up here around gainesville/winder it takes about 2-3 days of sun to totally dry out. check out
http://gainesvillesorba.org/wordpress/ for chicopee woods/ gsc mtn bike trail, and
http://yaba.homestead.com/ for fort yargo. these are the trails i frequent, since theyre all pretty close to me. idk where you ride, but theres probably a website for them if theyre kept up by a club, and will let you know if theyre open or not. as much fun as it is to ride through the mud and much and get filthy, it ultimately screws up the trails