半旬ごとの値
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八丈島（東京都) 1991年（半旬ごとの値） 詳細（日照・雪・その他）
| 月 | 半旬 | 日～日 | 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 | ||||||||||||||||||||||||||||||
| 第1半旬 | 1～ 5 | 12.4 | 25 | 1 | 1 | 6.0 | -- | -- | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 6.8 | 0 | 2 | 0 | 0 | 0 | |||
| 第2半旬 | 6～10 | 13.8 | 28 | 0 | 2 | 7.4 | 0 | 0 | 06 | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 7.0 | 0 | 0 | 1 | 0 | 1 | ||
| 第3半旬 | 11～15 | 13.6 | 27 | 0 | 2 | 6.9 | 0 | 0 | 15* | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 7.5 | 0 | 1 | 0 | 0 | 2 | ||
| 第4半旬 | 16～20 | 15.8 | 31 | 0 | 2 | 8.0 | 0 | 0 | 18 | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 5.5 | 0 | 1 | 0 | 0 | 1 | ||
| 第5半旬 | 21～25 | 12.7 | 25 | 1 | 2 | 6.3 | 0 | 0 | 23 | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 8.2 | 0 | 2 | 0 | 0 | 2 | ||
| 第6半旬 | 26～31 | 18.4 | 29 | 0 | 1 | 8.4 | -- | -- | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 7.8 | 0 | 1 | 0 | 0 | 0 | |||
| 第1半旬 | 1～ 5 | 21.0 | 40 | 0 | 3 | 10.3 | -- | -- | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 6.7 | 0 | 1 | 0 | 0 | 0 | |||
| 第2半旬 | 6～10 | 21.9 | 41 | 1 | 3 | 10.0 | -- | -- | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 6.2 | 0 | 1 | 0 | 0 | 1 | |||
| 第3半旬 | 11～15 | 24.9 | 46 | 1 | 3 | 11.1 | -- | -- | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 6.2 | 0 | 2 | 0 | 0 | 0 | |||
| 第4半旬 | 16～20 | 14.4 | 26 | 0 | 2 | 9.3 | 0 | 0 | 20* | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 8.0 | 0 | 2 | 0 | 0 | 2 | ||
| 第5半旬 | 21～25 | 17.3 | 31 | 0 | 1 | 9.9 | 0 | 0 | 25* | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 7.9 | 0 | 2 | 1 | 0 | 0 | ||
| 第6半旬 | 26～28 | 18.8 | 55 | 0 | 2 | 13.8 | 0 | 0 | 26 | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 4.7 | 1 | 1 | 0 | 0 | 0 | ||
| 第1半旬 | 1～ 5 | 27.0 | 47 | 1 | 3 | 11.7 | -- | -- | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 5.7 | 0 | 1 | 0 | 0 | 0 | |||
| 第2半旬 | 6～10 | 20.6 | 35 | 2 | 2 | 10.0 | -- | -- | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 6.7 | 1 | 2 | 0 | 0 | 0 | |||
| 第3半旬 | 11～15 | 9.4 | 16 | 2 | 0 | 8.3 | 0 | 0 | 15 | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 7.7 | 0 | 2 | 1 | 0 | 1 | ||
| 第4半旬 | 16～20 | 36.5 | 61 | 0 | 4 | 16.5 | -- | -- | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 5.0 | 1 | 1 | 0 | 0 | 0 | |||
| 第5半旬 | 21～25 | 7.5 | 12 | 1 | 0 | 8.6 | -- | -- | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 9.2 | 0 | 4 | 0 | 1 | 0 | |||
| 第6半旬 | 26～31 | 10.8 | 15 | 2 | 0 | 8.5 | -- | -- | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 9.6 | 0 | 6 | 0 | 2 | 0 | |||
| 第1半旬 | 1～ 5 | 26.9 | 43 | 2 | 3 | 14.5 | -- | -- | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 6.3 | 1 | 2 | 0 | 0 | 0 | |||
| 第2半旬 | 6～10 | 22.7 | 36 | 1 | 2 | 15.1 | -- | -- | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 8.4 | 0 | 3 | 0 | 0 | 1 | |||
| 第3半旬 | 11～15 | 15.9 | 25 | 1 | 1 | 11.8 | -- | -- | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 8.6 | 0 | 3 | 0 | 3 | 0 | |||
| 第4半旬 | 16～20 | 16.5 | 25 | 0 | 1 | 11.6 | -- | -- | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 7.1 | 0 | 2 | 0 | 0 | 0 | |||
| 第5半旬 | 21～25 | 29.7 | 45 | 0 | 2 | 16.1 | -- | -- | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 6.8 | 0 | 0 | 0 | 1 | 0 | |||
