Susono boasts a year-around average temperature of 13.8°C, peaking at 24.9°C in August, its warmest month, and dipping to an average low of 3.0°C in January, the coolest. Rainfall averages at 94.4mm annually, with July, August, September seeing the heaviest showers and December being the driest month.
Month | Temperature (Celcius) | Rainfall (mm) |
| January | 3.0 | 75.7 |
| February | 4.0 | 82.0 |
| March | 8.0 | 92.5 |
| April | 13.2 | 91.4 |
| May | 17.6 | 94.0 |
| June | 21.3 | 109.2 |
| July | 24.7 | 115.6 |
| August | 24.9 | 115.6 |
| September | 20.5 | 115.6 |
| October | 14.8 | 98.8 |
| November | 9.0 | 88.9 |
| December | 5.0 | 53.3 |