As air temperature cools to dewpoint temperature, relative humiditystays the sameincreasesdecreases

As air temperature cools to dew point temperature, relative humidity increases.

Here's why:

1. Dew point is the temperature at which air becomes saturated (100% relative humidity) and water vapor in the air begins to condense into dew.

2. As the air temperature cools, it can hold less water vapor.

3. If the amount of water vapor in the air stays the same, and the air temperature decreases, the relative humidity increases because the air is closer to being saturated.

4. Therefore, as air temperature cools to the dew point temperature, the relative humidity increases.