The dew point is the temperature at which air cools and water vapor condenses to form dew or frost. In general, the higher the relative humidity, the higher the dew point, and the lower the relative humidity, the lower the dew point. The dew point is determined by the amount of water vapor in the air, and the more water vapor there is, the higher the dew point. The dew point is an important indicator in everyday life, helping you make clothing choices or plan outdoor activities. In general, the smaller the difference between the dew point and the air temperature, the wetter the air, and the larger the difference, the drier the air.