Vaughan Bell passes along a study that bucks the conventional wisdom:

There's a common belief that the weather affects our mood, that we tend to become more depressed in the winter and that summer brings an emotional lift. This has been researched before in small studies that have found inconsistent results but a new study published in Psychiatry Research tested the idea on almost 14,500 people and found no link to weather, while the seasonal effects did not follow the common belief: depression was more common in summer and autumn.