Cold and dry -- get outside. My routine puts my rides around lunchtime, so even with short days I can get out if the roads are dry. If you get cold, take stock of your cold weather gear. May take a few rides where you're an inferno from over-dressing, but take the time to find what works. For example, here today it's partly cloudy and in the low-mid 40s F. I wore full tights, winter jacket, cap w/ ear flap, wool socks, and windstopper gloves.

Cold and wet -- Trainer/rollers. I'm a huge thesufferfest.com fan. Great workouts. I don't bother with the trainer tire; I do have a BikesDirect single-speed I use instead. (shrug)

I'm guessing in Waco you can get outside more often than not (from what I remember living in Dallas), if it were me I'd accept the additional wear on the tire(s) just to be getting some work in.

I also relax my perspective on how often I need to ride. Especially with the Holidays and all.