月ごとの値
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留萌（留萌地方) 2018年（月ごとの値） 詳細（気温・蒸気圧・湿度）
| 月 | 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 | ||||||||||||||
| -3.0 | -0.1 | 5.2 | 15 | -5.5 | 29 | -6.1 | -13.2 | 12 | -0.6 | 08 | 27 | 0 | 31 | 0 | 15 | 0 | 0 | 0 | 4.0 | 81 | 45 | 22* | |
| -5.0 | -1.9 | 1.9 | 23* | -5.9 | 12 | -8.7 | -17.9 | 07 | -2.7 | 10 | 28 | 0 | 28 | 0 | 22 | 0 | 0 | 0 | 3.3 | 77 | 38 | 18 | |
| 1.0 | 4.2 | 16.8 | 28 | -2.6 | 06 | -2.5 | -7.9 | 17 | 6.6 | 28 | 13 | 0 | 26 | 0 | 4 | 0 | 0 | 0 | 5.0 | 75 | 37 | 30 | |
| 5.9 | 10.4 | 22.7 | 30 | 3.4 | 05 | 1.8 | -1.2 | 10 | 9.3 | 30 | 0 | 0 | 6 | 0 | 0 | 0 | 0 | 0 | 6.8 | 73 | 24 | 30 | |
| 11.1 | 15.1 | 25.7 | 23 | 8.9 | 05 | 7.4 | 3.2 | 09* | 14.6 | 31 | 0 | 0 | 0 | 0 | 0 | 2 | 0 | 0 | 10.7 | 81 | 25 | 23 | |
| 15.0 | 19.5 | 27.4 | 29 | 11.1 | 14 | 11.4 | 3.0 | 10 | 17.0 | 29 | 0 | 0 | 0 | 0 | 0 | 4 | 0 | 0 | 14.0 | 81 | 41 | 04 | |
| 19.5 | 23.2 | 33.7 | 29 | 14.3 | 05 | 16.6 | 7.1 | 06 | 24.3 | 30 | 0 | 3 | 0 | 0 | 0 | 9 | 4 | 0 | 20.2 | 88 | 49 | 29 | |
| 19.8 | 23.3 | 27.0 | 22 | 17.7 | 16 | 16.7 | 10.4 | 17 | 20.3 | 22 | 0 | 0 | 0 | 0 | 0 | 10 | 0 | 0 | 19.7 | 85 | 38 | 08 | |
| 17.1 | 21.4 | 27.2 | 07 | 17.3 | 22 | 12.7 | 7.0 | 11 | 20.6 | 05 | 0 | 0 | 0 | 0 | 0 | 4 | 0 | 0 | 15.2 | 78 | 39 | 21* | |
| 11.7 | 15.9 | 20.7 | 06 | 9.7 | 30 | 7.6 | 1.4 | 31 | 13.2 | 01 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 10.6 | 77 | 36 | 09* | |
| 5.3 | 8.5 | 15.3 | 04 | 1.7 | 30* | 2.2 | -4.1 | 30 | 8.8 | 10 | 4 | 0 | 8 | 0 | 0 | 0 | 0 | 0 | 7.1 | 78 | 40 | 28 | |
| -1.0 | 1.6 | 12.0 | 04 | -4.5 | 27 | -3.5 | -9.4 | 27 | 4.0 | 04 | 20 | 0 | 28 | 0 | 10 | 0 | 0 | 0 | 4.4 | 75 | 40 | 19 | |