We're getting ready to head down around the same time, 10/11-10/18. It does look like the rain may move in towards the later 1/2 of the trip, but it's a while off still.
In my experience, the October rains are diffrent than the summer. In the summer you can get the quick and big downpours almost every day, and then it'll be sunny and humid. In October, you can get the lingering semi-tropical systems that just sit over the area with a light but steady rain all day. I'm not exactly a fan of it, but what can you do but make the best of it? I guess I'd rather have drizzling overcast days over a complete washout of the Fort.
If it does rain for a while, for me it's time to sit under the awning and crack open some beers!