| 第6半旬 | 26～30 | 20.1 | 30 | 1 | 1 | 14.7 | -- | -- | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 8.5 | 0 | 4 | 0 | 1 | 0 | |||
| 第1半旬 | 1～ 5 | 30.8 | 46 | 0 | 3 | 18.6 | -- | -- | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 5.5 | 0 | 0 | 0 | 0 | 1 | |||
| 第2半旬 | 6～10 | 15.7 | 23 | 1 | 2 | 13.5 | -- | -- | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 8.6 | 0 | 2 | 0 | 2 | 0 | |||
| 第3半旬 | 11～15 | 15.4 | 22 | 2 | 1 | 12.2 | -- | -- | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 8.4 | 0 | 3 | 0 | 0 | 0 | |||
| 第4半旬 | 16～20 | 33.8 | 49 | 1 | 3 | 17.8 | -- | -- | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 6.1 | 1 | 1 | 0 | 0 | 0 | |||
| 第5半旬 | 21～25 | 9.3 | 13 | 0 | 1 | 13.4 | -- | -- | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 9.3 | 0 | 4 | 0 | 2 | 2 | |||
| 第6半旬 | 26～31 | 10.9 | 13 | 2 | 1 | 11.7 | -- | -- | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 9.2 | 0 | 5 | 0 | 0 | 1 | |||
| 第1半旬 | 1～ 5 | 21.2 | 30 | 1 | 2 | 13.7 | -- | -- | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 8.5 | 0 | 4 | 0 | 2 | 0 | |||
| 第2半旬 | 6～10 | 25.7 | 36 | 0 | 3 | 18.3 | -- | -- | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 7.6 | 0 | 2 | 0 | 0 | 0 | |||
| 第3半旬 | 11～15 | 3.4 | 5 | 2 | 0 | 9.0 | -- | -- | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 9.8 | 0 | 5 | 0 | 1 | 2 | |||
| 第4半旬 | 16～20 | 10.2 | 14 | 1 | 0 | 10.2 | -- | -- | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 9.6 | 0 | 5 | 0 | 1 | 1 | |||
| 第5半旬 | 21～25 | 0.3 | 0 | 3 | 0 | 7.3 | -- | -- | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 10.0 | 0 | 5 | 0 | 1 | 2 | |||
| 第6半旬 | 26～30 | 19.4 | 27 | 0 | 0 | 15.7 | -- | -- | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 7.9 | 0 | 3 | 0 | 1 | 1 | |||
| 第1半旬 | 1～ 5 | 10.8 | 15 | 1 | 1 | 11.1 | -- | -- | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 9.4 | 0 | 4 | 0 | 0 | 2 | |||
| 第2半旬 | 6～10 | 22.6 | 32 | 0 | 2 | 16.8 | -- | -- | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 8.3 | 0 | 3 | 0 | 1 | 1 | |||
| 第3半旬 | 11～15 | 8.3 | 12 | 1 | 0 | 13.5 | -- | -- | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 9.6 | 0 | 5 | 0 | 2 | 0 | |||
| 第4半旬 | 16～20 | 22.8 | 32 | 0 | 2 | 16.9 | -- | -- | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 8.7 | 0 | 4 | 0 | 0 | 3 | |||
| 第5半旬 | 21～25 | 16.6 | 24 | 0 | 1 | 15.5 | -- | -- | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 8.0 | 0 | 3 | 0 | 0 | 0 | |||
| 第6半旬 | 26～31 | 33.7 | 41 | 0 | 4 | 19.0 | -- | -- | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 8.8 | 0 | 4 | 0 | 0 | 3 | |||
| 第1半旬 | 1～ 5 | 43.5 | 64 | 0 | 4 | 22.1 | -- | -- | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 5.1 | 0 | 1 | 0 | 0 | 0 | |||
| 第2半旬 | 6～10 | 37.6 | 55 | 0 | 4 | 19.0 | -- | -- | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 6.2 | 0 | 2 | 0 | 0 | 2 | |||
| 第3半旬 | 11～15 | 46.9 | 70 | 0 | 4 | 22.4 | -- | -- | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 4.3 | 0 | 0 | 0 | 0 | 0 | |||
| 第4半旬 | 16～20 | 5.2 | 8 | 2 | 0 | 9.3 | -- | -- | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 9.7 | 0 | 5 | 0 | 0 | 0 | |||
| 第5半旬 | 21～25 | 22.2 | 34 | 0 | 1 | 15.3 | -- | -- | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 9.3 | 0 | 5 | 0 | 0 | 0 | |||
| 第6半旬 | 26～31 | 20.0 | 26 | 0 | 2 | 14.2 | -- | -- | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 8.1 | 0 | 4 | 0 | 0 | 0 | |||
