The best time to visit Mex, Valais, Switzerland, largely depends on whether you're seeking winter sports or summer outdoor activities.
For those interested in skiing, snowboarding, or other winter sports, the period from December to April is ideal. During these months, Mex and the surrounding Valais region are blanketed in snow, offering excellent conditions for hitting the slopes. You'll find ski resorts nearby with a variety of runs for all skill levels, and the crisp mountain air provides a wonderful backdrop for a winter escape.
If hiking, mountain biking, or enjoying the alpine scenery in warmer weather is more your preference, then June to September is the superb time. The snow will have melted from most trails, revealing lush green meadows, blooming wildflowers, and clear mountain lakes. The temperatures are pleasant for outdoor exploration, and cable cars and lifts are typically operating, making it easy to access higher elevations for breathtaking views.
Ultimately, your choice depends on the activities you're hoping to enjoy.