Rock Island is a small town located in Douglas County, Washington. The region experiences a semi-arid climate, characterized by hot, dry summers and cool, wet winters. Summers are typically sunny and warm, with temperatures ranging from the high 80s to the mid-90s Fahrenheit. Winters are mild, with temperatures averaging in the 30s to 40s. Precipitation is relatively low throughout the year, with most rainfall occurring between October and April.

As for hydrology constituents, Rock Island is located near the Columbia River, which has a significant influence on the town. The river provides ample opportunities for boating, fishing, and other water-based activities. The region is also home to numerous lakes and reservoirs, such as Daroga State Park and Rock Island Pool, which offer additional recreational opportunities.

Outdoor recreation in Rock Island is abundant. The town is surrounded by beautiful natural landscapes, including rolling hills, forests, and rocky terrains. Hiking, camping, and bird-watching are popular activities in the nearby areas. Rock Island is also known for its excellent fishing spots, attracting anglers from all over the region.

In summary, Rock Island, Washington offers a semi-arid climate with hot summers and mild winters. Its proximity to the Columbia River and various lakes provides ample opportunities for water-based activities. The town's scenic surroundings offer diverse outdoor recreation opportunities such as hiking, camping, and fishing.