Mer Rouge is a small town located in Morehouse Parish, Louisiana. It has a humid subtropical climate, characterized by hot and humid summers with frequent thunderstorms, as well as mild winters with occasional freezes. The average annual temperature in Mer Rouge is around 66°F.

Hydrologically, the town is situated near Bayou Bartholomew, which is the longest bayou in the world. This bayou provides a water source for the town and supports various aquatic species. Additionally, Mer Rouge has access to the Boeuf River, which offers fishing and boating opportunities.

Outdoor recreation in Mer Rouge is abundant. The town has several parks and recreational facilities, including the Mer Rouge Park and the Morehouse Recreation District. These locations provide opportunities for sports activities, picnicking, and nature walks. The nearby Chemin-A-Haut State Park, located about 30 miles away, offers camping, hiking trails, fishing, and even a swimming pool.

In summary, Mer Rouge, Louisiana, experiences a humid subtropical climate, is influenced by the presence of Bayou Bartholomew, and provides various outdoor recreation opportunities for residents and visitors alike.