Zhuge Liang can predict the weather. Why didn't he calculate that it would rain in the upstream valley?

First of all, The Battle of Shanggu is from Luo Guanzhong's novel Romance of the Three Kingdoms, which is also fictional! Perhaps this is the perfect ending written by Mr. Luo Guanzhong for Prime Minister Zhuge!

In 234 AD, Zhuge Liang led the troops stationed in Qishan, and Sima Yi deployed in Weishui area! In this way, the prelude to the "Battle of Shanggu" was opened. Zhuge Liangyun not only raised the curtain, but also personally went to survey the terrain and plan the battle plan. He went to the south of Weihe River and found that the terrain here was special. I have a brilliant idea. This place is called Fangshang Valley.

Shanggu is located between two mountains, with low terrain and narrow entrance. Only one person and one horse can pass at a time. There is a flat land in the east of the valley, which can accommodate some people. The valley above is like a gourd, and it is also an excellent terrain for ambush and annihilation. The Prime Minister ordered people to bury dry wood, sulfur, gunpowder and other inflammable and explosive articles in the valley, and thousands of elite soldiers were hidden in the mountains on both sides. Everything is ready, just waiting for the fish to bite.

Zhuge Liang also ordered Wei Yan to challenge Sima Yi, only to lose but not to win. According to his plan, Sima Yi and others were introduced into the valley bit by bit. When Sima Yi's army entered the valley above, they only heard a call. Soldiers on the mountain threw countless pieces of wood and stones to block the entrance to the valley. He dropped the torch he had prepared in advance, and then the fire burst into flames. The valley above is full of smoke, and below is a sea of fire. Everything is waiting for Sima Yi and his son to become a barbecue.

Sima Yi cried with her two sons in her arms: "Our father and son are going to die here." Suddenly, the wind and cloud suddenly appeared, with dark clouds and heavy rain. The rain doused the raging fire, and Sima Yi smiled: "Heaven won't kill me. If I don't kill it now, when will it be? " In this way, their father and son rushed out of the encirclement! All this was seen by the Prime Minister standing on the mountain. As soon as the Prime Minister closed his eyes, he sighed, "Man proposes, God disposes."

The scientific explanation is that the entrance to the upper valley is narrow, the inside is wide, the sides are high and the middle is low, which is not conducive to air circulation. Once a fire breaks out in the valley. When the temperature rises rapidly, the air near the ground will expand and rise when heated. These upper and surrounding cold air contract and sink. Convective valley wind is formed, so there will be sudden changes in the situation. Then the bottom of the valley is too hot, the hot air flow also rises to a certain height, and the water vapor in the air condenses into clouds because of the temperature drop. In addition, a large number of smoke tickets generated by the burning of these dry firewood rose into the sky, providing an ideal condensation nucleus for water vapor condensation and accelerating water vapor condensation. The small water droplets in these clouds collide with each other and get bigger, which eventually leads to a downpour. So Sima and his son were able to escape.

In fact, this is just a sentence from a novelist. There is no such battle in history. Mr. Luo Guanzhong's writing "God helps Cao but not Han" is also a kind of personal subjective color!