Our editors at Localcycling.com will always suggest jumping into one of the many area cyclocross events remaining on the calendar (check out the Kansas Cycling Association link in the upper right hand corner). A hard 30-60 minutes on the blend of turf and road, with a little running will definitely warm one up.
BUT there are other ways to stay fit during the winter (while staying quite toasty). Local coach Gina Poertner is starting up her indoor cycling training events beginning on Dec. 3rd. The classes/workouts are offered twice weekly. Check out the details here.