The best time to visit Gresham is during the summer months, from June to August, when the weather is warm and ideal for outdoor activities.During this period, you can fully enjoy the natural beauty of the area. The lakes and rivers are great for fishing, boating, and swimming, while the surrounding forests offer excellent opportunities for hiking and wildlife spotting. The longer daylight hours also allow for more time to explore.For those who appreciate cooler temperatures and the stunning display of autumn foliage, September and October are also wonderful times to visit.