The best time to visit Alton Bay is during the summer months, from June to August, when the weather is warm and all seasonal attractions are fully operational.During this period, the average daily temperatures range from the mid-70s to low 80s Fahrenheit, making it ideal for enjoying Lake Winnipesaukee and its surrounding activities. The lake is warm enough for swimming, boating, and various water sports. Families will find this time particularly suitable, as most attractions, like the Alton Bay Community Beach and the public docks, are open and bustling with activity.Early fall, specifically September, also offers a pleasant experience for couples. The crowds begin to thin, and the weather remains comfortable, with daytime temperatures often in the 60s and 70s. This period is known for its beautiful foliage, providing a scenic backdrop for leisurely drives or hikes around the lake.