Normally average temperatures in Siena in July is 21. Through the month the highs are about 27 with low of 19 celsius. The table below includes more detail:
| Month | Degrees Celsius |
|---|---|
| Temperature | 21 |
| High Temperature | 27 |
| Low Temperature | 19 |
| Sunshine Per Day | 10 |
Useful Links: Siena Weather: Average Weather & Yearly Climate