Thermal, United States offers 1 beach perfect for sunbathing, surfing, swimming, and more. Thermal, California, United States, is known for its proximity to the Coachella Valley Music and Arts Festival. The best time to travel to Thermal, United States, is in the spring (March to May) when the average air temperature is around 75°F (24°C) and water temperature is approximately 70°F (21°C). Sandee provides detailed maps, photos, and reviews from fellow beachgoers to help you Choose Your Beach™ and plan your perfect beach vacation!