Collect 4 proverbs about the weather and explain them.

"Clouds are hanging in the sky, and rain is dripping on the ground": Hook clouds are called hook cirrus clouds in meteorology, which generally appear in front of warm fronts and low pressure, indicating that front or low pressure is coming, which is a harbinger of rain. But after rain or winter, there will be sunny days or frost one after another; Hook clouds dissipate, sunny days are drier ","winter hook clouds, sun dust "proverb.

"The clouds go east and the wind blows; Clouds go west and wear hemp fiber ":The clouds here refer to the low clouds in the low-pressure area. The low pressure is from west to east (in fact, it often moves from southwest to northeast). The cloud goes west, indicating that this place is in front of the low pressure, because it will rain locally; The cloud is moving eastward, indicating that the low pressure has moved past the local area, and the local area is behind the low pressure. The weather is going to clear up, and a strong wind often blows before it clears up.

"Dark clouds cover the morning, and the wind will come even if it doesn't rain": It means that there are dark clouds covering the sun in the southeast in the morning, which indicates rain. Because the warm and humid southeast wind blows in the morning, the temperature is higher than the local air, which causes the upper part to be cold and the lower part to be hot, and the water vapor easily rises into clouds. In addition, during the day, the ground is heated, and the air convection rises, which further promotes the clouds to rise. When it meets cold water vapor, it becomes water droplets, which may make it windless and rainy.

Wearing a hat on the mountain means that the air pressure is low, and most of the water vapor in the air forms clouds at the top of the mountain. As for whether it will rain, it generally depends. If the clouds gradually decrease and thicken, there is a great possibility of rain. On the contrary, if the clouds gradually rise and thin, the possibility of rain is small.