Chamonix heads into the weekend mild and almost dry, with the valley forecast sitting between 12 and 18 °C until Sunday. The catch is fog. Saturday and Sunday both show it in the forecast. Trails you know well look different in grey, and junctions are easy to miss. Carry a charged phone with an offline map and a light windproof layer for the damp air. October days are shorter, so plan to be back down early.
Windproof jackets ↗