What do you mean it's raining on the ground?

This is a weather proverb. Not a runway cloud, but a battery cloud;

2. Battery cloud refers to fort-shaped altocumulus cloud or fort-shaped stratocumulus cloud, which mostly appears in front of the trough of low pressure, indicating that the air is unstable. Generally, there are thunderstorms in 8~ 10 hours.

There are many related proverbs. For example, there are clouds hanging in the sky and rain dripping on the ground; There is a broom cloud in the sky, and it will rain in three or five days; There are clouds like feathers in the sky, and there are storms on the ground; The ponytail cloud blew down the boat.

Hook cloud refers to hook cloud, broom cloud, ponytail cloud and feather cloud refers to cirrus cloud. Hook clouds and cirrus clouds that are systematically classified are often born in front of low-pressure fronts or troughs, and in front of high-altitude airflow over cyclones.

At the front of the warm front, warm and humid air climbs along the front, and the warm and humid air gradually reaches saturation through adiabatic cooling in the rising process, and water vapor condenses into small water droplets to form clouds. At first, the warm and humid air has high humidity and low condensation height, and most of it condenses into low clouds in the low-level air, and then the air gradually rises, and most of the remaining water vapor condenses into medium clouds in the hollow. The air continues to climb to the sky, and the water vapor content in the air is already very low, but because the temperature there is very low, the water vapor in the air is still saturated and condenses into high clouds. At first, it was cirrostratus. Later, because there was too little water vapor, it could not form a complete and thick cloud, but only a thin and translucent cirrus cloud or hook cloud. Because this kind of cloud is formed in the process of warm and humid air climbing along the front, the direction of the cloud is obviously the trend of intrusion from a certain system, and it is not randomly suspended in a certain part of the air.

In front of the trough of low pressure or cyclone area, the convergence airflow in this kind of weather system area is very strong, resulting in a strong convergence zone. In the convergence zone, the updraft is very strong, sometimes enough to lift warm and humid air to a very high height. When it is lifted above the frozen layer, water vapor will freeze into ice crystals and form high clouds. At the same time, due to the strong wind in the upper air, water vapor can be blown far away along the direction of the upper air flow, forming cirrus clouds and hook clouds. Therefore, cirrus clouds and hook clouds can be seen far in front of these cyclones or trough areas. Because they are also formed from one direction to a certain direction, we seem to have a strong sense of system intrusion. Clouds converge at a certain point in the sky, especially on the front of a typhoon. The strong converging airflow in the center of a typhoon (not referring to the eye of the typhoon) can often bring water vapor to a very high height and blow it to a very far place along the airflow above, so experienced seaside fishermen can judge that the typhoon comes from cirrus clouds and make preparations for returning to Hong Kong.

Whether it is warm front, trough front or cyclone front, it indicates that these new weather systems will move and affect the local area. When it moves, it is a common weather phenomenon that it is windy and rainy. Therefore, the weather also indicates a process of getting worse. Hook clouds in the sky, rain on the ground, broom clouds in the sky, rain for three or five days, ponytail clouds and falling off the boat all indicate the weather.

Do all cirrus clouds and hook clouds indicate that the weather is bound to get worse? Actually, it's not like this. Everything should be analyzed in detail, not generalized. For example, the false cirrus degenerates into cirrus in the disappearance stage, which not only does not mean that the weather will get worse, but it means that the weather will get better! The cirrus cloud behind the cold front also has this property. Therefore, seeing such a cloud can be analyzed in combination with the weather conditions at that time, and it will be more confident.