旬ごとの値
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室蘭（胆振地方) 1981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 | -1.3 | 0.4 | 3.4 | 01 | -2.8 | 08 | -2.9 | -4.6 | 07 | -1.1 | 02 | 7 | 0 | 10 | 0 | 5 | 0 | 0 | 0 | 3.8 | 68 | 36 | 05 | |
| 中旬 | -2.0 | 0.1 | 0.7 | 19* | -1.2 | 20 | -4.0 | -5.3 | 14 | -3.2 | 11 | 10 | 0 | 10 | 0 | 3 | 0 | 0 | 0 | 3.8 | 73 | 41 | 14 | |
| 下旬 | -3.8 | -2.3 | 1.0 | 24 | -4.7 | 27 | -5.7 | -8.0 | 26 | -3.1 | 24 | 11 | 0 | 11 | 0 | 10 | 0 | 0 | 0 | 3.4 | 74 | 47 | 25* | |
| 上旬 | -1.3 | 0.1 | 1.8 | 04 | -2.1 | 09 | -3.0 | -5.1 | 08 | -1.6 | 03 | 9 | 0 | 10 | 0 | 4 | 0 | 0 | 0 | 4.2 | 75 | 51 | 07 | |
| 中旬 | -0.9 | 1.0 | 2.8 | 16 | -1.5 | 11 | -2.7 | -4.8 | 18 | -1.1 | 15 | 8 | 0 | 10 | 0 | 3 | 0 | 0 | 0 | 4.7 | 81 | 53 | 20 | |
| 下旬 | -4.6 | -2.7 | -1.6 | 23 | -3.4 | 24 | -6.0 | -7.3 | 27* | -5.0 | 23 | 8 | 0 | 8 | 0 | 8 | 0 | 0 | 0 | 3.0 | 68 | 20 | 26 | |
| 上旬 | -2.2 | -0.1 | 3.2 | 03 | -2.8 | 01 | -4.3 | -6.4 | 10 | -1.2 | 04 | 8 | 0 | 10 | 0 | 5 | 0 | 0 | 0 | 3.8 | 71 | 38 | 05 | |
| 中旬 | 1.4 | 4.1 | 8.5 | 19 | -0.9 | 11 | -1.2 | -5.8 | 11 | 2.3 | 19 | 3 | 0 | 8 | 0 | 1 | 0 | 0 | 0 | 5.3 | 78 | 43 | 18 | |
| 下旬 | 0.8 | 3.1 | 5.9 | 31* | 0.5 | 25 | -1.1 | -2.7 | 24 | 0.7 | 21 | 2 | 0 | 8 | 0 | 0 | 0 | 0 | 0 | 5.0 | 77 | 39 | 24 | |
| 上旬 | 5.1 | 8.7 | 11.8 | 04 | 4.8 | 02 | 2.2 | -0.4 | 01 | 3.4 | 09 | 0 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 6.2 | 71 | 28 | 08 | |
| 中旬 | 4.1 | 7.3 | 9.9 | 17 | 4.8 | 20 | 1.9 | -0.1 | 15 | 4.0 | 11 | 0 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 6.2 | 76 | 29 | 13 | |
| 下旬 | 9.0 | 12.8 | 16.8 | 24 | 8.4 | 21 | 5.4 | 4.2 | 21 | 7.1 | 24 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 7.9 | 70 | 26 | 28 | |
| 上旬 | 8.5 | 11.8 | 16.8 | 01 | 7.8 | 03 | 5.6 | 4.4 | 09 | 7.1 | 01 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 9.0 | 81 | 24 | 05 | |
| 中旬 | 7.0 | 10.0 | 13.6 | 20 | 6.0 | 18 | 4.6 | 2.8 | 16 | 6.5 | 20 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 8.3 | 84 | 53 | 20 | |
| 下旬 | 9.3 | 12.2 | 18.7 | 22 | 8.5 | 28 | 6.7 | 4.6 | 30 | 11.5 | 22 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 9.4 | 80 | 41 | 31 | |
| 上旬 | 9.4 | 12.2 | 14.5 | 02 | 9.4 | 08* | 7.8 | 5.7 | 01 | 8.7 | 09 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 10.6 | 90 | 51 | 03 | |
| 中旬 | 11.5 | 14.2 | 20.0 | 13 | 11.4 | 20 | 10.2 | 7.7 | 20 | 11.7 | 13 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 12.7 | 93 | 64 | 13 | |
| 下旬 | 13.4 | 16.0 | 23.2 | 26 | 9.3 | 22 | 10.9 | 7.7 | 22* | 13.8 | 25 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 13.4 | 87 | 46 | 24 | |
