| 2025年 | 2026年 | 平年値 | |
| 4-5 | 16.7 | 17.5 | 15.1 |
| 4-6 | 17.3 | 17.8 | 15.3 |
| 4-7 | 15.9 | 17.6 | 15 |
| 4-8 | 15.8 | 17.2 | 14.9 |
| 4-9 | 15.7 | 17.3 | 15.2 |
| 4-10 | 15.8 | 17.2 | 15.2 |
| 4-11 | 16.3 | 17.5 | 15.5 |
| 4-12 | 16.8 | --- | 15.6 |
| 4-13 | 17.6 | 18 | 16.1 |
| 4-14 | 17.7 | 18.3 | 16.6 |
| 4-15 | 17.5 | 18.2 | 16.3 |
| 4-16 | 17.2 | 17.6 | 16.4 |
| 4-17 | 17.5 | 17 | 16.8 |
| 4-18 | 17.5 | 17.4 | 16.7 |
| 4-19 | 17.5 | 17.6 | 16.9 |