http://papers.ssrn.com/sol3/papers.cfm?abstract_id=1666550 (Contains link to download full PDF)
_"Psychological evidence predicts that sunny weather is associated with an upbeat mood. Although standard economic theory presumes invariant preferences and full rationality, the finance literature has documented a strong relationship between morning sunshine in the city of a country's stock exchange and daily market index returns. In this paper we examine the effect of different weather conditions on art auction selling prices. Our sample includes art prices at auctions conducted from 1786 to 1909 in England. With respect to the main variables identified by the literature as being associated with agents' moods, we find that the length of daylight duration (from sunrise to sunset) on which the auction is conducted has a significant positive effect on the auction selling prices in all our model specifications. In addition, we find in some specifications direct positive effects of hours of sunshine during the day, precipitation, temperature, and whether the daylight duration increases relative to the previous day, on auction selling prices." _
One of the advantages of having multiple large historical datasets freely available is that they can be combined or cross-referenced to find novel information. Such as that art auctions affected by the weather.