Joint Base Lewis McChord, United States offers 1 beach perfect for sunbathing, surfing, swimming, and more. Joint Base Lewis McChord is known for its proximity to Mount Rainier National Park and the Museum of Glass. The best time to travel to Joint Base Lewis-McChord is during the summer months of June to August, when the average air temperature is around 70-80°F and water temperature in nearby lakes is approximately 65-70°F. Sandee provides detailed maps, photos, and reviews from fellow beachgoers to help you Choose Your Beach™ and plan your perfect beach vacation!