月ごとの値
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八丈島（東京都) 1991年（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 | ||||||||||||||||||||||||||||
| 86.7 | 27 | 2 | 10 | 7.2 | 0 | 0 | 23* | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 7.1 | 0 | 7 | 1 | 0 | 6 | ||
| 118.3 | 39 | 2 | 14 | 10.5 | 0 | 0 | 26* | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 6.7 | 1 | 9 | 1 | 0 | 3 | ||
| 111.8 | 30 | 8 | 9 | 10.5 | 0 | 0 | 15 | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 7.4 | 2 | 16 | 1 | 3 | 1 | ||
| 131.8 | 34 | 5 | 10 | 14.0 | -- | -- | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 7.6 | 1 | 14 | 0 | 5 | 1 | |||
| 115.9 | 27 | 6 | 11 | 14.4 | -- | -- | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 7.9 | 1 | 15 | 0 | 4 | 4 | |||
| 80.2 | 19 | 7 | 5 | 12.4 | -- | -- | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 8.9 | 0 | 24 | 0 | 6 | 6 | |||
| 114.8 | 26 | 2 | 10 | 15.6 | -- | -- | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 8.8 | 0 | 23 | 0 | 3 | 9 | |||
| 175.4 | 42 | 2 | 15 | 17.0 | -- | -- | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 7.1 | 0 | 17 | 0 | 0 | 2 | |||
| 107.6 | 29 | 2 | 10 | 12.3 | -- | -- | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 8.2 | 0 | 18 | 0 | 1 | 5 | |||
| 88.3 | 25 | 7 | 8 | 9.0 | -- | -- | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 8.1 | 0 | 18 | 0 | 0 | 4 | |||
| 123.4 | 39 | 1 | 14 | 8.9 | -- | -- | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 6.5 | 0 | 9 | 0 | 0 | 1 | |||
| 112.6 | 36 | 3 | 13 | 7.1 | 0 | 0 | 30* | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 30 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 6.8 | 2 | 10 | 0 | 0 | 2 | |