旬ごとの値
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室蘭（胆振地方) 2021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 | -5.5 | -3.5 | -1.1 | 07 | -7.4 | 01 | -6.9 | -9.6 | 01 | -5.3 | 07 | 10 | 0 | 10 | 0 | 10 | 0 | 0 | 0 | 2.8 | 67 | 47 | 01 | |
| 中旬 | -1.9 | 0.7 | 6.1 | 16 | -4.4 | 19 | -4.7 | -7.9 | 19 | 0.8 | 13 | 8 | 0 | 9 | 0 | 5 | 0 | 0 | 0 | 4.0 | 73 | 44 | 18 | |
| 下旬 | -0.6 | 2.0 | 5.6 | 27 | -2.6 | 31 | -3.2 | -5.6 | 31 | -0.7 | 25 | 5 | 0 | 11 | 0 | 3 | 0 | 0 | 0 | 4.6 | 78 | 48 | 28 | |
| 上旬 | -3.1 | -0.1 | 5.2 | 06 | -6.4 | 03 | -6.0 | -9.3 | 03 | -0.7 | 06 | 8 | 0 | 10 | 0 | 4 | 0 | 0 | 0 | 3.8 | 74 | 52 | 04 | |
| 中旬 | 0.5 | 3.3 | 5.9 | 20 | -2.4 | 17 | -2.3 | -5.1 | 17* | 1.4 | 15 | 4 | 0 | 9 | 0 | 1 | 0 | 0 | 0 | 5.2 | 80 | 49 | 12 | |
| 下旬 | -2.2 | 0.5 | 5.6 | 28 | -3.4 | 24 | -4.9 | -6.8 | 24 | -2.7 | 21 | 7 | 0 | 8 | 0 | 4 | 0 | 0 | 0 | 3.9 | 74 | 46 | 21 | |
| 上旬 | 0.7 | 4.5 | 12.0 | 05 | -0.1 | 03 | -2.4 | -5.2 | 07* | 1.3 | 05 | 4 | 0 | 8 | 0 | 1 | 0 | 0 | 0 | 5.1 | 77 | 43 | 08 | |
| 中旬 | 4.0 | 8.3 | 14.2 | 15 | 4.6 | 13 | 0.7 | -1.7 | 13 | 2.5 | 18 | 0 | 0 | 3 | 0 | 0 | 0 | 0 | 0 | 5.8 | 72 | 30 | 15 | |
| 下旬 | 6.0 | 10.3 | 14.7 | 31 | 4.4 | 21 | 2.9 | -0.4 | 21 | 5.5 | 24 | 0 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 7.6 | 80 | 30 | 27 | |
| 上旬 | 4.7 | 8.9 | 13.2 | 01 | 6.3 | 09 | 1.7 | -1.4 | 09* | 4.5 | 04 | 0 | 0 | 2 | 0 | 0 | 0 | 0 | 0 | 6.6 | 79 | 33 | 10 | |
| 中旬 | 7.2 | 11.2 | 13.8 | 12 | 8.3 | 14 | 4.0 | 1.2 | 14 | 6.4 | 17 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 7.7 | 76 | 24 | 20 | |
| 下旬 | 8.1 | 13.5 | 19.0 | 24 | 9.9 | 26 | 4.3 | 1.8 | 26 | 7.6 | 29 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 7.1 | 66 | 27 | 24 | |
| 上旬 | 9.9 | 15.0 | 18.4 | 06 | 11.1 | 03 | 6.8 | 4.4 | 03 | 9.0 | 08 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 8.8 | 73 | 38 | 07 | |
| 中旬 | 11.5 | 16.4 | 21.9 | 14 | 11.6 | 16 | 8.1 | 5.3 | 12 | 10.1 | 16 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 11.8 | 87 | 44 | 14 | |
| 下旬 | 12.3 | 15.9 | 18.7 | 26 | 12.2 | 29 | 10.0 | 8.4 | 31 | 11.0 | 21 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 12.6 | 89 | 41 | 26 | |
| 上旬 | 15.3 | 20.7 | 27.2 | 10 | 14.5 | 01 | 11.3 | 8.2 | 01 | 13.3 | 08 | 0 | 0 | 0 | 0 | 0 | 1 | 0 | 0 | 14.0 | 82 | 37 | 10 | |
| 中旬 | 15.8 | 19.3 | 26.1 | 13 | 14.6 | 19 | 13.7 | 11.9 | 20 | 16.4 | 13 | 0 | 0 | 0 | 0 | 0 | 1 | 0 | 0 | 16.1 | 90 | 57 | 13 | |
| 下旬 | 16.8 | 20.4 | 25.9 | 26 | 16.2 | 24 | 14.7 | 13.4 | 21 | 15.9 | 30 | 0 | 0 | 0 | 0 | 0 | 1 | 0 | 0 | 17.5 | 92 | 54 | 26 | |
