champex–Trient route.
Is Lac Blanc mandatory?
No. It is a variant. The standard Argentière → Flégère stage is enough to complete the loop.
Do lifts replace a stage?
They shorten or skip a climb/descent, depending on the section. Check official opening and fares each year — no 2027 guarantee here.
Does Croix du Bonhomme change weather options?
The hut is closed until summer 2029: no shelter at the Contamines–Chapieux col. Plan Nova / Mottets / Chapieux and an adapted day.
Related guides
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Plan my TMBSources: Autour du Mont-Blanc, Compagnie du Mont-Blanc, Chamonix.com, Refuge Croix du Bonhomme, OpenStreetMap copyright. Figures may change; always confirm with the refuge or carrier before you leave. Method: /en/method.