The Alps in the heat: start early, drink early

High summer has the Alpine valleys baking. Chamonix climbs towards 28°C by afternoon this week, and that heat sits on you through the first few hundred metres of any climb. Start at first light. Drink before you feel thirsty, and refill at every fountain you pass. By the time the valley peaks, you want to be on the ridge, not still grinding up the switchbacks. Carry more water than feels sensible.