Saltillo, Texas is a small town located in the northeastern part of the state. It experiences a humid subtropical climate characterized by hot and humid summers and mild winters. Summers in Saltillo are typically long and hot, with temperatures often reaching the high 90s°F (mid 30s°C), while winters are mild with temperatures averaging in the 50s°F (10-15°C).

In terms of hydrology, Saltillo is situated near the Sulphur River, which is known for its diverse aquatic life and recreational activities. The river provides opportunities for fishing, boating, and kayaking, attracting outdoor enthusiasts.

Aside from the Sulphur River, Saltillo and its surrounding areas offer various outdoor recreation opportunities. The region is known for its scenic landscapes and is ideal for hiking, camping, and birdwatching. There are several parks and nature reserves nearby, such as Cooper Lake State Park and Lake Bob Sandlin State Park, which offer opportunities for picnicking, swimming, and wildlife observation.

In conclusion, Saltillo, Texas boasts a humid subtropical climate, proximity to the Sulphur River, and a variety of outdoor recreation opportunities, making it an appealing destination for nature lovers and outdoor enthusiasts.