Questions about Trexlertown Preserve

Hello,

I'm going to be visiting Schnecksville for Thanksgiving and will be about 3 miles from the Nature Preserve and want to ride. A couple of questions. The weather forecast is for rain on Tuesday and Wednesday. How is trail drainage? Will it be rideable or should I avoid it. Assuming they are rideable, can I do it on a rigid flat bar cross bike with fat tires? I'm headed elsewhere after Schnecksville and want a more versatile bike than my Specialized FSR Xc that I would usually ride. Any thoughts would be appreciated.

Dan