Why does the sun shine in frosty weather?

The frosty weather conditions are sunny and breezy nights, and the sun will naturally shine when it is sunny.

Clear skies at night are conducive to the rapid radiation cooling of the ground or ground objects. Breeze can fully cool radiation in the thick gas layer, and can also replace the air close to the ground to ensure sufficient water vapor condensation. When there is no wind, there is not much water vapor condensation. When the wind speed is too high, the turbulence is too strong, which makes the air close to the ground strongly mix with the warmer air in the upper layer, which leads to the slow cooling of the air close to the ground, which is not conducive to the formation of dew and frost.

Extended data

About the weather phenomenon of frost:

First, it used to be sunny in first frost and sunny in first frost for a long time.

This proverb embodies such a little meteorological knowledge. If there is frost in one morning, the sunny days will not last long. If there is frost in three mornings, the sunny days will last longer.

When the surface temperature of the object is lower than 0 degrees, the water vapor precipitated at this time will condense into ice crystals on the object and form frost. The appearance of frost means that the local night weather is cold and sunny, and the ground radiation cooling is relatively strong.

As the saying goes, the literal meaning of "Once first frost is sunny" is also very simple. This is a forecast of the future weather trend, which means that if the first frost phenomenon appears on a certain night, the sunny weather will not last long, and there may be rain and snow behind it.

This shows that there are many strong cold air forces controlling this area, and the temperature is too low, unstable and easy to remove, so only one day of frost can be formed.

The second half of the sentence says "there were frosty days in three dynasties and sunny days for a long time", which means that if there is frost in the morning for three consecutive days, or the time is longer, it means that the sunny weather will continue for some time.

If there is frost for several nights in a row, it means that the cold and high pressure are strong, wide, slow and stable, and generally last for several days or even a week. This is the meaning of the three dynasties.

Second, it will be sunny in first frost, and the frost will hit the red sun.

There is also a folk proverb, "It's sunny in first frost, red in first frost and sunny", which should be heard by many people. It means that if there is frost at night, the next day will be sunny and the sun will be bigger.

This can also be explained from meteorology, and we also know that this is scientific and the accuracy is quite high. Because the appearance of frost shows that the local weather is sunny and cold at night, it is often sunny and hot the next day.

The frost here mostly refers to radiation cream. This kind of frost is generally controlled by cold and high pressure from the north. The local area is in a high pressure area, and there is a lot of downward flow, so there is no cloud in Wan Li at night, and the weather is still fine the next day.

And the heavier the frost, the stronger the effective radiation, the better the weather, or the stronger the cold air, of course, the better the weather. Therefore, whether there is frost at night can also predict the weather of the next day, and the accuracy is quite high.