Chamonix takes more than 20mm of rain today at 14 degrees, then dries out completely. By Tuesday the valley climbs past 28 degrees. That is a swing of over ten degrees in two days. Zermatt follows the same pattern, a touch cooler up high. The trails stay greasy. Pack a light waterproof shell for the wet morning and grippy soles for the mud that lingers once the sun returns.
Waterproof jackets ↗