Judging the weather with low pressure trough

The low-pressure trough, also called the high-altitude trough, is the cold air at high altitude, and the ground does not feel the temperature drop when the high-altitude trough passes through the boundary. Under normal circumstances, short-term heavy rainfall and strong convective weather often occur when the high-altitude trough crosses the border from March to June, and even heavy rain or more precipitation occurs in strong days, and the sky is clear after crossing. 1 1- In February of the following year, when the high-altitude trough crosses the border, it will be rainy and snowy, and then the sky will be clear or cloudy! ! ! Meteorologist! ! !