Kwajalein Atoll, Marshall Islands offers 3 beaches perfect for sunbathing, surfing, swimming, and more. Kwajalein Atoll is known for its World War II shipwrecks and the Ronald Reagan Ballistic Missile Defense Test Site. The best time to travel to Kwajalein Atoll is from December to April, with average air temperatures around 81°F (27°C) and water temperatures near 82°F (28°C). Sandee provides detailed maps, photos, and reviews from fellow beachgoers to help you Choose Your Beach™ and plan your perfect beach vacation!