Do you know how tornadoes are formed?

This is a tornado caused by the vertical wind shear of the typhoon front (ultra-low altitude). Wind shear is a sudden change of wind speed and direction. More than an hour before the tornado, the surface wind speed near the Pearl River Estuary was generally around 30km/h (about 8m/s, 4-5 winds), while at the same time, at the height of 850hPa (about 1500m), the wind speed quickly increased to 102km/h (about 28 m/h). Such strong wind shear will produce strong cyclonic convergence and upward movement, which provides a hotbed for the occurrence of tornadoes. At the same time, the trumpet-shaped terrain of the Pearl River Estuary also provides favorable conditions for the occurrence of tornadoes. When the southeast wind from the east of the typhoon flows into the horn, the airflow is blocked by the surrounding mountains, which is easy to produce a small vortex. Just like pouring water into a bag, the water will swirl around the wall of the bag. When these local vortices meet the cyclone convergence zone caused by wind shear, they will accelerate their rotation and form tornadoes. This also makes the Pearl River Estuary one of the tornado-prone areas in history. The cause of strong low-altitude vertical wind shear After the typhoon landed on the ocean, the wind speed near the typhoon surface dropped rapidly due to the friction of the mainland and the loss of the cold core which developed rapidly in ocean heating, but the wind speed over the typhoon did not drop so fast. So there is strong wind shear. This wind shear includes low-altitude wind shear and ultra-low-altitude wind shear. It is for this reason that most tornadoes brought by typhoons are located within 200 kilometers from the coastline, because typhoons can still maintain strong wind shear shortly after landing.