３か月ごとの値
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八丈島（東京都) 1984年（３か月ごとの値） 詳細（日照・雪・その他）
| 月 | 日照時間(h) | 全天日射量 (MJ/㎡) | 雪(cm) | 雲量 | 大気現象 | ||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 合計 | 日照率 | 各階級の日数 | 降雪 | 各階級の日数（降雪） | 最深積雪 | 各階級の日数（最深積雪） | 平均 | 各階級の日数 | 雪日数 | 霧日数 | 雷日数 | ||||||||||||||||||
| 不照 | 日照率 ≧40% | 平均 | 合計 | 日合計の最大 | ≧3cm | ≧5cm | ≧10cm | ≧20cm | ≧50cm | ≧100cm | 値 | 日 | ≧0cm | ≧1cm | ≧5cm | ≧10cm | ≧20cm | ≧50cm | ≧100cm | ＜1.5 | ≧8.5 | ||||||||
| 値 | 日 | ||||||||||||||||||||||||||||
11～1 | 329.5 | 35 | 8 | 33 | 6.7 | 0 | 0 | 01/29* | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 7.3 | 0 | 31 | 3 | 0 | 16 | |
12～2 | 309.2 | 33 | 8 | 30 | 6.9 | 0 | 0 | 02/29* | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 02/09* | 5 | 0 | 0 | 0 | 0 | 0 | 0 | 7.7 | 0 | 40 | 8 | 0 | 10 |
1～3 | 348.0 | 35 | 11 | 35 | 8.6 | 0 | 0 | 03/22* | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 02/09* | 5 | 0 | 0 | 0 | 0 | 0 | 0 | 8.0 | 0 | 43 | 7 | 0 | 7 |
2～4 | 427.9 | 40 | 10 | 45 | 11.3 | 0 | 0 | 03/22* | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 02/09* | 5 | 0 | 0 | 0 | 0 | 0 | 0 | 7.9 | 0 | 42 | 5 | 2 | 3 |
3～5 | 478.5 | 40 | 12 | 49 | 13.5 | 0 | 0 | 03/22* | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 7.7 | 1 | 42 | 0 | 2 | 3 | |
4～6 | 418.8 | 34 | 16 | 42 | 13.8 | -- | -- | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 8.2 | 1 | 52 | 0 | 6 | 1 | ||
5～7 | 472.5 | 37 | 15 | 46 | 15.2 | -- | -- | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 7.9 | 1 | 48 | 0 | 8 | 1 | ||
6～8 | 596.3 | 47 | 10 | 57 | 16.8 | -- | -- | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 6.8 | 5 | 35 | 0 | 8 | 1 | ||
7～9 | 677.8 | 56 | 1 | 68 | 17.3 | -- | -- | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 5.9 | 6 | 19 | 0 | 4 | 8 | ||
8～10 | 579.5 | 51 | 5 | 61 | 14.3 | -- | -- | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 6.2 | 6 | 24 | 0 | 0 | 8 | ||
9～11 | 436.7 | 42 | 9 | 53 | 10.5 | -- | -- | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 6.9 | 1 | 32 | 0 | 0 | 10 | ||
10～12 | 375.7 | 39 | 12 | 43 | 8.0 | 0 | 0 | 12/30* | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 6.9 | 2 | 37 | 0 | 0 | 2 | |