The first signs of an approaching warm front include a general movement of air from southwest to northeast, a drop in air pressure, and warmer air found behind the movement of the front. Warm fronts tend to signal a general change in weather.
As a warm front approaches and makes its way through, dew point and air pressure steadily rise. Precipitation tends to occur in the form of rain, sleet and snow. Visibility is often poor. After a warm front passes through, conditions tend to reverse as temperatures rise and precipitation decreases. Warm fronts provide a better understanding of how pressure systems interact with geography to influence weather.