October and November are prime months where I fish, but the fishing can be good just about anytime. How are you planning on going after them? Boat, skiff, kayak, wade, guided or self guided? If you have a way to get there, the lakes and flats around Greens and Cotton Bayou in West Matagorda bay offer some great sight casting opportunities. I try to get down there one weekend in October every year. But like someone else said, any coastal marsh should have some fish available during the Autumn. Some marshes are better in higher water conditions and some excel in lower water. Most of the marshes I fish require a kayak, airboat or poling skiff to get the most out of the water.