露点/露点温度Td，在空气中水汽含量不变， 保持气压一定的情况下， 使空气冷却达到饱和时的温度称露点温度，简称露点，单位用℃或℉表示。实际上也就是水蒸气与水达到平衡状态的温度。
| 相对湿度 | 环境温度时的露点温度 | ||||||||||
| -7 | -1 | 4 | 10 | 16 | 21 | 27 | 32 | 38 | 43 | 49 | |
| 90% | -8 | -2 | 3 | 8 | 14 | 19 | 25 | 31 | 36 | 42 | 47 |
| 85% | -8 | -3 | 2 | 7 | 13 | 18 | 24 | 29 | 35 | 40 | 45 |
| 80% | -9 | -4 | 1 | 7 | 12 | 17 | 23 | 28 | 34 | 39 | 43 |
| 75% | -9 | -4 | 1 | 6 | 11 | 17 | 22 | 27 | 33 | 38 | 42 |
| 70% | -11 | -8 | -1 | 4 | 10 | 16 | 20 | 26 | 31 | 36 | 41 |
| 65% | -11 | -7 | -2 | 3 | 8 | 14 | 19 | 24 | 29 | 34 | 39 |
| 60% | -12 | -7 | -3 | 2 | 7 | 13 | 18 | 23 | 26 | 33 | 38 |
| 55% | -13 | -8 | -4 | 1 | 6 | 12 | 16 | 21 | 27 | 32 | 37 |
| 50% | -14 | -9 | -5 | -1 | 4 | 10 | 15 | 19 | 25 | 30 | 34 |
| 45% | -16 | -11 | -6 | -2 | 3 | 8 | 13 | 18 | 23 | 28 | 33 |
| 40% | -17 | -12 | -8 | -3 | 2 | 6 | 11 | 16 | 21 | 28 | 31 |
| 35% | -19 | -13 | -9 | -5 | -1 | 4 | 9 | 14 | 18 | 23 | 28 |
| 30% | -20 | -16 | -11 | -7 | -2 | 2 | 7 | 11 | 16 | 21 | 25 |