In the real atmosphere, highs and lows have rarely the same strength and thus equal wind flow pattern around them. Thus the advection of warm or cold air is rarely equal.[2] Furthermore, their shape and position are rarely as perfect as in the illustration quadrants either.[2] There are thus three types of saddles or cols: the symmetrical, the cyclonic and anticyclonic.
- Symmetric
In the symmetrical saddle area, cyclonic and anticyclonic flows are in balance. This type is the least prevalent, since usually one of these two influences prevails.[5]
- Anticyclonic
In the anticyclonic col, the curvature of the high pressure area isobars is greater than that of the cyclonic flow. The influence of the adjoining high-pressure areas dominates so the formation of a strong front here is unlikely. The weather is very calm and is mainly determined by the air mass properties. In warm mass, especially in the winter and during summer nights, fog and stratus form. It is usually sunny during daytime in summer but cumulus clouds may persist in colder mass.[5]
- Cyclonic
In the cyclonic col, the curvature of the cyclonic isobars is greater than that of the anticyclonic flow. As a result, the adjacent low-pressure areas dominate and the properties are comparable with a trough. The resulting convergent air movement causes frontal clouds and precipitation in humid air. In case of unstable air, strong thunderstorms often occur during the summer.[5]
