Siena Yearly Weather Summary
Siena weather is characterised by an excellent temperate climate, with weather that is mild through most of the year and generally avoids the worst extremes of hot or cold that can be found elsewhere in Italy. Siena has four seasons: spring (March to May), summer (June to September), autumn (October to November) and winter (December to February). Summertime in Siena rarely gets as hot and sticky as other parts of the country, peaking around 31°C. Winters usually avoid the harshest cold, with temperatures around 10°C.
During the summer months, from May till September, weather in Siena remains hot and humid with the average high of 30°C. Although temperature may appear somewhat hot during this season, occasional rainfall often comes to make the surrounding comfortable for the tourists. The average low temperature, which hardly falls below mid teens, makes the evenings really amazing. July is considered as the hottest month of the year with the average high of 33°C. In fact, Siena is a year round destination, tourists may visit the well decorated city whenever they like.
Winter comes in late October and lasts till February in Siena. During this period the maximums can reach 18°C although the low may fall below 2°C. January, the coldest month of the year, sees not more than 2°C of average low. Infrequent snowfall and a little rain often occur to make the climate worsened during this period. Usually, Siena receives a very poor level of sunshine throughout the season. Moreover, things may become unpredictable when the skies remain overcast.