I took my children out to play in a sudden heavy rain, but it didn't rain when I walked dozens of meters away from the rain site. How do you explain the border rain to the children?

The so-called "rain on the cow's back" is the abbreviation of "rain separates the cow's back". People use "summer rain separates the cow's back" to describe that there is rain on one side of the cow's back and it doesn't rain there.

Anyone who has lived in mountainous areas for a long time or frequented mountainous areas knows that the weather in mountainous areas is complex and changeable, and such weather changes often occur. This beam is full of dark clouds, but that beam is sunny. The wind and rain on this slope are fierce, but the weather on that slope is sunny. Therefore, there has always been a saying that "ten miles are different from the sky", and some people even use "rain separates the cow's back" to describe the weather characteristics of mountainous areas that are not far apart, but the weather is quite different.

According to the analysis of meteorologists, "cow back rain" needs two conditions. First, the high altitude of this city is affected by the cold vortex (a rotating cold air vortex) or the edge of the cold vortex; Second, there must be tall and complex terrain or features, so that a small cyclone (counterclockwise rotating air vortex) or a small anticyclone (clockwise rotating air vortex) can be generated when the air flows through. Small cyclone is beneficial to the formation of rainfall and the enhancement of rainfall potential, while small anticyclone can inhibit rainfall. Urban high-rise buildings have sprung up like mushrooms after rain, creating the necessary environmental conditions for the formation of "cow back rain", which is also the main reason why "cow back rain" is becoming more and more obvious in some cities.