What are the characteristics of airflow and weather in saddle pressure area?

There are compression axis and tension axis: along the compression axis, the airflow converges to the center of saddle-shaped air pressure zone; Along the stretching axis, the airflow diverges from the center of the saddle-shaped air pressure area to both sides. When the angle between the frontal impact and the tensile axis is less than 45 degrees, it is beneficial to frontogenesis, and if there is enough water vapor in the warm air mass climbing along the frontal impact, it is easy to cause precipitation; When the angle between the frontal impact and the tensile axis is greater than 45 degrees, it is beneficial to frontal elimination. Generally, the wind speed in saddle pressure area is relatively small. When the atmospheric stratification is stable and there is warm and humid air flow from the ground to the saddle-shaped air pressure area, the water vapor near the ground condenses at night due to the radiation cooling of the ground, which is easy to form radiation fog.