The best time to go to Donnelly, Minnesota, is during the summer months, from June to August, for warm weather and outdoor activities, or in autumn, from September to October, for pleasant temperatures and vibrant foliage.Summer offers the warmest weather, with average daily temperatures often reaching the mid-20s Celsius. This is ideal for enjoying Lake Minnewaska, which is just a short drive away, for swimming, boating, or fishing. The longer daylight hours also provide more time to explore the local area, including the nearby Glacial Lakes State Park, which has walking trails.Autumn provides a different kind of beauty, with cooler, crisp air and stunning displays of red, orange, and gold leaves. The temperatures are usually comfortable for outdoor pursuits, typically ranging from 10 to 20 degrees Celsius.