What is Dew Point?
The dew point is the temperature at which air becomes saturated with moisture and water vapor begins to condense into liquid water (dew). It is a direct measure of atmospheric moisture. The higher the dew point, the more humid the air feels.
Dew Point, Humidity, and Comfort
Relative humidity is the percentage of moisture in the air compared to the maximum amount the air can hold at that temperature. When air cools to its dew point, it can no longer hold all its moisture, resulting in condensation. Dew point is a more absolute measure of moisture than relative humidity and is often used to describe comfort levels:
- Dew point below 10°C (50°F): Dry and comfortable
- Dew point 10–16°C (50–60°F): Comfortable
- Dew point 16–18°C (60–65°F): Becoming humid
- Dew point 18–21°C (65–70°F): Humid and uncomfortable
- Dew point above 21°C (70°F): Very humid, oppressive
Why is Dew Point Important?
Knowing the dew point helps in weather forecasting, HVAC design, agriculture, and understanding personal comfort. It is also crucial for preventing condensation and mold growth indoors.