Swollen ankles can be a symptom of a heart problem, where blood isn't properly pumped away from them. In cold weather your body closes off the smaller capillary vessels (to preserve heat) but they're opened up (to lose excess heat) in warmer weather; that could affect your circulation.
It would be wisest to consult your GP as (even if the problem isn't directly related to your heart) your symptoms suggest a circulatory disorder of some sort (e.g. high blood pressure).
The foregoing paragraphs are based upon knowing people who've experienced problems with swollen ankles (including my father, who had an enlarged heart, and several people with high blood pressure) but this might also be relevant:
http://www.knowsley.n...o-z/s/swollen-ankles/
Chris