The best time to visit Qassiarsuk is during the summer months, from June to August, when the weather is mildest and the days are long.
During this period, temperatures are at their highest, typically ranging from 50°F to 60°F (10°C to 15°C), making outdoor activities comfortable. The ice in the fjords has usually melted, allowing for easier boat access to historical sites and surrounding areas. This is also when you'll experience the midnight sun, with nearly 24 hours of daylight, which provides extended opportunities for exploration.
This time is particularly good for travelers interested in exploring the Norse ruins, such as Erik the Red's original settlement. The mild weather allows for pleasant hikes to viewpoints overlooking the fjord and the sheep farms.