| Average | ||||
| South Dakota | Precipitation | Normal | Temperature | Normal |
| Watertown | ||||
| April | 1.59 | 2.18 | 37.5 | 44.8 |
| May | 0.77 | 3.03 | 51.1 | 57.1 |
| June | 0.93 | 3.53 | 68.1 | 66.8 |
| July | 3.68 | 3.05 | 69.4 | 72.5 |
| August | 2.68 | 2.72 | 66.9 | 70.3 |
| Webster | ||||
| April | 2.62 | 1.84 | 37.5 | 44.5 |
| May | 1.93 | 2.83 | 52.7 | 57.1 |
| June | 1.61 | 3.35 | 68.6 | 66.6 |
| July | 7.32 | 3.20 | 69.7 | 72.2 |
| August | 6.11 | 2.90 | 68.3 | 70.0 |