What happens when air reaches its dew point?

When air reaches its dew point, it begins to condense because the temperature has dropped to the point where the air can no longer hold all of the moisture it contains in vapor form. As air cools, it loses its capacity to hold moisture; thus, when it reaches this specific temperature, the excess moisture begins to transition from gas to liquid. This process is responsible for the formation of dew, fog, clouds, and precipitation.

The dew point is a critical concept in understanding weather patterns and atmospheric conditions because it indicates the point at which humidity leads to condensation. A higher dew point usually correlates with more humid conditions, leading to various weather phenomena.