Riddle, Oregon is a small town located in Douglas County, within the South Umpqua River Valley. The climate in Riddle is classified as Mediterranean, characterized by hot, dry summers and mild, wet winters. Summers typically see temperatures ranging from the mid-80s to mid-90s Fahrenheit, while winter temperatures hover around the mid-40s. Precipitation is evenly distributed throughout the year, with an annual average of around 40 inches.

The hydrology constituents in Riddle are mainly influenced by the South Umpqua River, which flows through the town. The river provides opportunities for fishing, particularly for trout and steelhead. Additionally, Riddle is surrounded by various creeks and streams that also offer fishing opportunities.

For outdoor enthusiasts, Riddle offers several recreational opportunities. The South Umpqua River provides opportunities for boating, kayaking, and swimming during the summer months. The surrounding forests and mountains offer trails for hiking, mountain biking, and wildlife viewing. Nearby forests also provide opportunities for hunting during specific seasons.

In summary, Riddle, Oregon experiences a Mediterranean climate with hot summers and mild winters, and its hydrology is dominated by the South Umpqua River. Outdoor recreation opportunities in the area include fishing, boating, hiking, mountain biking, and hunting.