平年値（日ごとの値）
 |
 |  |
 |  |  |
 |  |
 |  |  |  |  |
八丈島（東京都) 12月 平年値（日ごとの値） 主な要素
| 要素 | 降水量 (mm) | 平均気温 (℃) | 最高気温 (℃) | 最低気温 (℃) | 日照時間 (時間) | 全天日射量 (MJ/㎡) | 平均雲量 | 降雪の深さ合計 (cm) | 最深積雪 (cm) |
|---|---|---|---|---|---|---|---|---|---|
| 統計期間 | 1991～ 2020 | 1991～ 2020 | 1991～ 2020 | 1991～ 2020 | 1991～ 2020 | 1991～ 2009 | 1991～ 2009 | 1991～ 2009 | 1991～ 2009 |
| 資料年数 | 30 | 30 | 30 | 30 | 30 | 19 | 19 | 19 | 19 |
| 1日 | 7.8 | 14.9 | 17.8 | 12.2 | 3.3 | 7.2 @ | 6.9 @ | 0 @ | --- @ |
| 2日 | 7.7 | 14.7 | 17.6 | 12.0 | 3.3 | 7.2 @ | 6.8 @ | 0 @ | --- @ |
| 3日 | 7.6 | 14.6 | 17.5 | 11.8 | 3.3 | 7.2 @ | 6.8 @ | 0 @ | --- @ |
| 4日 | 7.5 | 14.4 | 17.3 | 11.7 | 3.3 | 7.2 @ | 6.8 @ | --- @ | --- @ |
| 5日 | 7.4 | 14.2 | 17.1 | 11.5 | 3.3 | 7.2 @ | 6.7 @ | --- @ | --- @ |
| 6日 | 7.3 | 14.0 | 17.0 | 11.3 | 3.3 | 7.2 @ | 6.7 @ | 0 @ | --- @ |
| 7日 | 7.2 | 13.9 | 16.8 | 11.1 | 3.3 | 7.2 @ | 6.7 @ | --- @ | --- @ |
| 8日 | 7.0 | 13.7 | 16.6 | 10.9 | 3.3 | 7.2 @ | 6.7 @ | --- @ | --- @ |
| 9日 | 6.9 | 13.5 | 16.5 | 10.8 | 3.3 | 7.2 @ | 6.7 @ | 0 @ | --- @ |
| 10日 | 6.7 | 13.4 | 16.3 | 10.6 | 3.3 | 7.2 @ | 6.7 @ | --- @ | --- @ |
| 11日 | 6.6 | 13.2 | 16.1 | 10.5 | 3.3 | 7.2 @ | 6.8 @ | 0 @ | --- @ |
| 12日 | 6.5 | 13.0 | 16.0 | 10.3 | 3.3 | 7.2 @ | 6.8 @ | --- @ | --- @ |
| 13日 | 6.4 | 12.9 | 15.8 | 10.2 | 3.3 | 7.2 @ | 6.8 @ | 0 @ | --- @ |
| 14日 | 6.3 | 12.8 | 15.6 | 10.0 | 3.3 | 7.1 @ | 6.9 @ | --- @ | --- @ |
| 15日 | 6.2 | 12.6 | 15.5 | 9.9 | 3.2 | 7.1 @ | 6.9 @ | --- @ | --- @ |
| 16日 | 6.1 | 12.5 | 15.4 | 9.8 | 3.2 | 7.0 @ | 6.9 @ | 0 @ | --- @ |
| 17日 | 6.1 | 12.4 | 15.2 | 9.7 | 3.2 | 7.0 @ | 7.0 @ | --- @ | --- @ |
| 18日 | 6.1 | 12.3 | 15.1 | 9.6 | 3.2 | 6.9 @ | 7.0 @ | 0 @ | --- @ |
| 19日 | 6.0 | 12.2 | 15.0 | 9.5 | 3.2 | 6.9 @ | 7.1 @ | 0 @ | --- @ |
| 20日 | 6.0 | 12.1 | 14.9 | 9.4 | 3.2 | 6.9 @ | 7.1 @ | 0 @ | --- @ |
| 21日 | 5.9 | 12.0 | 14.8 | 9.3 | 3.2 | 6.9 @ | 7.1 @ | 0 @ | --- @ |
| 22日 | 5.9 | 11.9 | 14.8 | 9.2 | 3.2 | 6.9 @ | 7.1 @ | 0 @ | --- @ |
| 23日 | 5.8 | 11.8 | 14.7 | 9.1 | 3.2 | 6.9 @ | 7.1 @ | 0 @ | --- @ |
| 24日 | 5.7 | 11.7 | 14.6 | 9.0 | 3.2 | 6.9 @ | 7.1 @ | 0 @ | --- @ |
| 25日 | 5.7 | 11.6 | 14.5 | 8.9 | 3.2 | 6.9 @ | 7.1 @ | 0 @ | --- @ |
| 26日 | 5.6 | 11.5 | 14.4 | 8.8 | 3.1 | 6.9 @ | 7.1 @ | 0 @ | --- @ |
| 27日 | 5.5 | 11.4 | 14.3 | 8.7 | 3.1 | 6.9 @ | 7.1 @ | 0 @ | --- @ |
| 28日 | 5.4 | 11.3 | 14.2 | 8.6 | 3.1 | 6.8 @ | 7.1 @ | 0 @ | --- @ |
| 29日 | 5.3 | 11.2 | 14.1 | 8.5 | 3.1 | 6.8 @ | 7.1 @ | 0 @ | --- @ |
| 30日 | 5.3 | 11.1 | 13.9 | 8.4 | 3.1 | 6.8 @ | 7.1 @ | 0 @ | --- @ |
| 31日 | 5.2 | 11.0 | 13.8 | 8.3 | 3.0 | 6.8 @ | 7.1 @ | --- @ | --- @ |
- 「@」の付いた値は、参考値です。平年差や平年比に利用できません。