Saint-Joseph, Louisiana is a small town located in Tensas Parish. It experiences a humid subtropical climate characterized by hot, humid summers and mild winters. Average temperatures range from the mid-90s°F (mid-30s°C) during summer to the mid-50s°F (10-15°C) in winter. The area receives around 50 inches (1270 mm) of rainfall annually, with the wettest months being May through September.

Being situated near the Mississippi River, hydrology plays a significant role in Saint-Joseph. The town lies within the Mississippi Alluvial Plain, which offers fertile soil for agriculture. The Mississippi River and nearby lakes provide opportunities for fishing, boating, and other water-based activities.

Outdoor recreation enthusiasts can explore the nearby Tensas River National Wildlife Refuge, which offers various recreational activities such as hunting, fishing, wildlife observation, and hiking. The refuge is known for its diverse habitats and abundant wildlife, including white-tailed deer, turkeys, and migratory birds. Additionally, the town's proximity to the Mississippi River allows for opportunities for riverboat cruises and birdwatching along its banks.

Overall, Saint-Joseph, Louisiana, offers a favorable climate for outdoor activities and is surrounded by natural beauty, providing ample opportunities for recreation and enjoying the region's rich hydrology.