旬ごとの値
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留萌（留萌地方) 1991年（旬ごとの値） 詳細（気温・蒸気圧・湿度）
| 月 | 旬 | 気温(℃) | 蒸気圧 (hPa) | 湿度(％) | ||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 日平均 | 最高気温 | 最低気温 | 各階級の日数（平均） | 各階級の日数（最低） | 各階級の日数（最高） | |||||||||||||||||||
| 平均 | 平均 | 最高 | 最低 | 平均 | 最低 | 最高 | ＜0℃ | ≧25℃ | ＜0℃ | ≧25℃ | ＜0℃ | ≧25℃ | ≧30℃ | ≧35℃ | 平均 | 平均 | 最小 | |||||||
| 値 | 日 | 値 | 日 | 値 | 日 | 値 | 日 | 値 | 日 | |||||||||||||||
| 上旬 | -2.1 | 0.4 | 2.5 | 07 | -2.8 | 06 | -5.5 | -10.0 | 06 | -1.1 | 10 | 8 | 0 | 10 | 0 | 4 | 0 | 0 | 0 | 4.4 | 82 | 52 | 03* | |
| 中旬 | -0.5 | 2.3 | 4.3 | 20 | 0.6 | 18* | -3.5 | -7.6 | 19 | 2.5 | 20 | 8 | 0 | 9 | 0 | 0 | 0 | 0 | 0 | 4.5 | 76 | 54 | 17 | |
| 下旬 | -3.0 | 0.1 | 3.2 | 25 | -2.2 | 31 | -6.2 | -10.5 | 23 | -0.9 | 26 | 10 | 0 | 11 | 0 | 6 | 0 | 0 | 0 | 3.7 | 76 | 46 | 22 | |
| 上旬 | -3.9 | 0.1 | 2.4 | 10 | -1.2 | 06 | -7.9 | -11.7 | 01 | -4.5 | 04 | 10 | 0 | 10 | 0 | 4 | 0 | 0 | 0 | 3.8 | 82 | 46 | 01 | |
| 中旬 | -5.3 | -1.8 | 1.0 | 15 | -6.5 | 19 | -10.0 | -20.9 | 20 | -3.8 | 11 | 10 | 0 | 10 | 0 | 6 | 0 | 0 | 0 | 3.0 | 68 | 29 | 20 | |
| 下旬 | -3.2 | 0.3 | 4.1 | 27 | -2.4 | 23 | -7.3 | -10.5 | 25 | -1.6 | 28 | 6 | 0 | 8 | 0 | 5 | 0 | 0 | 0 | 3.8 | 77 | 46 | 25 | |
| 上旬 | -1.5 | 1.4 | 5.5 | 04 | -2.0 | 09 | -4.2 | -9.2 | 09 | 1.8 | 05 | 7 | 0 | 8 | 0 | 4 | 0 | 0 | 0 | 3.9 | 71 | 38 | 10 | |
| 中旬 | -1.8 | 1.5 | 7.7 | 20 | -3.9 | 14 | -5.3 | -15.5 | 15 | 0.0 | 19 | 6 | 0 | 9 | 0 | 3 | 0 | 0 | 0 | 4.0 | 73 | 35 | 11 | |
| 下旬 | 1.3 | 4.6 | 10.0 | 23 | 0.5 | 21 | -2.5 | -4.1 | 23 | -0.2 | 31 | 3 | 0 | 11 | 0 | 0 | 0 | 0 | 0 | 4.5 | 67 | 35 | 27 | |
| 上旬 | 4.5 | 7.5 | 10.4 | 04 | 3.6 | 01 | 1.1 | -1.8 | 01 | 2.9 | 10* | 0 | 0 | 3 | 0 | 0 | 0 | 0 | 0 | 6.4 | 76 | 44 | 01 | |
| 中旬 | 7.0 | 10.6 | 16.1 | 17 | 6.1 | 20 | 3.0 | -0.2 | 20 | 7.9 | 15 | 0 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 6.7 | 68 | 24 | 17 | |
| 下旬 | 7.7 | 11.8 | 17.2 | 26 | 6.8 | 22 | 3.6 | 0.3 | 23 | 7.5 | 29 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 7.8 | 74 | 26 | 28 | |
| 上旬 | 8.6 | 12.3 | 20.0 | 10 | 5.5 | 03 | 4.6 | 0.1 | 04* | 9.3 | 08 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 7.9 | 71 | 29 | 07 | |
| 中旬 | 12.1 | 15.9 | 21.4 | 12 | 12.3 | 14 | 8.1 | 4.8 | 12 | 11.9 | 16 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 10.5 | 75 | 22 | 12 | |
| 下旬 | 13.0 | 17.5 | 25.1 | 24 | 12.1 | 27 | 7.8 | 5.2 | 28 | 10.8 | 25 | 0 | 0 | 0 | 0 | 0 | 1 | 0 | 0 | 10.0 | 68 | 20 | 24 | |
| 上旬 | 15.8 | 20.1 | 25.6 | 01 | 15.2 | 06 | 12.4 | 10.6 | 01 | 15.6 | 10 | 0 | 0 | 0 | 0 | 0 | 1 | 0 | 0 | 14.2 | 80 | 30 | 01 | |
| 中旬 | 15.7 | 19.0 | 23.8 | 12 | 14.3 | 15 | 12.9 | 9.1 | 20 | 15.3 | 12 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 15.7 | 88 | 44 | 20 | |
