How is the hail formed? What is the reason?

Hail is formed when small ice crystals collide with supercooled water droplets during falling, because the temperature drops sharply.

Hail usually occurs when cold and warm air meet violently from February to May in Gregorian calendar, and it may also land in a strong and persistent thunderstorm in midsummer. Every year, all parts of China are hit by different degrees of hail. Especially in the mountainous and hilly areas in the north, the eastern part of the Qinghai-Tibet Plateau and the Yunnan-Guizhou area, the terrain is complex, the weather is changeable and there are many hail, which is very harmful to agriculture.

Heavy hail destroyed crops and houses, injured people and killed livestock. Extraordinary hail is bigger than grapefruit, which will kill people, destroy a large area of farmland and trees, and destroy buildings and vehicles. It has powerful lethality. Hail disaster is one of the serious natural disasters in China.

Hazards of hail:

Hail disaster is a serious meteorological disaster caused by strong convective weather system. Although it appears in a small range and in a short time, it is fierce and strong, and is often accompanied by other weather processes such as strong winds and heavy rains. China is a country with frequent hail disasters. Hail brings huge losses to agriculture, construction, communication, electricity, transportation and people's lives and property every year.

Hail is a disastrous weather that harms agricultural production in spring and summer. When hail occurs, it is often accompanied by strong winds, severe cooling and strong lightning. A hail attack, light yield reduction, heavy refusal to harvest.