Monza boasts a year-around average temperature of 13.5°C, peaking at 23.5°C in July, its warmest month, and dipping to an average low of 2.6°C in January, the coolest. Rainfall averages at 83.2mm annually, with October seeing the heaviest showers and January being the driest month.
Month | Temperature (Celcius) | Rainfall (mm) |
| January | 2.6 | 47.0 |
| February | 4.8 | 58.4 |
| March | 9.3 | 73.2 |
| April | 13.8 | 88.6 |
| May | 18.2 | 86.1 |
| June | 21.6 | 111.5 |
| July | 23.5 | 68.6 |
| August | 22.8 | 85.3 |
| September | 19.4 | 72.6 |
| October | 13.9 | 120.4 |
| November | 8.2 | 113.5 |
| December | 4.0 | 73.2 |