| 上旬 | 16.9 | 19.0 | 22.9 | 07 | 16.7 | 10* | 15.8 | 14.7 | 04 | 17.4 | 06 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 18.7 | 97 | 73 | 06 | |
| 中旬 | 21.1 | 24.6 | 31.2 | 20 | 18.5 | 11 | 18.4 | 16.0 | 11 | 21.8 | 20 | 0 | 3 | 0 | 0 | 0 | 4 | 2 | 0 | 22.3 | 90 | 57 | 18 | |
| 下旬 | 22.1 | 25.0 | 28.5 | 28 | 22.3 | 23 | 20.2 | 18.2 | 27 | 21.3 | 25 | 0 | 0 | 0 | 0 | 0 | 6 | 0 | 0 | 25.1 | 94 | 60 | 27 | |
| 上旬 | 23.5 | 26.4 | 30.4 | 05 | 19.0 | 10 | 21.4 | 15.9 | 10 | 24.0 | 07 | 0 | 3 | 0 | 0 | 0 | 6 | 3 | 0 | 27.3 | 94 | 69 | 05 | |
| 中旬 | 18.3 | 21.0 | 25.1 | 20* | 18.5 | 14 | 16.7 | 15.8 | 14 | 18.0 | 19 | 0 | 0 | 0 | 0 | 0 | 2 | 0 | 0 | 18.1 | 86 | 63 | 20 | |
| 下旬 | 21.0 | 23.7 | 27.9 | 28 | 20.0 | 25* | 19.1 | 17.8 | 22 | 21.1 | 29 | 0 | 0 | 0 | 0 | 0 | 5 | 0 | 0 | 22.0 | 89 | 54 | 31 | |
| 上旬 | 19.6 | 23.0 | 25.1 | 01 | 20.1 | 08 | 17.1 | 15.5 | 06* | 19.0 | 09 | 0 | 0 | 0 | 0 | 0 | 1 | 0 | 0 | 19.0 | 83 | 59 | 10 | |
| 中旬 | 18.2 | 21.9 | 24.1 | 12* | 20.1 | 15 | 15.3 | 12.7 | 14 | 17.9 | 12 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 16.7 | 79 | 49 | 19* | |
| 下旬 | 18.2 | 21.0 | 23.1 | 23 | 19.6 | 25 | 15.8 | 11.2 | 25 | 18.8 | 22 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 18.0 | 85 | 52 | 25 | |
| 上旬 | 16.3 | 20.2 | 24.6 | 04 | 16.5 | 07 | 13.0 | 9.2 | 07 | 18.7 | 04 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 15.1 | 81 | 42 | 07 | |
| 中旬 | 12.5 | 16.1 | 21.6 | 11 | 9.4 | 17 | 8.9 | 3.6 | 17 | 13.0 | 13 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 11.3 | 76 | 41 | 18 | |
| 下旬 | 10.8 | 14.2 | 17.2 | 25 | 10.8 | 23 | 7.5 | 4.6 | 23 | 10.8 | 26 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 10.3 | 79 | 49 | 24* | |
| 上旬 | 11.6 | 14.8 | 16.0 | 05 | 12.2 | 02 | 8.6 | 6.6 | 06 | 12.3 | 09 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 11.2 | 82 | 52 | 01 | |
| 中旬 | 8.6 | 11.3 | 13.3 | 14 | 8.4 | 20 | 5.7 | 3.8 | 18 | 8.2 | 14 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 7.6 | 67 | 44 | 16* | |
| 下旬 | 6.0 | 8.6 | 14.1 | 22 | 4.0 | 24 | 3.2 | 1.2 | 23 | 6.6 | 22 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 7.3 | 76 | 50 | 28 | |
| 上旬 | 4.7 | 8.1 | 13.3 | 01 | 2.5 | 05 | 1.1 | -2.0 | 05 | 4.6 | 07 | 0 | 0 | 3 | 0 | 0 | 0 | 0 | 0 | 6.9 | 77 | 50 | 08 | |
| 中旬 | 1.7 | 3.8 | 10.8 | 11 | -3.0 | 18 | -0.8 | -7.0 | 18 | 5.4 | 11 | 3 | 0 | 5 | 0 | 1 | 0 | 0 | 0 | 5.4 | 76 | 53 | 16* | |
| 下旬 | -3.1 | -0.7 | 5.3 | 21 | -4.4 | 31 | -5.6 | -8.6 | 31 | -0.6 | 21 | 10 | 0 | 11 | 0 | 6 | 0 | 0 | 0 | 3.7 | 73 | 45 | 26 | |