What phenomenon indicates that it is going to rain?
First, ants can move.
"Ants move the snake aisle, and the heavy rain will come soon." This is a classic proverb in the countryside. Just as literally, when you see ants moving in droves, you know it's going to rain. Because ants are creatures that nest underground, their long-term living habits make them very sensitive to the change of air humidity. Generally, ants can know whether it has rained recently by the change of humidity in the air. When the air humidity increases before it rains, ants will feel dangerous in low-lying places and move their nests from low-lying places to high-lying places. In another case, snakes are not in the cave in broad daylight, but running around, which may also mean that it will rain heavily soon.
Second, swallows and dragonflies fly very low.
In addition, when it is going to rain, there will be a lot of mosquitoes and they will bite people everywhere. The reason is that before it rains, the weather is sultry, the air pressure is usually very low, and the humidity in the air will be heavier. A large number of mosquitoes and small flying insects will start flying at low altitude. Swallows and dragonflies can fly very low to prey on these small flying insects, which can also be used as a sign of rain.
Third, fish swim on the water.
When it's going to rain, the clouds in the sky are thick and the air pressure is very low, and people will feel a little depressed. Fish usually breathe oxygen dissolved in water. When the air pressure is low, the dissolved oxygen will be less, and the fish will feel bored, so they usually choose to swim to the surface to breathe.
Fourth, frogs croak.
Frog's skin and organs are very sensitive to weather changes. Whenever stormy weather comes, they will pair up in groups and make a scene. Especially before the thunderstorm weather comes in summer, frogs gather more and more, and their calls become louder and denser.
Five, the earthworm out of the hole
Before it rains, the ground is wet and soft, and earthworms will crawl out of the ground, which is also a sign of rain.
Sixth, the weather changes.
The air humidity becomes higher, the air pressure decreases, the sky becomes dark, and the sky will be gloomy, sometimes accompanied by thunder and lightning.
Several conditions in the countryside also indicate that it will rain soon. For example, chickens stay overnight and ducks crow happily. The explanation is that chickens and ducks usually enter the cage automatically at night, but if they don't want to enter the cage at night and are still screaming everywhere, it means that it will rain heavily soon.