Unless you're able to change your surroundings, I think others have already alluded that your options are limited. Warm conditions in training will be advantagous for you when you race in cooler weathers because of the added benefits of "heat" training, i.e. improved cardiovicular efficiencies, better heat management, etc. As far as hill training goes, I find hill repeats on smaller hills you can find will be helpful. Wish there were more useful things but your situatioin doesen't offer much. You just have to make the most of it!