The best time to go to Lake Hopatcong is during the summer months, from June to August, when the weather is warm and all water-based activities are in full swing.During these months, the lake is ideal for swimming, boating, and fishing. The surrounding areas also come alive with outdoor dining options and lakeside events. It's a great time for families to enjoy a holiday, as many resorts and rental properties offer activities suitable for all ages, from watersports to mini-golf.For those who prefer a slightly quieter experience with pleasant weather for hiking and exploring the scenic beauty, late spring (May) and early autumn (September to early October) are also excellent choices.