Siena weather in January
January in Siena: cold, a little rain, with clean air — a good time to visit.
#11 of 12 months in Siena · #558 of 897 destinations to visit in January · comfort 66/100 (tier C)
Updated June 2026 · climate normals from ERA5 reanalysis
Traveller notes on Siena in January
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Siena climate normals — January
| Daytime high | 9°C / 48°F | 🧥 cold |
|---|---|---|
| Nighttime low | 1°C / 33°F | |
| Rainfall | 60 mm / 2.4 in | 🌦 some rain |
| Rainy days | 8 days | |
| Humidity | 83% | 💦 very humid |
| Dew point | 2°C / 36°F | |
| Sunshine | 6.4 h/day | |
| Daylight | 9.4 h | |
| Wind | 13 km/h / 8 mph | |
| Snowfall | 4.4 cm / 1.7 in | |
| Air quality (US AQI) | 33 | 🍃 good |
Monthly averages from ERA5 reanalysis. AQI is the mean US Air Quality Index for the month.
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Siena in January — FAQ
- Is January a good time to visit Siena?
- January in Siena: cold, a little rain, with clean air — a good time to visit. It ranks #11 of 12 months for Siena on SeasonMap's comfort score (66/100).
- What is the weather like in Siena in January?
- In January, Siena averages a daily high of 8.7°C and a low of 0.5°C, with about 60.3 mm of rain over roughly 8.4 rainy days.
- What is the air quality in Siena in January?
- Siena has a mean US Air Quality Index of about 33 in January.
- Does it snow in Siena in January?
- Siena sees roughly 4.4 cm of snowfall in January.