| 上旬 | 15.1 | 18.0 | 23.7 | 07 | 13.4 | 04* | 13.0 | 11.1 | 04* | 15.7 | 08 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 16.0 | 94 | 63 | 07 | |
| 中旬 | 20.3 | 23.8 | 27.5 | 19 | 20.7 | 16* | 17.5 | 14.8 | 12 | 21.6 | 20 | 0 | 0 | 0 | 0 | 0 | 4 | 0 | 0 | 20.8 | 88 | 72 | 18* | |
| 下旬 | 19.6 | 23.4 | 27.8 | 31 | 20.6 | 28 | 17.3 | 15.5 | 23 | 20.2 | 21 | 0 | 0 | 0 | 0 | 0 | 3 | 0 | 0 | 20.6 | 90 | 68 | 24 | |
| 上旬 | 20.6 | 23.7 | 30.4 | 03* | 18.8 | 08 | 18.5 | 15.9 | 08 | 23.1 | 02 | 0 | 2 | 0 | 0 | 0 | 3 | 2 | 0 | 21.2 | 87 | 56 | 06 | |
| 中旬 | 19.0 | 21.5 | 23.6 | 13 | 18.2 | 18 | 17.4 | 16.6 | 14 | 18.3 | 20 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 20.1 | 92 | 71 | 13 | |
| 下旬 | 19.5 | 22.2 | 24.5 | 28 | 17.9 | 22 | 17.4 | 15.6 | 22 | 18.7 | 27 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 19.7 | 87 | 49 | 28 | |
| 上旬 | 16.7 | 19.6 | 21.4 | 08 | 16.6 | 03 | 14.3 | 12.5 | 07 | 16.4 | 09 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 15.2 | 80 | 51 | 07 | |
| 中旬 | 16.4 | 19.5 | 21.0 | 19 | 17.9 | 13 | 13.4 | 11.9 | 15 | 14.8 | 14* | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 14.5 | 78 | 54 | 17 | |
| 下旬 | 16.5 | 19.4 | 21.4 | 27 | 14.5 | 29 | 13.9 | 7.0 | 28 | 17.3 | 25 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 15.4 | 80 | 47 | 29 | |
| 上旬 | 14.3 | 17.3 | 19.4 | 08 | 14.5 | 10 | 11.3 | 8.9 | 10 | 14.1 | 08 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 11.9 | 72 | 43 | 04 | |
| 中旬 | 12.3 | 15.2 | 17.9 | 12 | 12.9 | 15 | 9.1 | 6.5 | 20 | 11.8 | 11 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 10.0 | 68 | 39 | 11 | |
| 下旬 | 9.8 | 12.7 | 16.7 | 22 | 8.3 | 24 | 6.3 | 3.0 | 24 | 12.7 | 22 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 8.6 | 69 | 33 | 30 | |
| 上旬 | 4.2 | 6.5 | 13.4 | 03 | 1.7 | 07 | 2.0 | -4.0 | 08 | 6.4 | 03 | 1 | 0 | 2 | 0 | 0 | 0 | 0 | 0 | 5.4 | 63 | 44 | 07* | |
| 中旬 | 4.2 | 6.8 | 9.3 | 19 | 1.3 | 17 | 1.1 | -2.2 | 17* | 4.7 | 19 | 1 | 0 | 3 | 0 | 0 | 0 | 0 | 0 | 5.6 | 67 | 44 | 16* | |
| 下旬 | -0.1 | 2.1 | 6.6 | 23 | -2.3 | 30 | -2.0 | -5.7 | 28 | 1.0 | 23 | 4 | 0 | 7 | 0 | 3 | 0 | 0 | 0 | 4.1 | 66 | 43 | 24* | |
| 上旬 | 0.5 | 2.6 | 6.3 | 05 | -0.5 | 01 | -1.4 | -3.9 | 03 | 1.8 | 04 | 3 | 0 | 9 | 0 | 1 | 0 | 0 | 0 | 4.2 | 65 | 45 | 10* | |
| 中旬 | 2.2 | 4.3 | 8.2 | 12 | -1.1 | 14 | 0.1 | -3.9 | 14 | 3.1 | 12 | 2 | 0 | 5 | 0 | 1 | 0 | 0 | 0 | 5.1 | 71 | 46 | 18* | |
| 下旬 | 1.8 | 4.4 | 8.1 | 23 | 0.6 | 24 | -1.3 | -5.9 | 24 | 2.7 | 22 | 3 | 0 | 7 | 0 | 0 | 0 | 0 | 0 | 4.7 | 66 | 40 | 26 | |