What does the farmer's proverb "Wear a hat on a mountain with rain, and no waist on a mountain without rain" mean? Is there a scientific explanation?

Meaning: If clouds appear on the top of the mountain, it will rain. If clouds appear on the mountainside, it means there will be no rain.

Scientific explanation: When the rain is about to come, because the clouds are dark and low, they often press on the top of the mountains to form a "mountain hat", so it is a precursor to the coming rain. Low clouds such as local stratus clouds are mostly formed due to nighttime radiation cooling. Low clouds such as stratus clouds on the mountainside are likely to be fog. Therefore, clouds reaching the waist of a mountain are generally a symbol of good weather.

Extended information:

Farmer proverbs similar to "A mountain with rain wears a hat, a mountain without rain has no waist":

1. The east wind is strong, so prepare a bamboo hat. The wind is strong and the clouds are rising. The more violent the wind is, the more it will rain.

The meaning of these sentences is: The east wind does not necessarily make it rain. When the east wind is strong, it is terrible. Since the east wind is very small, then. This kind of airflow must come from a very nearby place, perhaps it is a local airflow, and all its properties must be consistent with the local environment.

So it is rare for the weather to get bad. However, if the east wind is very strong, it means that the east wind in the front of the cyclone is air flow from a distance, and there will be a discontinuous surface of the air flow - a front to move locally, so The weather is going to change.

2. The northeast wind brings heavy rain.

The northeasterly wind is an air flow that originates from the northern ocean, or originates from the northern ocean and sweeps across the long-distance ocean surface. It naturally does not contain as much water vapor as the southeasterly wind; however, because it is cold The lower part of the airflow contacts the hotter ocean or land surface in the south, causing it to become colder at the top and warmer at the bottom, causing convection. As a result, the water vapor on the ground is carried to high altitudes, causing clouds and rain.

3. The east wind blows in spring and the rain gurgling.

Meaning: The east wind blows in spring, which is a precursor to bad weather. This is because, on the one hand, the ground warms strongly in spring; on the other hand, the warm air gradually becomes active, the air pressure on the continent gradually decreases, and the anticyclone moves eastward into the sea. Easterly winds will appear at the tail of the anticyclone. These easterly winds will flow to the warmer land, causing the phenomenon of warm below and cold above. At this time, the air layer is unstable and upward convection is prone to occur, so precipitation is very likely to occur.