Rohnert Park, located in Sonoma County, California, has a mild Mediterranean climate characterized by warm, dry summers and cool, wet winters. Summers average temperatures in the mid-80s°F (around 29°C), while winter temperatures range from the mid-40s°F to high 50s°F (around 7-15°C). The area experiences moderate rainfall, mostly between November to April, with an annual average of around 30 inches (76 cm).

Hydrologically, Rohnert Park lies within the Russian River watershed, which provides water for the region. The river is known for its scenic beauty, and residents can enjoy various recreational activities such as fishing, kayaking, and canoeing. Nearby Lake Sonoma also offers outdoor opportunities, including boating, hiking, and camping.

Rohnert Park itself provides several outdoor recreation spaces, including parks, trails, and golf courses. The popular Foxtail Golf Club offers two 18-hole courses, while the 128-acre Crane Creek Regional Park offers nature trails, picnic areas, and a disc golf course. Residents and visitors can also explore the nearby Sonoma Coast State Park, known for its stunning beaches, hiking trails, and camping facilities.