Siena Weather in May
May in Siena averages 23°C (73°F) during the day and 11°C (52°F) at night. Quite a bit of rainfall is typical this month, with around 74 mm (2.9 in) on average. An umbrella is a good idea.
Rainfall in Siena in May
You can expect rain on roughly 12 days based on historical data, averaging 74 mm (2.9 in) for the month. Rain this month is fairly typical, a standard mix of wet and dry days with no particularly heavy or persistent showers.
Temperature in Siena in May
May is a perfect month in Siena, with 23°C (73°F) during the day and 11°C (52°F) at night. The days can feel warmer than the evenings, so packing for both parts of the day is a good idea. Nights cool down to 11°C (52°F), so a light jacket or extra layer is useful once the sun goes down. On the plus side, the cooler nights make for comfortable sleeping conditions.
Sunshine in Siena in May
The month enjoys around 300 hours of sunshine, creating mostly sunny days with good weather conditions.If you favor pleasant temperatures and minimal rainfall, May is one of the best months to visit Siena.
Check the conditions for any month of the year.
For a detailed overview over the year and the best time to visit Italy, check out our Siena's climate page.
Siena Temperature in May
Min Temperature
11°C (52°F)
Max Temperature
23°C (73°F)
Chance of Rain
39%
Precipitation
74 mm (2.9 in)
Rainy days
12 days
Sunshine
300 hours
Percentage Sunshine
Daily Historical Temperatures
50-year average (1976-2025)
Based on our historical records, temperatures in Siena typically rise from around 21°C (70°F) at the start of May to approximately 25°C (77°F) by the end. Nights are cool, with lows typically ranging from 10°C (50°F) to 13°C (55°F).
Average temperatures in May
Daily Historical Precipitation
50-year average (1976-2025)
Average daily rainfall for each day of the month based on long-term records.
Average precipitation in May
Historical weather for Siena in May
Browse day-by-day weather records for Siena spanning 51 years. Select any month and year to see actual temperatures, rainfall, and conditions recorded on each day.
Siena historical weather extremes in May
Based on weather observations in Siena between 1976 and 2026, these are the recorded extremes during May.
- The hottest May day on record in Siena reached 34°C (93°F) (May 27, 2022).
- The coldest May day was on May 4, 1991, with a maximum of 11°C (52°F).
- Siena registered its coldest May night on May 6, 1987, with temperatures dropping to 2°C (36°F).
- The wettest day in May Siena was on May 21, 2012 with 30 mm (1.2 in) of precipitation.
Best Places in Italy in May
Find out more about the weather in Italy and which places have the best travel conditions in this month. See all of Italy in May →
perfect weather
pleasant
tolerable
unpleasant
poor
What to Wear in Siena in May
For Siena in May, you'll want flexible clothing. It's wise to pack cotton shirts, comfortable shorts, and a pair of jeans for cooler evenings. A light sweater or jacket is useful for air-conditioned spaces (like buses) or unexpected cool moments. Rain is likely on several days, so bring a good rain jacket. And with plenty of sunshine hours, don’t forget sunglasses, sunscreen, and maybe a sun hat.What To Do in Siena in May
We rated the following activities from 1 (least suitable) to 10 (best) to do.
Check the conditions for any month of the year.
For a detailed overview over the year and the best time to visit Italy, check out our Siena's climate page.
See the full Siena climate overview or explore weather in Italy.