| 下旬 | 18.4 | 22.1 | 24.8 | 22 | 19.9 | 29 | 15.4 | 12.7 | 21 | 17.2 | 27 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 17.1 | 81 | 57 | 22 | |
| 上旬 | 18.4 | 22.1 | 26.2 | 10 | 19.5 | 02 | 14.8 | 11.9 | 01 | 17.4 | 10 | 0 | 0 | 0 | 0 | 0 | 1 | 0 | 0 | 16.8 | 79 | 47 | 01 | |
| 中旬 | 19.2 | 23.0 | 27.5 | 16 | 19.7 | 13 | 15.8 | 13.4 | 19 | 17.3 | 17 | 0 | 0 | 0 | 0 | 0 | 2 | 0 | 0 | 17.2 | 79 | 39 | 18 | |
| 下旬 | 20.6 | 24.5 | 29.2 | 24 | 19.5 | 28 | 17.8 | 15.9 | 21 | 21.4 | 24 | 0 | 0 | 0 | 0 | 0 | 5 | 0 | 0 | 20.3 | 84 | 49 | 24 | |
| 上旬 | 20.5 | 24.3 | 25.9 | 03 | 23.1 | 05 | 17.4 | 15.1 | 07 | 20.4 | 02* | 0 | 0 | 0 | 0 | 0 | 4 | 0 | 0 | 19.2 | 80 | 53 | 09 | |
| 中旬 | 21.0 | 24.7 | 29.7 | 20 | 21.9 | 12 | 17.8 | 16.5 | 16 | 20.2 | 20 | 0 | 0 | 0 | 0 | 0 | 2 | 0 | 0 | 20.3 | 82 | 55 | 18 | |
| 下旬 | 19.5 | 23.0 | 27.2 | 25 | 20.0 | 27 | 15.5 | 11.1 | 28 | 21.1 | 21 | 0 | 0 | 0 | 0 | 0 | 1 | 0 | 0 | 17.9 | 79 | 41 | 25 | |
| 上旬 | 19.4 | 22.6 | 24.7 | 03 | 19.6 | 10 | 15.9 | 12.8 | 10 | 20.0 | 07 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 18.7 | 83 | 61 | 08 | |
| 中旬 | 16.4 | 21.1 | 23.6 | 19 | 19.2 | 20* | 11.4 | 7.6 | 16 | 16.0 | 12 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 13.4 | 73 | 45 | 16 | |
| 下旬 | 14.7 | 18.4 | 21.4 | 22 | 15.2 | 27 | 10.8 | 8.1 | 26 | 13.1 | 28 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 12.9 | 77 | 40 | 26 | |
| 上旬 | 14.3 | 18.9 | 22.6 | 02 | 16.3 | 05 | 10.1 | 7.6 | 10 | 13.1 | 03 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 11.8 | 73 | 42 | 10 | |
| 中旬 | 12.3 | 15.6 | 18.9 | 17* | 9.7 | 15 | 9.1 | 7.8 | 14 | 12.2 | 13 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 10.9 | 76 | 44 | 20 | |
| 下旬 | 9.5 | 12.7 | 19.3 | 27 | 9.1 | 31 | 5.6 | 1.9 | 25 | 7.9 | 27 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 8.3 | 70 | 40 | 23 | |
| 上旬 | 5.7 | 10.1 | 15.6 | 03 | 1.9 | 05 | 1.7 | -2.6 | 05 | 7.0 | 08* | 1 | 0 | 2 | 0 | 0 | 0 | 0 | 0 | 6.8 | 73 | 44 | 10 | |
| 中旬 | 3.1 | 5.4 | 8.6 | 17 | 1.9 | 15 | 0.5 | -1.3 | 15 | 1.4 | 18 | 0 | 0 | 2 | 0 | 0 | 0 | 0 | 0 | 5.5 | 72 | 44 | 16 | |
| 下旬 | 4.6 | 8.1 | 10.3 | 28* | 1.7 | 24 | 0.2 | -5.2 | 24 | 4.5 | 26 | 2 | 0 | 3 | 0 | 0 | 0 | 0 | 0 | 6.1 | 71 | 42 | 27 | |
| 上旬 | 1.0 | 3.7 | 9.8 | 06 | -3.0 | 10 | -1.8 | -6.2 | 07 | 4.3 | 01 | 4 | 0 | 6 | 0 | 3 | 0 | 0 | 0 | 4.7 | 68 | 41 | 08 | |
| 中旬 | -1.9 | 0.8 | 7.2 | 17 | -4.7 | 12 | -5.1 | -13.4 | 12 | 0.2 | 17 | 6 | 0 | 9 | 0 | 5 | 0 | 0 | 0 | 4.0 | 73 | 45 | 20 | |
| 下旬 | -3.4 | -0.5 | 4.4 | 24 | -3.2 | 30 | -6.9 | -13.3 | 27 | -1.2 | 21 | 9 | 0 | 11 | 0 | 7 | 0 | 0 | 0 | 3.7 | 76 | 45 | 22 | |