| 第1半旬 | 1～ 5 | 27.7 | 43 | 0 | 4 | 16.6 | -- | -- | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 7.9 | 0 | 3 | 0 | 0 | 1 | |||
| 第2半旬 | 6～10 | 11.5 | 18 | 0 | 0 | 9.5 | -- | -- | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 7.4 | 0 | 2 | 0 | 1 | 0 | |||
| 第3半旬 | 11～15 | 17.6 | 28 | 0 | 2 | 13.8 | -- | -- | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 9.1 | 0 | 4 | 0 | 0 | 0 | |||
| 第4半旬 | 16～20 | 18.2 | 30 | 2 | 2 | 10.5 | -- | -- | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 8.6 | 0 | 4 | 0 | 0 | 2 | |||
| 第5半旬 | 21～25 | 19.9 | 33 | 0 | 2 | 13.1 | -- | -- | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 8.1 | 0 | 3 | 0 | 0 | 1 | |||
| 第6半旬 | 26～30 | 12.7 | 21 | 0 | 0 | 10.5 | -- | -- | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 8.3 | 0 | 2 | 0 | 0 | 1 | |||
| 第1半旬 | 1～ 5 | 31.2 | 53 | 0 | 4 | 15.2 | -- | -- | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 6.4 | 0 | 1 | 0 | 0 | 0 | |||
| 第2半旬 | 6～10 | 2.4 | 4 | 1 | 0 | 6.3 | -- | -- | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 9.7 | 0 | 5 | 0 | 0 | 2 | |||
| 第3半旬 | 11～15 | 13.4 | 23 | 1 | 1 | 7.9 | -- | -- | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 7.5 | 0 | 2 | 0 | 0 | 1 | |||
| 第4半旬 | 16～20 | 19.6 | 35 | 1 | 2 | 10.8 | -- | -- | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 7.0 | 0 | 2 | 0 | 0 | 1 | |||
| 第5半旬 | 21～25 | 19.2 | 35 | 0 | 1 | 9.9 | -- | -- | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 7.6 | 0 | 2 | 0 | 0 | 0 | |||
| 第6半旬 | 26～31 | 2.5 | 4 | 4 | 0 | 4.7 | -- | -- | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 9.8 | 0 | 6 | 0 | 0 | 0 | |||
| 第1半旬 | 1～ 5 | 17.9 | 33 | 0 | 1 | 9.0 | -- | -- | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 7.0 | 0 | 2 | 0 | 0 | 0 | |||
| 第2半旬 | 6～10 | 21.5 | 40 | 0 | 2 | 10.0 | -- | -- | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 6.9 | 0 | 2 | 0 | 0 | 0 | |||
| 第3半旬 | 11～15 | 11.2 | 21 | 1 | 1 | 6.6 | -- | -- | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 7.0 | 0 | 1 | 0 | 0 | 0 | |||
| 第4半旬 | 16～20 | 24.4 | 47 | 0 | 3 | 9.2 | -- | -- | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 5.7 | 0 | 1 | 0 | 0 | 1 | |||
| 第5半旬 | 21～25 | 29.5 | 58 | 0 | 5 | 10.1 | -- | -- | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 3.6 | 0 | 0 | 0 | 0 | 0 | |||
| 第6半旬 | 26～30 | 18.9 | 37 | 0 | 2 | 8.4 | -- | -- | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 8.7 | 0 | 3 | 0 | 0 | 0 | |||
| 第1半旬 | 1～ 5 | 32.1 | 64 | 0 | 4 | 9.9 | -- | -- | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 4.1 | 2 | 1 | 0 | 0 | 0 | |||
| 第2半旬 | 6～10 | 26.0 | 52 | 0 | 4 | 8.9 | -- | -- | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 6.5 | 0 | 1 | 0 | 0 | 0 | |||
| 第3半旬 | 11～15 | 22.1 | 44 | 0 | 2 | 7.7 | -- | -- | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 6.5 | 0 | 1 | 0 | 0 | 1 | |||
| 第4半旬 | 16～20 | 6.3 | 13 | 1 | 0 | 5.0 | -- | -- | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 6.9 | 0 | 1 | 0 | 0 | 0 | |||
| 第5半旬 | 21～25 | 20.3 | 41 | 0 | 3 | 7.6 | -- | -- | 0 | 0 | 0 | 0 | 0 | 0 | -- | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 8.5 | 0 | 3 | 0 | 0 | 0 | |||
| 第6半旬 | 26～31 | 5.8 | 10 | 2 | 0 | 4.0 | 0 | 0 | 30* | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 30 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 8.4 | 0 | 3 | 0 | 0 | 1 | |