I don't know how official my proclamation is but here we go - "Peak Autumn colors have arrived!" I've checked with sources on both sides of the river and the consensus is that the trees are indeed at full color this weekend (October 24 & 25).
You really can't miss with any of the local roads. Even some of the urban areas are worth a visit. Two of my favorites are Thre Great river Road (topped off with a visit to Fast Eddie's of course) or Highway 94 in St. Charles county. The weather should cooperate this weekend. Even though it will be a little chilly on Saturday you may want to consider a bike ride along the Katy trail.
Enjoy the view!