Barnhart, Missouri has a humid subtropical climate with hot summers and cold winters. The area receives an average of 43 inches of rainfall annually, with the majority occurring in the spring and summer months. The Big River runs through Barnhart, providing ample opportunity for fishing, kayaking, and canoeing. The river is also a popular destination for camping and hiking, with several parks and trails in the area, including the Big River Trail and the Rockford Beach Park. The hydrology constituents in the area include the Big River, which is monitored for water quality, sediment, and flow by the Missouri Department of Natural Resources. Overall, Barnhart offers a variety of outdoor recreation opportunities for visitors and locals alike.