You can visit Siena during almost any time of the year. Siena has excellent temperate climate and the weather is mild through most of the months. With four seasons like spring, summer, autumn and winter it is neither too hot nor too cold in Siena, as it is other parts of Italy. The mild weather of Siena is best experience in the spring (March to May) and autumn (September to November), when it is the most attractive. It may rain in the months of April and May, but if you love rain, you can see a different Siena during these months. Summers are the most popular with tourists which means that the months of July and August sees Siena most crowded. So choose your best time and head off!