Rain affects electoral turnout. Some voters are affected through a direct effect on the cost of voting, others react to changing opportunity costs. In a panel of Norwegian municipalities I find that the second effect dominates as rain on election day increases turnout. Supporters of different parties react differently, causing a one percentage point reduction of the vote share of left wing parties. This provides an exogeneous source of variation to identify the causal effect of party composition on politics. Stronger left wing parties shifts spending from education to kindergartens. Beyond this, there are few causal effects of political composition.