When spring comes and the streets dry out I hang up the winter commuter for 7 months or so. It stays in the hot garage all summer and the tires end up rotten and heat checked real quick. I'm lucky if I can go into a second season with the same set of tires. Incidentally I like Continentals but they are about the worst for drying out.
Any tips on extending the shelf life on these tires? I've even thought about washing them off real good at the end of the season and removing them from the bike and storing them in the house (cooler).
I also realize this is probably not an issue in colder/wetter climates but it gets pretty hot/dry in the California central valley.
Tires will age fairly well if they are kept away from UV and ozone. If you have a washer or a dryer in the garage, the motors will be a source for a small amount of ozone. I found that cleaning tires and wrapping them with saran helped. I have been hanging my tires in my closet in the home....they seem to age very little.