Rapid City, South Dakota air pressure map

The importance of atmospheric pressure

Atmospheric pressure is one of the most important meteorological elements. The change in pressure in space and time is closely related to the development of the main atmospheric processes: the inhomogeneity of the pressure field in space is the direct cause of the occurrence of air currents, and pressure fluctuations in time are the main cause of changes in the weather in a particular area. The higher the atmospheric pressure, the more likely the weather will be dry and sunny.

On the other hand, when we have a system with a lower pressure, this means that the air mass is less dense. This is because the air is more humid or hotter. Thus, ambient air flows inward towards the center of the system, while light air flows upward. When light, warm air rises and meets colder layers, it condenses into clouds with precipitation.

In systems where the pressure is very low, storms are formed. These clouds are about to form and move across the sky. For these clouds to form, hot, humid air must rise high enough to cause vertical development.