Final answer:
Daily maximum relative humidity refers to the highest level of humidity reached during the day, with relative humidity measuring the amount of water vapor in air relative to the maximum it can hold at a given temperature.
Step-by-step explanation:
When discussing daily maximum relative humidity, we are referring to the highest value of relative humidity reached within a 24-hour period. Relative humidity is a measure of how much water vapor is present in the air compared to the maximum amount of water vapor that the air can hold at a certain temperature. When the air reaches its maximum holding capacity, the relative humidity is 100%. This condition is known as saturation.
Temperature plays a critical role as warm air can contain more water vapor than cold air. For instance, as temperatures fall in the evening, the relative humidity often rises, eventually reaching the dew point, wherein the relative humidity is 100%, and fog can form. Additionally, the concept of relative humidity is important for everyday tasks such as drying hair. Hot air is more effective for drying since it can hold more water vapor and increase the rate of evaporation.
In contexts where the vapor density remains constant, and the temperature rises, the relative humidity will decrease because the air can hold more moisture at higher temperatures. For example, if the relative humidity is high on a cool morning, it will generally decrease as the day becomes warmer, assuming the amount of water vapor in the air stays the same.